The experience of recalled trauma during psychedelic experiences and perceived links to subsequent extended difficulties: A mixed-methods study

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Robinson This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7255362/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 27 Nov, 2025 Read the published version in Scientific Reports → Version 1 posted 14 You are reading this latest preprint version Abstract This mixed-methods study investigated the relationship between recalled childhood trauma during psychedelic experiences and subsequent extended psychological difficulties. While psychedelics can facilitate emotional processing of autobiographical material, a minority experience adverse effects or re-traumatization when trauma resurfaces. Phase 1 surveyed 608 individuals who experienced post-psychedelic difficulties lasting beyond acute effects. Those linking difficulties to early trauma (41.8%) were significantly older, more often female, were more likely to report a prior mental-illness diagnosis, and were more likely to use psychedelics in guided settings compared to those without trauma links. They also reported significantly more emotional difficulties but fewer perceptual difficulties after the experience. Phase 2 involved semi-structured interviews with 18 purposively selected participants. Reflexive thematic analysis identified four themes: direct trauma re-experiencing (39% of participants, including some with no prior memory of events), symbolic/somatic re-embodiment (22%), fragmentation and confusion (50%), and varied post-experience trajectories. Outcomes ranged from predominantly positive integration (50%) to mixed effects (28%) to re-traumatization (22%). The study highlights uncertainty around memory veridicality as a source of ongoing distress for some participants. Findings emphasize the critical need for trauma-informed approaches to psychedelic use, stressing appropriate preparation, supportive settings, and robust integration support to maximize therapeutic potential while preventing re-traumatization. Health sciences/Health care Health sciences/Medical research Biological sciences/Psychology Social science/Psychology Psychedelics trauma adverse life experiences memory PTSD mixed methods re-traumatisation extended difficulties Introduction The usage of psychedelic substances has increased in recent years across varied contexts, including psychedelic-assisted therapy (PAT) 1 , guided retreats, and self-guided contexts 2 , 3 . A substantial body of research demonstrates positive outcomes for the majority of users in both clinical trials and recreational contexts. However, regulatory agencies have urged caution, citing the need for more robust, high-quality evidence before broad therapeutic approval. In the absence of therapeutic support, intense psychedelic experiences may be destabilizing and exacerbate pre-existing insecurities 4 . There is also clear evidence that in a minority of cases, some users experience adverse or even traumatic effects and negative long-term psychological outcomes 5 – 11 . One proposed mechanism of psychedelics is the intensified emotional processing of autobiographical material 12 . Emotional breakthroughs, interpersonal connectedness, and positive personality changes have been reported following traumatic re-experiencing in psychedelic experiences 13 – 16 . One such study found that individuals who recollected adverse life events during ayahuasca ceremonies were more likely to report decreased neuroticism immediately following ceremonies as well as three months later 12 . Even highly distressing experiences may later be reinterpreted as transformative, especially in supportive contexts that encourage narrative reconstruction 16 – 18 . A case study of two participants in a psilocybin trial for anorexia nervosa illustrates this complexity: both experienced initial destabilization after resurfacing traumatic memories, but then subsequently also reported long-term symptom reduction 19 . In some cases, psychedelic sessions appear to facilitate the emergence of previously unknown or repressed memories of early trauma, including multiple instances of sexual abuse. For example, Amy Griffin’s memoir The Tell describes how several episodes of childhood trauma resurfaced during psychedelic therapy 20 . Such instances occur often enough to warrant systematic investigation. According to Evens 21 , among individuals who reported a traumatic psychedelic experience with lasting adverse effects, 38% recalled childhood sexual abuse post-experience, and nearly half of those had no prior memory of the events before the session. A key question for researchers and psychedelic therapists is whether apparent recollections of autobiographical memories within psychedelic experiences divulge veridical information about the past or not 22 . Timmerman et al. discuss a case of apparent childhood abuse following a psilocybin experience that was initially thought by the individual to be veridical, but then, during integration, there was a reinterpretation to explore the symbolic meaning of the apparent memory, rather than whether it ever happened 22 . This points to the possibility that some apparent recollections are not veridical accounts of the past but may be metaphorical images akin to those frequently found in the dreams of PTSD sufferers 12 , 18 . There are potential neurological and psychological mechanisms for why past memories and emotions may be remembered during psychedelic experiences. In terms of neurological mechanisms, classic psychedelics activate 5-HT2A receptors and disrupt the default mode network, which is involved in autobiographical memory, narrative selfhood, and emotional regulation 23 , 24 . This may loosen rigid trauma-related schemas and enable access to suppressed material. Psychedelics may also open reconsolidation windows 25 , wherein destabilized memory traces become labile or modifiable, depending on contextual support 24 , 26 . In terms of emotional mechanisms, shame and guilt may play a role by surfacing during the psychedelic experience and prompting reevaluation of past events. These emotions, when safely processed, can facilitate the dismantling of self-critical narratives often rooted in trauma. For instance, Mathai et al. found that psilocybin use was frequently associated with experiences of shame or guilt about past events, and with a small but significant decrease in trait shame that was maintained 2–3 months after use; however 30% showed sustained increases in trait shame 27 . Another study found 7% of participants linked such feelings to resurfaced trauma 8 . For a minority of users, psychedelic use in guided and unguided contexts can induce distressing experiences both during the period of pharmacological effect and after the impact of the drug has worn off 28 . Such extended difficulties, which can last for months or years, can include anxiety, intrusive thoughts, hypervigilance, cognitive confusion, derealization, and depersonalization 5 – 9 , 11 , 29 . Self-report studies have found that some experientially link extended difficulties to re-experiencing past adverse events during the acute psychedelic experience 8 . Similarly, a recent qualitative study based on practitioners who work to support individuals after psychedelic experiences also found that reactivations of childhood trauma were a key source of extended difficulties for some of their clients 30 . Dissociation is a risk following an abrupt experience of apparent memories of past trauma during psychedelic episodes 31 . Reports of fragmentation, depersonalization, and derealization 5 , 29 align with trauma-related dissociation 32 . Thal et al. found that trauma history–not just drug use–was the stronger predictor of dissociation, suggesting psychedelics may interact with underlying vulnerabilities rather than cause dissociation outright 33 . These extended difficulties may occur when resurfaced material is not adequately supported and contained 5 , 8 . Hence, a related challenge is how best to support individuals struggling with trauma-related distress after psychedelic experiences. Practitioners emphasize trauma-informed integration, including therapy, grounding techniques, and meaning-making tools 30 . Both qualitative and quantitative studies highlight the central role of informal resources in recovery from post-psychedelic difficulties. A qualitative study based on user reports emphasized peer support, self-education, meditation, time in nature, and embodied strategies such as exercise and breathing techniques, with participants noting the importance of feeling accepted and validated by others 34 . Another self-report study found that effective coping strategies included self-education, meditation, exposure to nature, and peer and family support 10 . Narrative processing is widely recognized as central to trauma recovery 35 , and in psychedelic contexts, this process may be aided or hindered by how individuals make sense of emotionally intense material. In sum, personalized integration approaches that combine both clinical and informal resources are likely to be optimal. Aims and Research Questions As outlined above, existing research shows that experiences of resurfaced trauma during a psychedelic episode can bring therapeutic breakthroughs or, conversely, lead to disintegration and emotional destabilization 32 . Given the complexity and variety of outcomes, further research is needed on this topic to understand the conditions under which re-experiencing adverse events can lead to an improvement or decline in emotional well-being. This is particularly important considering the widespread hope that psychedelic medicine may represent a breakthrough intervention for PTSD. While prior research has examined challenging psychedelic experiences, few studies have addressed how the experience of resurfaced childhood trauma relates to long-term difficulties. Fewer still have explored how individuals understand and cope with such experiences. This study uses a two-phase mixed-methods design combining a large-scale survey and in-depth interviews with individuals who reported resurfaced childhood trauma during psychedelic use that contributed to lasting psychological challenges. The research questions that guided this inquiry were: (1) How do people experience and understand childhood trauma that emerges during psychedelic sessions, and what characterizes these encounters across memory, body awareness, emotional intensity, and post-session meaning-making? (2) What interpretive, relational, or contextual factors appear to shape whether individuals go on to experience therapeutic integration, ongoing distress, or re-traumatization following such experiences? Together, these questions aim to illuminate both the phenomenological contours of trauma resurfacing and the broader psychosocial processes that influence post-experience trajectories of change. Method Mixed-methods design The study employed a sequential QUAN-QUAL mixed-methods design 36 , consisting of two phases. Phase 1 was an online survey. After completing the first phase, individuals were purposively sampled from the Phase 1 sample based on reporting in the survey that early trauma was linked to their experience of post-psychedelic difficulties. Online in-depth interviews were then conducted with these individuals in Phase 2. Participants Survey Participants were required to have experienced difficulties after the use of a psychedelic in the past that led to functional difficulties that lasted for more than a day after the effects of the drug had concluded. They were also required to be aged 18 or over, and to write English to a proficient or fluent standard. The survey was distributed via an online newsletter, social media channels, student email lists, and a newspaper advertisement. There were no financial incentives for participation. 608 individuals completed the survey. A breakdown of demographic information is available in the Supplementary Material. Interviews : Participants were recruited for interviews if they met the following criteria: (1) They had responded "yes" to the question: "Was there a traumatic experience in your childhood or youth which you think may have played a role in the difficulties that arose during or after the psychedelic experience?"), (2) Classic psychedelics had initiated the difficulties they reported, (3) they were living in a country where English is the primary language, and (4) if they had consented to be approached for a follow-up interview. 33 individuals met these criteria and consented to interviewed. Of these, we were able to arrange and successfully complete interviews with 18 individuals. Of the final sample, 12 were female and 6 were male. The age range was from the early 20s to the late 50s, with a mean of approximately 35. Reported traumas comprised childhood abuses (sexual, physical, and emotional neglect), attachment/relational/abandonment trauma, combat-related, bereavement-related, or illness-related trauma. Psychedelic substances that elicited the difficulties were ayahuasca (6), psilocybin (10), and LSD (2). In terms of the setting of taking the psychedelic, 9 were in facilitator-guided settings, and 9 were in unguided/informal settings. All participants provided informed consent, and confidentiality was assured; participants could review transcripts and withdraw at any time. Procedure and data collection Ethical approval from the University of Greenwich Ethics Board was obtained prior to the commencement of data collection (application ref: 21.5.7.20). Additionally, Bar Ilan University's IRB approved the second phase of the study. All procedures involving human participants were performed in accordance with relevant guidelines and regulations, including the Declaration of Helsinki. All participants provided informed consent prior to participation; interviewees additionally consented to audio-recording and anonymized transcription. No identifying images or other identifying information are included in this article. Survey : Data was collected anonymously via an online survey created in the survey platform Qualtrics, between November 2022 and April 2023. In the questionnaire, after demographic questions, participants were asked to select a particular psychedelic experience for reflection as the focus of the questionnaire, using the following instructions: “Please reflect on one specific psychedelic experience that led to difficulties or challenges lasting beyond the trip itself. If you have had multiple psychedelic experiences that have led to post-trip difficulties, please refer to the one that stands out as most difficult for you to integrate/navigate afterwards.” The measures and assessments included in the current study are shown below. For a complete list of online survey questions, see Supplementary Materials. Interviews Each participant completed a semi-structured interview, lasting 60–90 minutes, with a trained qualitative researcher via a secure video call. The participant shared a narrative of the challenging trip, including the setting and substances used, detailed phenomenological descriptions of what they saw and felt (especially when trauma material arose), how they coped during the event, and how they processed the experience afterward. Open-ended prompts encouraged depth (e.g., “Can you describe what it was like when that memory came up?”; “How did this experience affect you afterward?”). The complete interview guide is available in the Supplementary Materials. Interviewers employed empathetic listening and, when needed, grounding techniques, pausing the interview if a participant became extremely distressed. After each interview, participants were debriefed and provided with resources or referrals for integration support, as appropriate. All interviews were audio-recorded with permission, professionally transcribed verbatim, and anonymized. Transcripts preserved participants’ original wording and emotional tone (with minor filler words removed) to ensure fidelity to their voice while protecting identities. Survey Measures Demographic questions: Age “What is your age?” Answer categories: 18–24, 25–34, 35–44, 45–55, Over 55, Prefer not to answer. Gender : “How do you describe your gender?” Answer categories: Male, Female, Other, Prefer not to say. Education : “What’s your highest level of education?” Answer categories: High school/secondary school, Bachelor’s Degree, Master’s Degree, PhD or above, Other, prefer not to say. Challengingness of the acute experience : “How challenging was the psychedelic experience itself?”, with a 4-point Likert scale response: Not at all challenging, Moderately challenging, Very challenging, Extremely challenging. Dose “Did you or someone else present know the dose you were taking?” Yes/No Setting of experience : “Where did this psychedelic experience happen?” 9 Answer options grouped into two higher-order categories of unguided and guided: Unguided = With a friend, partner, or group of friends / On my own / At a rave, nightclub, or festival / At a party / Other. Guided = In a group ceremony / On a psychedelic retreat / At a psychedelic therapy session / At a clinic or medical trial. Difficulties after the experience “Which of the following options best describes the difficulties/challenges you experienced after your psychedelic trip. Please select all that apply to you.” The following options were presented Emotional difficulties (e.g., the way you felt emotionally or the ability you had to emotionally regulate) Self-perception difficulties (e.g., the way you felt about or understood yourself) Cognitive difficulties (e.g., the way you thought about things) Social difficulties (e.g., the way you interacted the related to other people) Ontological difficulties (e.g., the way you understood reality and existence) Spiritual difficulties (e.g., your spiritual beliefs) Perceptual difficulties (e.g., the way your vision or hearing functioned) Other Difficulties Range of difficulties This was calculated as the number of difficulty types selected in response to the above question. Duration of difficulties : “How long did the difficulties/challenges last after the trip?” Answer categories: Less than a week / Up to a week / More than a week, up to a month / 1–3 months / 3–6 months / 6 months to a year / 1–3 years / Over 3 years Continued use of psychedelics “Do you still take psychedelic drugs?” Yes / No Prior diagnosis “Had you been diagnosed with a mental illness prior to the psychedelic experience?” Yes / No Traumatic experience perceived as linked to difficulties “Was there a traumatic experience in your childhood or youth which you think may have played a role in the difficulties that arose during or after the psychedelic experience?” Yes / No / Unsure Belief in benefits of psychedelics relative to risk : Please rate your agreement with the below statement: “I believe that the insights and healings gained from psychedelics, when taken in a supportive setting, are worth the risks involved.” 4-point Likert scale of Strongly Disagree, Disagree, Agree, Strongly Agree Quantitative Analyses IBM SPSS v.28 was used to run all statistical tests. The analyses compared 19 dependent variables across two independent groups: those who responded Yes or No to the “ Traumatic experience perceived as linked to difficulties” question. For dependent variables measured on a Likert scale or a continuous interval-level scale, t-tests were conducted. For variables measured on a non-interval scale, the Mann-Whitney test was conducted. For variables with categorical response options, Chi-Square analyses were performed. Given the number of tests conducted, the P- value was corrected to p < 0.01 for significance using the Hochberg step-up method 37 . Parametric assumptions were met for the t-test analyses. Qualitative Analysis Transcripts were analyzed using reflexive thematic analysis 38 , combined with specific elements of Multiple Case Narrative methodology 39 . Elements of MCN were incorporated by treating each participant as a distinct case, preserving narrative coherence during within-case analysis before identifying cross-case themes. This allowed us to retain individual meaning structures while systematically comparing experiences across the dataset. This dual analytic approach allowed us to identify case patterns while honoring each person's unique story. A shared codebook was maintained and iteratively refined through discussion among four analysts. Data immersion was achieved through repeated readings of transcripts. Next, coding was conducted using MAXQDA software. Coding of each transcript was done line-by-line, assigning codes for both explicit content (e.g., "flashback," "body froze") and underlying processes (e.g., "regressed to child-self," "ego dissolution"). Discrepancies in coding were resolved through consensus in analyst meetings, ensuring that the codes remained grounded in participants' words and meanings. We then developed themes by clustering related codes and examining conceptual connections across cases. The results below present participant quotes, along with their ID numbers (P1–P18); minor verbal fillers have been removed for readability. To enhance trustworthiness, we employed researcher triangulation, maintained reflexive journals documenting analytical decisions, and conducted member checking with select participants to verify interpretations. Our reporting adheres to the Consolidated Criteria for Reporting Qualitative Research (COREQ) guidelines for comprehensive qualitative research reporting 40 . Results Quantitative results In terms of responses to the question “Was there a traumatic experience in your childhood or youth which you think may have played a role in the difficulties that arose during or after the psychedelic experience?”, 243 (41.8%) responded Yes , 180 (31.0%) responded No , and 158 (27.2%) responded Unsure. For the quantitative between-groups analysis, those who responded Unsure were excluded to ensure a clear comparison of those with and without the experience of trauma linked to their post-psychedelic difficulties. Table 1 presents the inferential and descriptive statistics from comparing 18 variables across the Yes and No groups, using a series of t-tests, Mann-Whitney tests, and Chi-square tests, depending on the nature of the dependent variable. Table 1 Between-groups analyses of selected variables for the Yes and No response groups for "Was there a traumatic experience in your childhood or youth which you think may have played a role in the difficulties that arose during or after the psychedelic experience?" Variable Test performed Test statistic df p value Descriptive statistic for "yes" group Descriptive statistic for "no" group Education level Mann-Whitney U = 16966.000 N.A. 0.758 Mean: 2.57 Mean: 2.60 Duration of difficulties Mann-Whitney U = 21051.500 N.A. 0.574 Mean: 4.83 Mean: 4.73 Age Mann-Whitney U = 18621.500 N.A. 0.007 Mean: 3.08 Mean: 2.74 Gender Chi Square Χ = 13.54 1 0.001 57.7% female 39.2% female Knowledge of dose Chi Square Χ = 1.348 1 0.246 77.7 yes 72.8 yes Guided vs unguided setting Chi Square Χ = 10.168 1 0.001 63.7 unguided setting 78.5 unguided setting Diagnosed with mental illness prior to experience? Chi Square Χ = 20.648 1 0.001 73.8% yes 50.2% yes Do you still take psychedelic drugs? Chi Square Χ = 4.38 1 0.039 61.4% yes 51.2% yes Social Difficulty Chi Square Χ = 4.97 1 0.163 57.6% experienced 46.7% experienced Perceptual Difficulty Chi Square Χ = 10.52 1 0.001 18.5% experienced 32.2% experienced Cognitive Difficulty Chi Square Χ = 1.03 1 0.322 52.3% experienced 57.2% experienced Emotional Difficulty Chi Square Χ = 10.46 1 0.001 81.9% experienced 68.3% experienced Spiritual Difficulty Chi Square Χ = 0.02 1 0.923 35.0% experienced 35.6% experienced Ontological Difficulty Chi Square Χ = 4.04 1 0.028 45.7% experienced 55.6% experienced Self-Related Difficulty Chi Square Χ = 4.21 1 0.026 63.8% experienced 53.9% experienced Other Difficulty Chi Square 0.53 1 0.271 19.3% experienced 22.2% experienced Challengingness of the psychedelic experience t-test t = 1.059 363 0.145 Mean: 3.15 Mean: 3.04 Range of difficulties t-test t = 0.131 421 0.448 Mean: 3.74 Mean: 3.72 Belief that psychedelics are worth the risk t-test t = 3.748 273 0.001 Mean: 3.62 Mean: 3.32 Note: significant p values are highlighted in grey for ease of visual reference. Displayed percentages for ‘Guided vs unguided setting’ represent the proportion in unguided settings. The results in Table 1 show that those who experienced a link between an early trauma and their experience of post-psychedelic difficulties, when compared with those who did not, were on average (1) significantly older, (2) had a significantly higher proportion of females, (3) were significantly more likely to be diagnosed with a mental illness prior to the psychedelic experience, (4) were more likely to be taking psychedelics in a guided setting, and (5) be more likely to believe that using psychedelics lead to benefits that outweigh the risk involved. In terms of the post-psychedelic extended difficulties they reported, there were (6) significantly more likely to report emotional difficulties after the psychedelic experience, but (7) significantly less likely to report perceptual difficulties. [INSERT Table 1 HERE] Qualitative Results Despite the heterogeneity of participants’ backgrounds and psychedelic experiences, clear patterns emerged in how trauma was encountered during the psychedelic state. All participants described their past trauma coming to conscious awareness during the difficult trip, though the mode of resurfacing varied. Seven participants (~ 39%) described vividly re-living a traumatic event, often with intense sensory and emotional detail. Of these, three participants explicitly stated that the trauma they re-experienced had not been previously recalled in conscious memory prior to the psychedelic session. Four others did not retrieve an explicit autobiographical memory but instead encountered trauma-related content through symbolic imagery, intense emotion, or somatic sensations they interpreted as related to earlier adverse experiences. The experiences of 9 participants were often disjointed or confusing, with fragments of memory or feelings that were hard to piece together. Below, we present the four major themes that encapsulate these variations: (1) resurfacing and re-experiencing of childhood trauma, (2) symbolic or somatic re-embodiment of trauma, (3) fragmentation and confusion, and (4) post-experience outcomes from therapeutic integration to re-traumatization. These themes, with their prevalence, key characteristics, and representative quotes, are summarized in Table 2 . We illustrate each theme with representative interview examples (using participant numbers for attribution). Table 2 Qualitative themes, prevalence, characteristics and quotes Theme Prevalence Key Characteristics Representative Quotes 1. resurfacing and re-experiencing of apparent childhood trauma 7/18 participants (~ 39%) • Seeing scenes from past trauma • Feeling of reliving the trauma • High emotional intensity • Recovery of suppressed memories • Amplification of known trauma "The ayahuasca, just the entire trip, was like, yeah… your father sexually abused you. It was just like 100%. It put my entire life in context […] Every single thing made sense after that." (P5) "The image was there, and the knowing was just there." (P4) "I felt like I'd become that child again. I'm about to be punished." (P2) 2. symbolic or somatic re-embodiment of trauma 4/18 participants (~ 22%) • Intense bodily sensations • Strong emotional reactions • Symbolic imagery • Non-literal representation of trauma • Physical manifestations "It really kind of replicated that trauma experience of like shit goes very bad, very sideways. I barely survived it, and now I'm back." (P1) "I felt like I was being pulled down these rabbit holes –fast. I would come upon a scene, and then I'd be pulled backwards out again and down the next one." (P10) 3.Fragmentation and confusion ~ 9/18 participants (~ 50%) • Chaotic emergence of trauma content • Difficulty making sense of experience • Uncertainty about memory authenticity • Disorientation during and after • Nonlinear trauma processing "I can't trust it. I don't know if that was real… The challenging thing is, like, that's a horrible thing to not know if it's real or not." (P3) "The next day, I continued to have these weird muscle spasms... my legs started clamping, doing this involuntarily." (P15) 4. post-experience change from therapeutic integration to re-traumatization All participants Positive change (~ 8–9/18): • Healing • Personal growth • Resolution of trauma • Life improvements Negative change (~ 4–5/18): • Increased trauma symptoms • Destabilization • Re-traumatization Mixed change (~ 4–5/18): • Both benefits and harms Positive: "I'm a much better person because of it." (P9) Negative: "I didn't cope well after it… I had a lot of problems with sleep, and I was having flashbacks." (P7) Mixed: "Overall, it was a very healing experience. But… not having closure about it was harmful for me and my family." (P3) [INSERT Table 2 ] Trauma-related psychedelic experiences and associated post-experience trajectories Our analysis also elicited distinct patterns in how childhood trauma surfaces during challenging psychedelic experiences. Despite the diverse backgrounds and substances used by participants, four primary themes emerged: (1) resurfacing and re-experiencing of childhood trauma, (2) symbolic or somatic re-embodiment of trauma, (3) fragmentation and confusion, and (4) post-experience outcomes from therapeutic integration to re-traumatization. Approximately 39% of participants (7/18) reported directly re-experiencing childhood trauma during their psychedelic session, often with vivid sensory recall. As one participant (P5) described: "The ayahuasca, just the entire trip, was like, yeah... your father sexually abused you. It was just like 100%. It put my entire life in context [...] Every single thing made sense after that." Another subset of participants (22%) experienced trauma through bodily sensations or symbolic imagery rather than explicit memories, with one participant (P1) noting: "It really kind of replicated that trauma experience of like shit goes very bad, very sideways. I barely survived it, and now I'm back." Half of the participants (50%) described fragmentation and confusion during their experience, struggling to make sense of emerging trauma content or questioning the authenticity of recovered memories. One participant (P3) expressed this uncertainty: "I can't trust it. I don't know if that was real... The challenging thing is, like, that's a horrible thing to not know if it's real or not." As shown in Table 3 , participants' post-experience trajectories of change fell into three categories: predominantly positive integration (50%), mixed negative/positive change (28%), and predominantly negative or re-traumatization (22%). Those reporting positive trajectories often described profound healing despite initial distress: "I'm probably a much better person because of it" (P9). Those with mixed trajectories acknowledged benefits alongside ongoing challenges: "Overall, it was a very healing experience. But... not having closure about it was harmful for me and my family" (P3). Participants reporting negative trajectories described symptoms resembling re-traumatization: "I didn't cope well after it. I had a lot of problems with sleep, and I was having flashbacks" (P7). Table 3 Trajectories of Trauma-Related Psychedelic Experiences as Described in Interviews Trajectory of Change Definition Participants Example Participant Reflections Predominantly Positive Integration Despite the difficulty, the experience led to healing insights or improvements. Participants processed the resurfaced trauma and reported reduced trauma symptoms, personal growth, or positive life changes (e.g. seeking therapy, improved relationships). They often reframed the experience as a meaningful turning point. ~ 9 (50%) – e.g. P1, P4, P9, P10, P11, P17, P18, etc. “It was very healing, although it nearly killed me.” (P4 ” I’m much happier, and my capacity for joy is much greater.” (P1) “I’m probably a much better person because of it.” (P9) Mixed Trajectory The experience had both beneficial and adverse aspects. Participants gained some insight or partial healing, but also experienced ongoing challenges (e.g. difficulty integrating certain elements, new anxieties). They might value some lessons from the experience but remain ambivalent or cautious. ~ 5(28%) – e.g. P3, P6, P13, P15, P17. “But yeah, so, overall, it was a very healing experience. But then... Having a door open and then not being able to have closure about it was harmful for me and my family.” (P3) Predominantly Negative / Re-traumatization The experience was mainly harmful. It either reinforced the original trauma or added new trauma. Participants reported exacerbated symptoms (e.g. more frequent flashbacks, panic, insomnia) or emotional downturns lasting long after the session. They did not perceive a net benefit and often regretted or were traumatized by the psychedelic experience itself. ~ 4(22%) – e.g. P2, P5, P7, P16. “I was feeling really overwhelmed… I worried that even shutting my eyes would take me back there.” (P2). “I didn’t cope well after it. I had a lot of problems with sleep, and I was having flashbacks.” (P7) “I just went into like a dark night of the soul for literally a year.” (P5) [INSERT Table 3 ] Discussion The quantitative survey findings provided evidence that individuals who report a link between an early trauma and post-psychedelic extended difficulties, when compared with those who do not, are on average older, more likely to be diagnosed with a mental illness prior to the psychedelic experience, more likely to be taking psychedelics in a guided setting, more likely to believe that using psychedelics lead to benefits that outweigh the risk involved, and have a higher proportion of female. In terms of the age difference between the groups, one possible interpretation is that older participants may be more likely to reflect on earlier life experiences in the context of psychedelic difficulties. While the survey did not ask whether these traumatic events had been previously repressed or forgotten, this pattern may still align with developmental theories such as Hollis’s idea of midlife as a period when unconscious material becomes more salient or emotionally charged 41 . However, further research is needed to determine whether age-related recall dynamics played a role in how trauma was interpreted in these experiences. We also found that participants who linked their post-psychedelic difficulties to early trauma were more likely to be in guided settings for the psychedelic experience. This can be interpreted as those with past trauma having a stronger motivation for safety and containment in their psychedelic work, and possibly an explicit intention to work on post-traumatic symptoms in a guided setting rather than to take the drug recreationally 42 . Another interpretation in the opposite causal direction is that guided settings may create a therapeutic environment (therapeutic suggestibility) where repressed material, such as early trauma, is more likely to emerge (or be perceived to emerge) during the psychedelic experience. The higher proportion of females in the group linking trauma to difficulties could align with previous research that suggests women are more likely to experience early interpersonal trauma (e.g., sexual abuse) and to engage in help-seeking behaviors 43 . It may also reflect gendered differences in emotional expressivity and trauma disclosure in post-experience narratives 44 , and possible serotonergic sensitivity due to hormonal factors 45 , 46 . Goldner et al. also found that women were more likely to engage in "tend-and-befriend" coping rather than avoidance, which may reflect gendered differences in disclosure and help-seeking, and might partially explain the therapeutic-seeking and openness to guided use 47 . A belief in the benefits of psychedelics is higher in the group with recalled trauma. This may stem from having had an experience in healing through catharsis or self-transformation, despite encountering difficulties. It could also reflect a form of post-traumatic growth, where participants retrospectively frame challenging experiences as meaningful or valuable, even when they involve resurfacing trauma 14 . In terms of the post-psychedelic extended difficulties reported, those who re-experienced past trauma were significantly more likely to report emotional difficulties after the psychedelic experience than those who did not, but were less likely to report perceptual difficulties. This may also point to suggest different neural processing - possibly, this pattern might reflect differential engagement of affective vs. sensory systems; however, the present data cannot adjudicate mechanisms. 32 , 48 , 32 Discussion of qualitative findings The qualitative analysis supports previous findings that psychedelic experiences have the potential to heal or exacerbate trauma 22 , 26 . On the one hand, participants described how they facilitated emotional and somatic breakthroughs, as has been previously described in research 49 . On the other side, some participants conveyed that they led to emotional overwhelm and re-traumatization, where the set and setting were problematic and where there was little support for integration and navigating subsequent challenges. The themes elicited from the qualitative data capture various experiential features of the perceived link between early trauma and post-psychedelic extended difficulties. Theme 1, reported by 39% of participants, captured the experience of remembering past childhood trauma during the psychedelic experience and the direct emotional implications of this. Participants described how the psychedelic experience revealed what appeared to be repressed traumatic memories (of which some had no prior memory). They discussed how this brought profound emotional challenges and opportunities. This echoes the quantitative finding that emotional difficulties after the psychedelic episode were more frequent in the group reporting past trauma. The immediate aftermath for one participant (P5) included "a dark night of the soul for literally a year," demonstrating the potentially destabilizing nature of such revelations. Whether such experiences were a veridical recollection of past events was uncertain, particularly given that a proportion of participants had no prior memory of the event, and this uncertainty was itself anxiety-inducing for some. For example, P3's case shows this feature of being haunted by uncertainty. This represents prior work on this topic, which mentions that the lack of certainty - "not knowing if it's real or not" - can become traumatic, leading to ongoing distress long after the session 22 . Theme 2, symbolic/sensory re-embodiment of trauma (experienced by 22% of participants) captures the bodily, symbolic, and non-literal representation of trauma, which the participants interpreted as meaningfully linking to past adverse events. These physical manifestations can be interpreted as indirect representations of repressed or suppressed emotions that seek expression 50 . The therapeutic value of such experiences may lie in their ability to allow emotional processing without explicit recall of traumatic events 12 . These experiences underscore psychedelics' capacity to engage trauma on a non-verbal level - effectively allowing a person to work through trauma feelings and responses without re-experiencing the original event. However, their indirect nature requires careful professional post-session support and integration to help facilitate healing. Theme 3: fragmentation and confusion were experienced by 50% of our participants. It represents reports of how the psychedelic state can sometimes overwhelm an ability to cope, leading to a feeling of disintegration that may itself echo the feeling of being traumatized. For example, P15's experience suggests that even when participants know something important was processed through intense physical release, the nonverbal and strange nature of the experience can make it difficult to explain or integrate. Such cases may require extensive reflection or therapy afterward to construct meaning from the experience. Theme 4 captured the varied post-experience trajectories from therapeutic integration to re-traumatization. The divergent trajectories reported (as summarized in Table 2 ) suggest that preparation, context, and support play crucial roles in determining whether psychedelic encounters with trauma lead to healing or further harm. These outcomes may also be shaped by factors such as attachment history, cultural framing, and the degree of interpersonal or therapeutic support available during or after the experience 51 . Generally, participants with positive outcomes (50%) had been prepared within a therapeutic framework or sought integration afterward, while those with adverse outcomes (22%) often lacked sufficient support. The meaning ascribed to the experience also appears critical. Even when the trip was extremely challenging, those who found meaning (like P9, who decided the experience revealed his calling to help others) tended to fare better than those who viewed it as "just bad" or meaningless suffering. The findings suggest that challenging psychedelic experiences involving the reactivation or recollection of past trauma need to minimize harms and maximize potential benefits. With appropriate preparation, setting, and follow-up integration, they can serve as opportunities for deep healing, providing exposure therapy or catharsis that frees people from past trauma 12 . Without adequate support, such experiences risk re-traumatization 21 , 26 . Participants who experienced trips alone without any guide or subsequent therapy show how a lack of support can leave someone to cope with the fallout on their own, potentially worsening trauma symptoms. Conversely, those who actively engaged in integration work through psychotherapy, journaling, meditation, support groups, or deep personal reflection are more likely to report that they transform their challenging experiences into healing. Limitations and Future Directions Several notable limitations accompany this study. First, while the survey phase had a large dataset, the self-reported nature of past experiences and trauma experiences may lead to recall bias, social desirability bias, or underreporting, especially given the sensitive topic. Online administration further limits control over participant understanding and engagement. The qualitative phase allowed for richer exploration of trauma’s impacts but included only a small, non-random subset of the survey sample who were purposively sampled for reporting a link between childhood trauma and extended post-psychedelic difficulties. This targeted sampling may have introduced selection bias, as those who volunteered for interviews may have differed systematically from those who did not, who met the same criteria, for example, being more comfortable discussing trauma or having fewer extreme experiences. As such, the findings from interviews may not be representative of the broader population surveyed. Moreover, conducting interviews online can limit rapport and nonverbal communication, both of which are crucial in sensitive discussions. Theme prevalences reported for the 18 interviews are descriptive of this purposively sampled subset. They should not be generalized to the Phase 1 cohort or wider populations. Finally, both phases rely on internet access and digital literacy, which may potentially exclude marginalized populations and introduce sample bias. Overall, while the mixed-methods design enriches the understanding of trauma, these methodological limitations must be carefully addressed. Future research in this area will benefit from longitudinal studies with existing cohorts, such as the Dunedin study 52 . This would allow for objective information about adverse childhood experiences that were gathered at the time to be cross-checked against reports of such experiences from those working with psychedelics. Another important step will be to gain the views of experts and practitioners working in the field of psychedelic integration to collate their knowledge of best practice when working with individuals processing perceived recollections of, or emotions associated with, past trauma. The study focused on people who believed an earlier experience of trauma led to post-psychedelic difficulties. It did not ask how many of these earlier experiences of trauma were recalled for the first time during the psychedelic experience. Nor did it focus directly on the question: ‘How sure are you that this earlier experience of trauma really happened?’ Although some interviewees voluntarily shared their feelings on the topic, expressing a range of views from very certain to not-so-certain. We did not seek external corroboration of recalled events; findings concern subjective recall and meaning-making rather than verification of historical accuracy. The degree of certainty regarding the truth of the memory may be related to the degree of catharsis experienced by the person, although this requires further exploration in future studies. Certainty is not the same as truth - there remains the question of whether or how often recovered memories of early trauma during psychedelic experiences are genuine and veridical, when they are hallucinations, how a person (and their therapist) can discriminate between genuine memory and hallucination, and how to live with the possibility of not knowing for sure. There is also the question, worthy of future investigation, of whether memories of early trauma could be suggested to or implanted in individuals while they are in suggestible psychedelic states, by guides or therapists overly invested in the ‘trauma catharsis’ theory of psychedelic healing or more broadly the ‘trauma culture’. In summary, this study points towards the central importance of developing a trauma-informed and trauma-literate approach to working with psychedelics that can be applied across clinical and non-clinical settings. The benefits of this will be threefold. Firstly, it will allow for evidence-based support for the therapeutic and existential challenges that emerge for individuals who are re-experiencing or processing what appear to be memories of past trauma. Secondly, this will provide a foundation of support for those with PTSD, such as army veterans, who seek therapeutic help through psychedelics 12 . Thirdly, a trauma-informed approach to psychedelic work will help to mitigate against the chance that the psychedelic experience itself is traumatic 26 . Our qualitative findings suggest that the trajectories of change following the experience are influenced by the context and care surrounding it. A trauma-informed psychedelic culture will maximize the conditions for integration and support, so that encounters with past events (or what may be subjectively construed as such) can be transformed into a step toward wholeness rather than a re-wounding. Declarations Acknowledgements The authors are deeply grateful to all the individuals who participated in this study. We thank the survey respondents for sharing their experiences and insights, and especially the interview participants who courageously recounted complex and often painful journeys. Their openness and honesty made this research possible. We also acknowledge the Challenging Psychedelic Experiences Project (CPEP) for its foundational support and the broader psychedelic research community for its ongoing commitment to safety, integrity, and inquiry. Author Contributions GS: Conceptualization; Methodology; Formal Analysis; Investigation; Writing – Original Draft; Writing - Review & Editing; Visualization; Project Administration. NT: Data Curation; Investigation. MS: Writing – Review & Editing. JE: Conceptualization; Investigation; Writing – Review & Editing. Project Administration. OR: Supervision; Conceptualization; Investigation; Methodology; Formal Analysis; Writing - Review & Editing. Funding This research was conducted as part of the Challenging Psychedelic Experiences Project (CPEP), a broader initiative supported by the William G. Nash Foundation and the Sarlo Family. However, this specific study did not receive any direct funding from these or other sources. The funders had no role in the design, data collection, analysis, interpretation, or writing of this manuscript. Competing Interests The authors declare no competing interests. Data Availability The datasets generated and/or analyzed during the current study are not publicly available due to the sensitive nature of trauma-related narratives and the need to protect participant confidentiality. De-identified excerpts or summary data may be available from the corresponding author upon reasonable request and pending ethical approval. References Mitchell, J. M. & Anderson, B. T. Psychedelic therapies reconsidered: compounds, clinical indications, and cautious optimism. Neuropsychopharmacol. 49 , 96–103 (2024). Basedow, L. A. & Kuitunen‐Paul, S. Motives for the use of serotonergic psychedelics: A systematic review. Drug and Alcohol Review 41 , 1391–1403 (2022). Kopra, E. I. et al. 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REBUS and the Anarchic Brain: Toward a Unified Model of the Brain Action of Psychedelics. Pharmacological Reviews 71 , 316–344 (2019). Kéri, S. Trauma and Remembering: From Neuronal Circuits to Molecules. Life 12 , 1707 (2022). Nader, K. & Hardt, O. A single standard for memory: the case for reconsolidation. Nat Rev Neurosci 10 , 224–234 (2009). Calder, A. E., Diehl, V. J. & Hasler, G. Traumatic Psychedelic Experiences. in Current Topics in Behavioral Neurosciences (Springer, Berlin, Heidelberg, 2025). doi:10.1007/7854_2025_579. Mathai, D. S. et al. Shame, Guilt and Psychedelic Experience: Results from a Prospective, Longitudinal Survey of Real-World Psilocybin Use. Journal of Psychoactive Drugs 1–12 (2025) doi:10.1080/02791072.2025.2461997. Wood, M. J., McAlpine, R. G. & Kamboj, S. K. Strategies for resolving challenging psychedelic experiences: insights from a mixed-methods study. Sci Rep 14 , 28817 (2024). Argyri, E. K. et al. Navigating Groundlessness: An interview study on dealing with ontological shock and existential distress following psychedelic experiences. PLoS One e0322501 (2025) doi:https://doi.org/10.1371/journal.pone.0322501. Argyri, E. K. et al. Practitioner perspectives on extended difficulties and optimal support strategies following psychedelic experiences: A qualitative analysis. Preprint at Research Square https://doi.org/10.21203/rs.3.rs-6303856/v1 (2025). Nijenhuis, E., Van Der Hart, O. & Steele, K. Trauma-related Structural Dissociation of the Personality. Act Nerv Super 52 , 1–23 (2010). Elfrink, S. & Bergin, L. Psychedelic iatrogenic structural dissociation: an exploratory hypothesis on dissociative risks in psychedelic use. Front. Psychol. 16 , 1528253 (2025). Thal, S. B., Daniels, J. K. & Jungaberle, H. The link between childhood trauma and dissociation in frequent users of classic psychedelics and dissociatives. J. Subst. Use 24 , 524–531 (2019). Robinson, O. C. et al. Coming back together: a qualitative survey study of coping and support strategies used by people to cope with extended difficulties after the use of psychedelic drugs. Front. Psychol. 15 , 1369715 (2024). Kaminer, D. Healing Processes in Trauma Narratives: A Review. South African Journal of Psychology 36 , 481–499 (2006). Creswell, J. W. & Plano Clark, V. L. Designing and Conducting Mixed Methods Research . (Sage, Thousand Oaks, 2017). Hochberg, Y. A sharper Bonferroni procedure for multiple tests of significance. Biometrika 75 , 800–802 (1988). Braun, V. & Clarke, V. Using thematic analysis in psychology. Qualitative Research in Psychology 3 , 77–101 (2006). Shkedi, A. Multiple Case Narrative: A Qualitative Approach to Studying Multiple Populations . (John Benjamins Publishing Company, Amsterdam, 2005). Tong, A., Sainsbury, P. & Craig, J. Consolidated criteria for reporting qualitative research (COREQ): a 32-item checklist for interviews and focus groups. International Journal for Quality in Health Care 19 , 349–357 (2007). Hollis, J. The Middle Passage: From Misery to Meaning in Midlife . (Inner City Books, Toronto, 1993). Litt, L., Cohen, L. R. & Hien, D. Seeking Safety: A present-focused integrated treatment for PTSD and substance use disorders. in Posttraumatic stress and substance use disorders: a comprehensive clinical handbook 183–207 (Routledge, New York, NY, 2019). Kessler, R. C. et al. Trauma and PTSD in the WHO World Mental Health Surveys. European Journal of Psychotraumatology 8 , (2017). Olff, M., Langeland, W., Draijer, N. & Gersons, B. P. R. Gender differences in posttraumatic stress disorder. Psychological Bulletin 133 , 183–204 (2007). Suazo, N. C., Reyes, M. E., Contractor, A. A., Thomas, E. D. & Weiss, N. H. 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K., Dupuis, D., Timmermann, C. & Granqvist, P. Psychedelics, attachment, and enculturation dynamics: Prospects and challenges. Journal of Psychedelic Studies (2025) doi:10.1556/2054.2025.00459. The Dunedin Study - Dunedin Multidisciplinary Health & Development Research Unit. https://dunedinstudy.otago.ac.nz/ (2025). Additional Declarations No competing interests reported. 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A substantial body of research demonstrates positive outcomes for the majority of users in both clinical trials and recreational contexts. However, regulatory agencies have urged caution, citing the need for more robust, high-quality evidence before broad therapeutic approval. In the absence of therapeutic support, intense psychedelic experiences may be destabilizing and exacerbate pre-existing insecurities\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e. There is also clear evidence that in a minority of cases, some users experience adverse or even traumatic effects and negative long-term psychological outcomes\u003csup\u003e\u003cspan additionalcitationids=\"CR6 CR7 CR8 CR9 CR10\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e–\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eOne proposed mechanism of psychedelics is the intensified emotional processing of autobiographical material\u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/sup\u003e. Emotional breakthroughs, interpersonal connectedness, and positive personality changes have been reported following traumatic re-experiencing in psychedelic experiences\u003csup\u003e\u003cspan additionalcitationids=\"CR14 CR15\" citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e–\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e. One such study found that individuals who recollected adverse life events during ayahuasca ceremonies were more likely to report decreased neuroticism immediately following ceremonies as well as three months later\u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/sup\u003e. Even highly distressing experiences may later be reinterpreted as transformative, especially in supportive contexts that encourage narrative reconstruction\u003csup\u003e\u003cspan additionalcitationids=\"CR17\" citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e–\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u003c/sup\u003e. A case study of two participants in a psilocybin trial for anorexia nervosa illustrates this complexity: both experienced initial destabilization after resurfacing traumatic memories, but then subsequently also reported long-term symptom reduction\u003csup\u003e\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eIn some cases, psychedelic sessions appear to facilitate the emergence of previously unknown or repressed memories of early trauma, including multiple instances of sexual abuse. For example, Amy Griffin’s memoir \u003cem\u003eThe Tell\u003c/em\u003e describes how several episodes of childhood trauma resurfaced during psychedelic therapy\u003csup\u003e\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e\u003c/sup\u003e. Such instances occur often enough to warrant systematic investigation. According to Evens\u003csup\u003e\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u003c/sup\u003e, among individuals who reported a traumatic psychedelic experience with lasting adverse effects, 38% recalled childhood sexual abuse post-experience, and nearly half of those had no prior memory of the events before the session.\u003c/p\u003e\u003cp\u003eA key question for researchers and psychedelic therapists is whether apparent recollections of autobiographical memories within psychedelic experiences divulge veridical information about the past or not\u003csup\u003e\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u003c/sup\u003e. Timmerman et al. discuss a case of apparent childhood abuse following a psilocybin experience that was initially thought by the individual to be veridical, but then, during integration, there was a reinterpretation to explore the symbolic meaning of the apparent memory, rather than whether it ever happened\u003csup\u003e\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u003c/sup\u003e. This points to the possibility that some apparent recollections are not veridical accounts of the past but may be metaphorical images akin to those frequently found in the dreams of PTSD sufferers\u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e,\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eThere are potential neurological and psychological mechanisms for why past memories and emotions may be remembered during psychedelic experiences. In terms of neurological mechanisms, classic psychedelics activate 5-HT2A receptors and disrupt the default mode network, which is involved in autobiographical memory, narrative selfhood, and emotional regulation\u003csup\u003e\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e,\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e\u003c/sup\u003e. This may loosen rigid trauma-related schemas and enable access to suppressed material. Psychedelics may also open reconsolidation windows\u003csup\u003e\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u003c/sup\u003e, wherein destabilized memory traces become labile or modifiable, depending on contextual support\u003csup\u003e\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e,\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e\u003c/sup\u003e. In terms of emotional mechanisms, shame and guilt may play a role by surfacing during the psychedelic experience and prompting reevaluation of past events. These emotions, when safely processed, can facilitate the dismantling of self-critical narratives often rooted in trauma. For instance, Mathai et al. found that psilocybin use was frequently associated with experiences of shame or guilt about past events, and with a small but significant decrease in trait shame that was maintained 2–3 months after use; however 30% showed sustained increases in trait shame\u003csup\u003e\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e\u003c/sup\u003e. Another study found 7% of participants linked such feelings to resurfaced trauma\u003csup\u003e\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eFor a minority of users, psychedelic use in guided and unguided contexts can induce distressing experiences both during the period of pharmacological effect and after the impact of the drug has worn off\u003csup\u003e\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e\u003c/sup\u003e. Such extended difficulties, which can last for months or years, can include anxiety, intrusive thoughts, hypervigilance, cognitive confusion, derealization, and depersonalization\u003csup\u003e\u003cspan additionalcitationids=\"CR6 CR7 CR8\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e–\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e,\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e,\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e\u003c/sup\u003e. Self-report studies have found that some experientially link extended difficulties to re-experiencing past adverse events during the acute psychedelic experience\u003csup\u003e\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e. Similarly, a recent qualitative study based on practitioners who work to support individuals after psychedelic experiences also found that reactivations of childhood trauma were a key source of extended difficulties for some of their clients\u003csup\u003e\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eDissociation is a risk following an abrupt experience of apparent memories of past trauma during psychedelic episodes\u003csup\u003e\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e\u003c/sup\u003e. Reports of fragmentation, depersonalization, and derealization\u003csup\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e,\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e\u003c/sup\u003e align with trauma-related dissociation\u003csup\u003e\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e\u003c/sup\u003e. Thal et al. found that trauma history–not just drug use–was the stronger predictor of dissociation, suggesting psychedelics may interact with underlying vulnerabilities rather than cause dissociation outright\u003csup\u003e\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eThese extended difficulties may occur when resurfaced material is not adequately supported and contained\u003csup\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e,\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e. Hence, a related challenge is how best to support individuals struggling with trauma-related distress after psychedelic experiences. Practitioners emphasize trauma-informed integration, including therapy, grounding techniques, and meaning-making tools\u003csup\u003e\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e\u003c/sup\u003e. Both qualitative and quantitative studies highlight the central role of informal resources in recovery from post-psychedelic difficulties. A qualitative study based on user reports emphasized peer support, self-education, meditation, time in nature, and embodied strategies such as exercise and breathing techniques, with participants noting the importance of feeling accepted and validated by others\u003csup\u003e\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e\u003c/sup\u003e. Another self-report study found that effective coping strategies included self-education, meditation, exposure to nature, and peer and family support\u003csup\u003e\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u003c/sup\u003e. Narrative processing is widely recognized as central to trauma recovery\u003csup\u003e\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e\u003c/sup\u003e, and in psychedelic contexts, this process may be aided or hindered by how individuals make sense of emotionally intense material. In sum, personalized integration approaches that combine both clinical and informal resources are likely to be optimal.\u003c/p\u003e\n\u003ch3\u003eAims and Research Questions\u003c/h3\u003e\n\u003cp\u003eAs outlined above, existing research shows that experiences of resurfaced trauma during a psychedelic episode can bring therapeutic breakthroughs or, conversely, lead to disintegration and emotional destabilization\u003csup\u003e\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e\u003c/sup\u003e. Given the complexity and variety of outcomes, further research is needed on this topic to understand the conditions under which re-experiencing adverse events can lead to an improvement or decline in emotional well-being. This is particularly important considering the widespread hope that psychedelic medicine may represent a breakthrough intervention for PTSD. While prior research has examined challenging psychedelic experiences, few studies have addressed how the experience of resurfaced childhood trauma relates to long-term difficulties. Fewer still have explored how individuals understand and cope with such experiences. This study uses a two-phase mixed-methods design combining a large-scale survey and in-depth interviews with individuals who reported resurfaced childhood trauma during psychedelic use that contributed to lasting psychological challenges. The research questions that guided this inquiry were:\u003c/p\u003e\u003cp\u003e\u003cb\u003e(1)\u003c/b\u003e \u003cem\u003eHow do people experience and understand childhood trauma that emerges during psychedelic sessions, and what characterizes these encounters across memory, body awareness, emotional intensity, and post-session meaning-making?\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003e(2)\u003c/b\u003e \u003cem\u003eWhat interpretive, relational, or contextual factors appear to shape whether individuals go on to experience therapeutic integration, ongoing distress, or re-traumatization following such experiences?\u003c/em\u003e\u003c/p\u003e\u003cp\u003eTogether, these questions aim to illuminate both the phenomenological contours of trauma resurfacing and the broader psychosocial processes that influence post-experience trajectories of change.\u003c/p\u003e"},{"header":"Method","content":"\u003ch2\u003eMixed-methods design\u003c/h2\u003e\u003cp\u003eThe study employed a sequential QUAN-QUAL mixed-methods design\u003csup\u003e\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e\u003c/sup\u003e, consisting of two phases. Phase 1 was an online survey. After completing the first phase, individuals were purposively sampled from the Phase 1 sample based on reporting in the survey that early trauma was linked to their experience of post-psychedelic difficulties. Online in-depth interviews were then conducted with these individuals in Phase 2.\u003c/p\u003e\u003ch3\u003eParticipants\u003c/h3\u003e\u003cp\u003e\u003cstrong\u003eSurvey\u003c/strong\u003e\u003c/p\u003e\u003cp\u003eParticipants were required to have experienced difficulties after the use of a psychedelic in the past that led to functional difficulties that lasted for more than a day after the effects of the drug had concluded. They were also required to be aged 18 or over, and to write English to a proficient or fluent standard. The survey was distributed via an online newsletter, social media channels, student email lists, and a newspaper advertisement. There were no financial incentives for participation. 608 individuals completed the survey. A breakdown of demographic information is available in the Supplementary Material.\u003c/p\u003e\u003cp\u003e\u003cb\u003eInterviews\u003c/b\u003e: Participants were recruited for interviews if they met the following criteria: (1) They had responded \"yes\" to the question: \"Was there a traumatic experience in your childhood or youth which you think may have played a role in the difficulties that arose during or after the psychedelic experience?\"), (2) Classic psychedelics had initiated the difficulties they reported, (3) they were living in a country where English is the primary language, and (4) if they had consented to be approached for a follow-up interview. 33 individuals met these criteria and consented to interviewed. Of these, we were able to arrange and successfully complete interviews with 18 individuals. Of the final sample, 12 were female and 6 were male. The age range was from the early 20s to the late 50s, with a mean of approximately 35. Reported traumas comprised childhood abuses (sexual, physical, and emotional neglect), attachment/relational/abandonment trauma, combat-related, bereavement-related, or illness-related trauma. Psychedelic substances that elicited the difficulties were ayahuasca (6), psilocybin (10), and LSD (2). In terms of the setting of taking the psychedelic, 9 were in facilitator-guided settings, and 9 were in unguided/informal settings. All participants provided informed consent, and confidentiality was assured; participants could review transcripts and withdraw at any time.\u003c/p\u003e\u003ch3\u003eProcedure and data collection\u003c/h3\u003e\u003cp\u003eEthical approval from the University of Greenwich Ethics Board was obtained prior to the commencement of data collection (application ref: 21.5.7.20). Additionally, Bar Ilan University's IRB approved the second phase of the study. All procedures involving human participants were performed in accordance with relevant guidelines and regulations, including the Declaration of Helsinki. All participants provided informed consent prior to participation; interviewees additionally consented to audio-recording and anonymized transcription. No identifying images or other identifying information are included in this article.\u003c/p\u003e\u003cp\u003e\u003cb\u003eSurvey\u003c/b\u003e: Data was collected anonymously via an online survey created in the survey platform Qualtrics, between November 2022 and April 2023. In the questionnaire, after demographic questions, participants were asked to select a particular psychedelic experience for reflection as the focus of the questionnaire, using the following instructions: “Please reflect on one specific psychedelic experience that led to difficulties or challenges lasting beyond the trip itself. If you have had multiple psychedelic experiences that have led to post-trip difficulties, please refer to the one that stands out as most difficult for you to integrate/navigate afterwards.” The measures and assessments included in the current study are shown below. For a complete list of online survey questions, see Supplementary Materials.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eInterviews\u003c/strong\u003e\u003c/p\u003e\u003cp\u003e Each participant completed a semi-structured interview, lasting 60–90 minutes, with a trained qualitative researcher via a secure video call. The participant shared a narrative of the challenging trip, including the setting and substances used, detailed phenomenological descriptions of what they saw and felt (especially when trauma material arose), how they coped during the event, and how they processed the experience afterward. Open-ended prompts encouraged depth (e.g., “Can you describe what it was like when that memory came up?”; “How did this experience affect you afterward?”). The complete interview guide is available in the Supplementary Materials. Interviewers employed empathetic listening and, when needed, grounding techniques, pausing the interview if a participant became extremely distressed. After each interview, participants were debriefed and provided with resources or referrals for integration support, as appropriate. All interviews were audio-recorded with permission, professionally transcribed verbatim, and anonymized. Transcripts preserved participants’ original wording and emotional tone (with minor filler words removed) to ensure fidelity to their voice while protecting identities.\u003c/p\u003e\u003ch3\u003eSurvey Measures\u003c/h3\u003e\u003cp\u003e\u003cem\u003eDemographic questions: Age\u003c/em\u003e “What is your age?” Answer categories: 18–24, 25–34, 35–44, 45–55, Over 55, Prefer not to answer. \u003cem\u003eGender\u003c/em\u003e: “How do you describe your gender?” Answer categories: Male, Female, Other, Prefer not to say. \u003cem\u003eEducation\u003c/em\u003e: “What’s your highest level of education?” Answer categories: High school/secondary school, Bachelor’s Degree, Master’s Degree, PhD or above, Other, prefer not to say.\u003c/p\u003e\u003cp\u003e\u003cem\u003eChallengingness of the acute experience\u003c/em\u003e: “How challenging was the psychedelic experience itself?”, with a 4-point Likert scale response: Not at all challenging, Moderately challenging, Very challenging, Extremely challenging.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eDose\u003c/strong\u003e\u003c/p\u003e\u003cp\u003e“Did you or someone else present know the dose you were taking?” Yes/No\u003c/p\u003e\u003cp\u003e\u003cem\u003eSetting of experience\u003c/em\u003e: “Where did this psychedelic experience happen?” 9 Answer options grouped into two higher-order categories of unguided and guided: \u003cem\u003eUnguided\u003c/em\u003e = With a friend, partner, or group of friends / On my own / At a rave, nightclub, or festival / At a party / Other. \u003cem\u003eGuided\u003c/em\u003e = In a group ceremony / On a psychedelic retreat / At a psychedelic therapy session / At a clinic or medical trial.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eDifficulties after the experience\u003c/strong\u003e\u003c/p\u003e\u003cp\u003e“Which of the following options best describes the difficulties/challenges you experienced after your psychedelic trip. Please select all that apply to you.” The following options were presented\u003c/p\u003e\u003col\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eEmotional difficulties (e.g., the way you felt emotionally or the ability you had to emotionally regulate)\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eSelf-perception difficulties (e.g., the way you felt about or understood yourself)\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eCognitive difficulties (e.g., the way you thought about things)\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eSocial difficulties (e.g., the way you interacted the related to other people)\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eOntological difficulties (e.g., the way you understood reality and existence)\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eSpiritual difficulties (e.g., your spiritual beliefs)\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003ePerceptual difficulties (e.g., the way your vision or hearing functioned)\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eOther Difficulties\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003c/ol\u003e\u003cp\u003e\u003cstrong\u003eRange of difficulties\u003c/strong\u003e\u003c/p\u003e\u003cp\u003eThis was calculated as the number of difficulty types selected in response to the above question.\u003c/p\u003e\u003cp\u003e\u003cem\u003eDuration of difficulties\u003c/em\u003e: “How long did the difficulties/challenges last after the trip?” Answer categories: Less than a week / Up to a week / More than a week, up to a month / 1–3 months / 3–6 months / 6 months to a year / 1–3 years / Over 3 years\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eContinued use of psychedelics\u003c/strong\u003e\u003c/p\u003e\u003cp\u003e“Do you still take psychedelic drugs?” Yes / No\u003c/p\u003e\u003cp\u003e\u003cstrong\u003ePrior diagnosis\u003c/strong\u003e\u003c/p\u003e\u003cp\u003e“Had you been diagnosed with a mental illness prior to the psychedelic experience?” Yes / No\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eTraumatic experience perceived as linked to difficulties\u003c/strong\u003e\u003c/p\u003e\u003cp\u003e“Was there a traumatic experience in your childhood or youth which you think may have played a role in the difficulties that arose during or after the psychedelic experience?” Yes / No / Unsure\u003c/p\u003e\u003cp\u003e\u003cem\u003eBelief in benefits of psychedelics relative to risk\u003c/em\u003e: Please rate your agreement with the below statement: “I believe that the insights and healings gained from psychedelics, when taken in a supportive setting, are worth the risks involved.” 4-point Likert scale of Strongly Disagree, Disagree, Agree, Strongly Agree\u003c/p\u003e\u003ch2\u003eQuantitative Analyses\u003c/h2\u003e\u003cp\u003eIBM SPSS v.28 was used to run all statistical tests. The analyses compared 19 dependent variables across two independent groups: those who responded \u003cem\u003eYes\u003c/em\u003e or \u003cem\u003eNo\u003c/em\u003e to the “\u003cem\u003eTraumatic experience perceived as linked to difficulties” question.\u003c/em\u003e For dependent variables measured on a Likert scale or a continuous interval-level scale, t-tests were conducted. For variables measured on a non-interval scale, the Mann-Whitney test was conducted. For variables with categorical response options, Chi-Square analyses were performed. Given the number of tests conducted, the \u003cem\u003eP-\u003c/em\u003evalue was corrected to \u003cem\u003ep\u003c/em\u003e \u0026lt; 0.01 for significance using the Hochberg step-up method\u003csup\u003e\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e\u003c/sup\u003e. Parametric assumptions were met for the t-test analyses.\u003c/p\u003e\u003ch3\u003eQualitative Analysis\u003c/h3\u003e\u003cp\u003eTranscripts were analyzed using reflexive thematic analysis\u003csup\u003e\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e\u003c/sup\u003e, combined with specific elements of Multiple Case Narrative methodology\u003csup\u003e\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e\u003c/sup\u003e. Elements of MCN were incorporated by treating each participant as a distinct case, preserving narrative coherence during within-case analysis before identifying cross-case themes. This allowed us to retain individual meaning structures while systematically comparing experiences across the dataset. This dual analytic approach allowed us to identify case patterns while honoring each person's unique story. A shared codebook was maintained and iteratively refined through discussion among four analysts. Data immersion was achieved through repeated readings of transcripts. Next, coding was conducted using MAXQDA software. Coding of each transcript was done line-by-line, assigning codes for both explicit content (e.g., \"flashback,\" \"body froze\") and underlying processes (e.g., \"regressed to child-self,\" \"ego dissolution\"). Discrepancies in coding were resolved through consensus in analyst meetings, ensuring that the codes remained grounded in participants' words and meanings. We then developed themes by clustering related codes and examining conceptual connections across cases. The results below present participant quotes, along with their ID numbers (P1–P18); minor verbal fillers have been removed for readability. To enhance trustworthiness, we employed researcher triangulation, maintained reflexive journals documenting analytical decisions, and conducted member checking with select participants to verify interpretations. Our reporting adheres to the Consolidated Criteria for Reporting Qualitative Research (COREQ) guidelines for comprehensive qualitative research reporting\u003csup\u003e\u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\u003ch2\u003eQuantitative results\u003c/h2\u003e\u003cp\u003eIn terms of responses to the question \u0026ldquo;Was there a traumatic experience in your childhood or youth which you think may have played a role in the difficulties that arose during or after the psychedelic experience?\u0026rdquo;, 243 (41.8%) responded \u003cem\u003eYes\u003c/em\u003e, 180 (31.0%) responded \u003cem\u003eNo\u003c/em\u003e, and 158 (27.2%) responded \u003cem\u003eUnsure.\u003c/em\u003e For the quantitative between-groups analysis, those who responded \u003cem\u003eUnsure\u003c/em\u003e were excluded to ensure a clear comparison of those with and without the experience of trauma linked to their post-psychedelic difficulties. Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e presents the inferential and descriptive statistics from comparing 18 variables across the \u003cem\u003eYes\u003c/em\u003e and \u003cem\u003eNo\u003c/em\u003e groups, using a series of t-tests, Mann-Whitney tests, and Chi-square tests, depending on the nature of the dependent variable.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eBetween-groups analyses of selected variables for the \u003cem\u003eYes\u003c/em\u003e and \u003cem\u003eNo\u003c/em\u003e response groups for \"Was there a traumatic experience in your childhood or youth which you think may have played a role in the difficulties that arose during or after the psychedelic experience?\"\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"7\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eVariable\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTest performed\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eTest statistic\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003edf\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003ep\u003c/em\u003e value\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eDescriptive statistic for \"yes\" group\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eDescriptive statistic for \"no\" group\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eEducation level\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMann-Whitney\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003eU\u003c/em\u003e\u0026thinsp;=\u0026thinsp;16966.000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eN.A.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.758\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eMean: 2.57\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003eMean: 2.60\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDuration of difficulties\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMann-Whitney\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003eU\u003c/em\u003e\u0026thinsp;=\u0026thinsp;21051.500\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eN.A.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.574\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eMean: 4.83\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003eMean: 4.73\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMann-Whitney\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003eU\u003c/em\u003e\u0026thinsp;=\u0026thinsp;18621.500\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eN.A.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.007\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eMean: 3.08\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003eMean: 2.74\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGender\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eChi Square\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003eΧ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;13.54\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e57.7% female\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e39.2% female\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eKnowledge of dose\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eChi Square\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003eΧ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;1.348\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.246\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e77.7 yes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e72.8 yes\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGuided vs unguided setting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eChi Square\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003eΧ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;10.168\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e63.7 unguided setting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e78.5 unguided setting\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDiagnosed with mental illness prior to experience?\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eChi Square\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003eΧ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;20.648\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e73.8% yes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e50.2% yes\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDo you still take psychedelic drugs?\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eChi Square\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003eΧ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;4.38\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.039\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e61.4% yes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e51.2% yes\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSocial Difficulty\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eChi Square\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003eΧ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;4.97\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.163\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e57.6% experienced\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e46.7% experienced\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePerceptual Difficulty\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eChi Square\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003eΧ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;10.52\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e18.5% experienced\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e32.2% experienced\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCognitive Difficulty\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eChi Square\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003eΧ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;1.03\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.322\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e52.3% experienced\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e57.2% experienced\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eEmotional Difficulty\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eChi Square\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003eΧ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;10.46\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e81.9% experienced\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e68.3% experienced\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSpiritual Difficulty\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eChi Square\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003eΧ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.02\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.923\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e35.0% experienced\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e35.6% experienced\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eOntological Difficulty\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eChi Square\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003eΧ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;4.04\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.028\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e45.7% experienced\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e55.6% experienced\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSelf-Related Difficulty\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eChi Square\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003eΧ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;4.21\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.026\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e63.8% experienced\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e53.9% experienced\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eOther Difficulty\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eChi Square\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.53\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.271\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e19.3% experienced\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e22.2% experienced\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eChallengingness of the psychedelic experience\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003et-test\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003et\u0026thinsp;=\u0026thinsp;1.059\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e363\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.145\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eMean: 3.15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003eMean: 3.04\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRange of difficulties\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003et-test\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003et\u0026thinsp;=\u0026thinsp;0.131\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e421\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.448\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eMean: 3.74\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003eMean: 3.72\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBelief that psychedelics are worth the risk\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003et-test\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003et\u0026thinsp;=\u0026thinsp;3.748\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e273\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eMean: 3.62\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003eMean: 3.32\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"7\"\u003eNote: significant \u003cem\u003ep\u003c/em\u003e values are highlighted in grey for ease of visual reference.\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"7\"\u003eDisplayed percentages for \u0026lsquo;Guided vs unguided setting\u0026rsquo; represent the proportion in unguided settings.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eThe results in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e show that those who experienced a link between an early trauma and their experience of post-psychedelic difficulties, when compared with those who did not, were on average (1) significantly older, (2) had a significantly higher proportion of females, (3) were significantly more likely to be diagnosed with a mental illness prior to the psychedelic experience, (4) were more likely to be taking psychedelics in a guided setting, and (5) be more likely to believe that using psychedelics lead to benefits that outweigh the risk involved. In terms of the post-psychedelic extended difficulties they reported, there were (6) significantly more likely to report emotional difficulties after the psychedelic experience, but (7) significantly less likely to report perceptual difficulties.\u003c/p\u003e\u003cp\u003e[INSERT Table \u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e HERE]\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\u003ch2\u003eQualitative Results\u003c/h2\u003e\u003cp\u003eDespite the heterogeneity of participants\u0026rsquo; backgrounds and psychedelic experiences, clear patterns emerged in how trauma was encountered during the psychedelic state. All participants described their past trauma coming to conscious awareness during the difficult trip, though the mode of resurfacing varied. Seven participants (~\u0026thinsp;39%) described vividly re-living a traumatic event, often with intense sensory and emotional detail. Of these, three participants explicitly stated that the trauma they re-experienced had not been previously recalled in conscious memory prior to the psychedelic session. Four others did not retrieve an explicit autobiographical memory but instead encountered trauma-related content through symbolic imagery, intense emotion, or somatic sensations they interpreted as related to earlier adverse experiences. The experiences of 9 participants were often disjointed or confusing, with fragments of memory or feelings that were hard to piece together. Below, we present the four major themes that encapsulate these variations: (1) resurfacing and re-experiencing of childhood trauma, (2) symbolic or somatic re-embodiment of trauma, (3) fragmentation and confusion, and (4) post-experience outcomes from therapeutic integration to re-traumatization. These themes, with their prevalence, key characteristics, and representative quotes, are summarized in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. We illustrate each theme with representative interview examples (using participant numbers for attribution).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eQualitative themes, prevalence, characteristics and quotes\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"4\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTheme\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePrevalence\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eKey Characteristics\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eRepresentative Quotes\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003e1. resurfacing and re-experiencing of apparent childhood trauma\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e7/18 participants (~\u0026thinsp;39%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u0026bull; Seeing scenes from past trauma \u0026bull; Feeling of reliving the trauma \u0026bull; High emotional intensity \u0026bull; Recovery of suppressed memories \u0026bull; Amplification of known trauma\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\"The ayahuasca, just the entire trip, was like, yeah\u0026hellip; your father sexually abused you. It was just like 100%. It put my entire life in context [\u0026hellip;] Every single thing made sense after that.\" (P5) \"The image was there, and the knowing was just there.\" (P4) \"I felt like I'd become that child again. I'm about to be punished.\" (P2)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003e2. symbolic or somatic re-embodiment of trauma\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e4/18 participants (~\u0026thinsp;22%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u0026bull; Intense bodily sensations \u0026bull; Strong emotional reactions \u0026bull; Symbolic imagery \u0026bull; Non-literal representation of trauma \u0026bull; Physical manifestations\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\"It really kind of replicated that trauma experience of like shit goes very bad, very sideways. I barely survived it, and now I'm back.\" (P1) \"I felt like I was being pulled down these rabbit holes \u0026ndash;fast. I would come upon a scene, and then I'd be pulled backwards out again and down the next one.\" (P10)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003e3.Fragmentation and confusion\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e~\u0026thinsp;9/18 participants (~\u0026thinsp;50%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u0026bull; Chaotic emergence of trauma content \u0026bull; Difficulty making sense of experience \u0026bull; Uncertainty about memory authenticity \u0026bull; Disorientation during and after \u0026bull; Nonlinear trauma processing\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\"I can't trust it. I don't know if that was real\u0026hellip; The challenging thing is, like, that's a horrible thing to not know if it's real or not.\" (P3) \"The next day, I continued to have these weird muscle spasms... my legs started clamping, doing this involuntarily.\" (P15)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003e4. post-experience change from therapeutic integration to re-traumatization\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAll participants\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003ePositive change (~\u0026thinsp;8\u0026ndash;9/18): \u0026bull; Healing \u0026bull; Personal growth \u0026bull; Resolution of trauma \u0026bull; Life improvements Negative change (~\u0026thinsp;4\u0026ndash;5/18): \u0026bull; Increased trauma symptoms \u0026bull; Destabilization \u0026bull; Re-traumatization Mixed change (~\u0026thinsp;4\u0026ndash;5/18): \u0026bull; Both benefits and harms\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003ePositive: \"I'm a much better person because of it.\" (P9) Negative: \"I didn't cope well after it\u0026hellip; I had a lot of problems with sleep, and I was having flashbacks.\" (P7) Mixed: \"Overall, it was a very healing experience. But\u0026hellip; not having closure about it was harmful for me and my family.\" (P3)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e\u003ch2\u003e[INSERT Table \u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e]\u003c/h2\u003e\u003cdiv id=\"Sec14\" class=\"Section3\"\u003e\u003ch2\u003eTrauma-related psychedelic experiences and associated post-experience trajectories\u003c/h2\u003e\u003cp\u003eOur analysis also elicited distinct patterns in how childhood trauma surfaces during challenging psychedelic experiences. Despite the diverse backgrounds and substances used by participants, four primary themes emerged: (1) resurfacing and re-experiencing of childhood trauma, (2) symbolic or somatic re-embodiment of trauma, (3) fragmentation and confusion, and (4) post-experience outcomes from therapeutic integration to re-traumatization. Approximately 39% of participants (7/18) reported directly re-experiencing childhood trauma during their psychedelic session, often with vivid sensory recall. As one participant (P5) described: \u003cem\u003e\"The ayahuasca, just the entire trip, was like, yeah... your father sexually abused you. It was just like 100%. It put my entire life in context [...] Every single thing made sense after that.\"\u003c/em\u003e Another subset of participants (22%) experienced trauma through bodily sensations or symbolic imagery rather than explicit memories, with one participant (P1) noting: \u003cem\u003e\"It really kind of replicated that trauma experience of like shit goes very bad, very sideways. I barely survived it, and now I'm back.\"\u003c/em\u003e\u003c/p\u003e\u003cp\u003eHalf of the participants (50%) described fragmentation and confusion during their experience, struggling to make sense of emerging trauma content or questioning the authenticity of recovered memories. One participant (P3) expressed this uncertainty: \u003cem\u003e\"I can't trust it. I don't know if that was real... The challenging thing is, like, that's a horrible thing to not know if it's real or not.\"\u003c/em\u003e\u003c/p\u003e\u003cp\u003eAs shown in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, participants' post-experience trajectories of change fell into three categories: predominantly positive integration (50%), mixed negative/positive change (28%), and predominantly negative or re-traumatization (22%). Those reporting positive trajectories often described profound healing despite initial distress: \u003cem\u003e\"I'm probably a much better person because of it\"\u003c/em\u003e (P9). Those with mixed trajectories acknowledged benefits alongside ongoing challenges: \u003cem\u003e\"Overall, it was a very healing experience. But... not having closure about it was harmful for me and my family\"\u003c/em\u003e (P3). Participants reporting negative trajectories described symptoms resembling re-traumatization: \u003cem\u003e\"I didn't cope well after it. I had a lot of problems with sleep, and I was having flashbacks\"\u003c/em\u003e (P7).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eTrajectories of Trauma-Related Psychedelic Experiences as Described in Interviews\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"4\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTrajectory of Change\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eDefinition\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eParticipants\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eExample Participant Reflections\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePredominantly Positive Integration\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eDespite the difficulty, the experience led to healing insights or improvements. Participants processed the resurfaced trauma and reported reduced trauma symptoms, personal growth, or positive life changes (e.g. seeking therapy, improved relationships). They often reframed the experience as a meaningful turning point.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e~\u0026thinsp;9 (50%) \u0026ndash; e.g. P1, P4, P9, P10, P11, P17, P18, etc.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003e\u0026ldquo;It was very healing, although it nearly killed me.\u0026rdquo;\u003c/em\u003e\u0026nbsp;(P4 \u0026rdquo;\u003cem\u003eI\u0026rsquo;m much happier, and my capacity for joy is much greater.\u0026rdquo;\u003c/em\u003e\u0026nbsp; (P1) \u003cem\u003e\u0026ldquo;I\u0026rsquo;m probably a much better person because of it.\u0026rdquo;\u003c/em\u003e\u0026nbsp;(P9)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eMixed Trajectory\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eThe experience had both beneficial and adverse aspects. Participants gained some insight or partial healing, but also experienced ongoing challenges (e.g. difficulty integrating certain elements, new anxieties). They might value some lessons from the experience but remain ambivalent or cautious.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e~\u0026thinsp;5(28%) \u0026ndash; e.g. P3, P6, P13, P15, P17.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003e\u0026ldquo;But yeah, so, overall, it was a very healing experience. But then... Having a door open and then not being able to have closure about it was harmful for me and my family.\u0026rdquo;\u003c/em\u003e (P3)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePredominantly Negative / Re-traumatization\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eThe experience was mainly harmful. It either reinforced the original trauma or added new trauma. Participants reported exacerbated symptoms (e.g. more frequent flashbacks, panic, insomnia) or emotional downturns lasting long after the session. They did not perceive a net benefit and often regretted or were traumatized by the psychedelic experience itself.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e~\u0026thinsp;4(22%) \u0026ndash; e.g. P2, P5, P7, P16.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003e\u0026ldquo;I was feeling really overwhelmed\u0026hellip; I worried that even shutting my eyes would take me back there.\u0026rdquo;\u003c/em\u003e(P2). \u003cem\u003e\u0026ldquo;I didn\u0026rsquo;t cope well after it. I had a lot of problems with sleep, and I was having flashbacks.\u0026rdquo;\u003c/em\u003e(P7) \u003cem\u003e\u0026ldquo;I just went into like a dark night of the soul for literally a year.\u0026rdquo;\u003c/em\u003e (P5)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv id=\"Sec15\" class=\"Section2\"\u003e\u003ch2\u003e[INSERT Table \u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e]\u003c/h2\u003e\u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe quantitative survey findings provided evidence that individuals who report a link between an early trauma and post-psychedelic extended difficulties, when compared with those who do not, are on average older, more likely to be diagnosed with a mental illness prior to the psychedelic experience, more likely to be taking psychedelics in a guided setting, more likely to believe that using psychedelics lead to benefits that outweigh the risk involved, and have a higher proportion of female.\u003c/p\u003e\u003cp\u003eIn terms of the age difference between the groups, one possible interpretation is that older participants may be more likely to reflect on earlier life experiences in the context of psychedelic difficulties. While the survey did not ask whether these traumatic events had been previously repressed or forgotten, this pattern may still align with developmental theories such as Hollis\u0026rsquo;s idea of midlife as a period when unconscious material becomes more salient or emotionally charged\u003csup\u003e\u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e\u003c/sup\u003e. However, further research is needed to determine whether age-related recall dynamics played a role in how trauma was interpreted in these experiences. We also found that participants who linked their post-psychedelic difficulties to early trauma were more likely to be in guided settings for the psychedelic experience. This can be interpreted as those with past trauma having a stronger motivation for safety and containment in their psychedelic work, and possibly an explicit intention to work on post-traumatic symptoms in a guided setting rather than to take the drug recreationally\u003csup\u003e\u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e\u003c/sup\u003e. Another interpretation in the opposite causal direction is that guided settings may create a therapeutic environment (therapeutic suggestibility) where repressed material, such as early trauma, is more likely to emerge (or be perceived to emerge) during the psychedelic experience.\u003c/p\u003e\u003cp\u003eThe higher proportion of females in the group linking trauma to difficulties could align with previous research that suggests women are more likely to experience early interpersonal trauma (e.g., sexual abuse) and to engage in help-seeking behaviors\u003csup\u003e\u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e43\u003c/span\u003e\u003c/sup\u003e. It may also reflect gendered differences in emotional expressivity and trauma disclosure in post-experience narratives\u003csup\u003e\u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e44\u003c/span\u003e\u003c/sup\u003e, and possible serotonergic sensitivity due to hormonal factors\u003csup\u003e\u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e45\u003c/span\u003e,\u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e46\u003c/span\u003e\u003c/sup\u003e. Goldner et al. also found that women were more likely to engage in \"tend-and-befriend\" coping rather than avoidance, which may reflect gendered differences in disclosure and help-seeking, and might partially explain the therapeutic-seeking and openness to guided use\u003csup\u003e\u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e47\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eA belief in the benefits of psychedelics is higher in the group with recalled trauma. This may stem from having had an experience in healing through catharsis or self-transformation, despite encountering difficulties. It could also reflect a form of post-traumatic growth, where participants retrospectively frame challenging experiences as meaningful or valuable, even when they involve resurfacing trauma\u003csup\u003e\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eIn terms of the post-psychedelic extended difficulties reported, those who re-experienced past trauma were significantly more likely to report emotional difficulties after the psychedelic experience than those who did not, but were less likely to report perceptual difficulties. This may also point to suggest different neural processing - possibly, this pattern might reflect differential engagement of affective vs. sensory systems; however, the present data cannot adjudicate mechanisms.\u003csup\u003e\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e,\u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e48\u003c/span\u003e,\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\u003cdiv id=\"Sec17\" class=\"Section2\"\u003e\u003ch2\u003eDiscussion of qualitative findings\u003c/h2\u003e\u003cp\u003eThe qualitative analysis supports previous findings that psychedelic experiences have the potential to heal or exacerbate trauma\u003csup\u003e\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e,\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e\u003c/sup\u003e. On the one hand, participants described how they facilitated emotional and somatic breakthroughs, as has been previously described in research \u003csup\u003e\u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e49\u003c/span\u003e\u003c/sup\u003e. On the other side, some participants conveyed that they led to emotional overwhelm and re-traumatization, where the set and setting were problematic and where there was little support for integration and navigating subsequent challenges.\u003c/p\u003e\u003cp\u003eThe themes elicited from the qualitative data capture various experiential features of the perceived link between early trauma and post-psychedelic extended difficulties. Theme 1, reported by 39% of participants, captured the experience of remembering past childhood trauma during the psychedelic experience and the direct emotional implications of this. Participants described how the psychedelic experience revealed what appeared to be repressed traumatic memories (of which some had no prior memory). They discussed how this brought profound emotional challenges and opportunities. This echoes the quantitative finding that emotional difficulties after the psychedelic episode were more frequent in the group reporting past trauma. The immediate aftermath for one participant (P5) included \u003cem\u003e\"a dark night of the soul for literally a year,\"\u003c/em\u003e demonstrating the potentially destabilizing nature of such revelations. Whether such experiences were a veridical recollection of past events was uncertain, particularly given that a proportion of participants had no prior memory of the event, and this uncertainty was itself anxiety-inducing for some. For example, P3's case shows this feature of being haunted by uncertainty. This represents prior work on this topic, which mentions that the lack of certainty - \u003cem\u003e\"not knowing if it's real or not\"\u003c/em\u003e - can become traumatic, leading to ongoing distress long after the session\u003csup\u003e\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eTheme 2, \u003cem\u003esymbolic/sensory re-embodiment of trauma\u003c/em\u003e (experienced by 22% of participants) captures the bodily, symbolic, and non-literal representation of trauma, which the participants interpreted as meaningfully linking to past adverse events. These physical manifestations can be interpreted as indirect representations of repressed or suppressed emotions that seek expression\u003csup\u003e\u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e50\u003c/span\u003e\u003c/sup\u003e. The therapeutic value of such experiences may lie in their ability to allow emotional processing without explicit recall of traumatic events\u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/sup\u003e. These experiences underscore psychedelics' capacity to engage trauma on a non-verbal level - effectively allowing a person to work through trauma feelings and responses without re-experiencing the original event. However, their indirect nature requires careful professional post-session support and integration to help facilitate healing.\u003c/p\u003e\u003cp\u003eTheme 3: \u003cem\u003efragmentation and confusion\u003c/em\u003e were experienced by 50% of our participants. It represents reports of how the psychedelic state can sometimes overwhelm an ability to cope, leading to a feeling of disintegration that may itself echo the feeling of being traumatized. For example, P15's experience suggests that even when participants know something important was processed through intense physical release, the nonverbal and strange nature of the experience can make it difficult to explain or integrate. Such cases may require extensive reflection or therapy afterward to construct meaning from the experience.\u003c/p\u003e\u003cp\u003eTheme 4 captured the varied post-experience trajectories from therapeutic integration to re-traumatization. The divergent trajectories reported (as summarized in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e) suggest that preparation, context, and support play crucial roles in determining whether psychedelic encounters with trauma lead to healing or further harm. These outcomes may also be shaped by factors such as attachment history, cultural framing, and the degree of interpersonal or therapeutic support available during or after the experience\u003csup\u003e\u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e51\u003c/span\u003e\u003c/sup\u003e. Generally, participants with positive outcomes (50%) had been prepared within a therapeutic framework or sought integration afterward, while those with adverse outcomes (22%) often lacked sufficient support. The meaning ascribed to the experience also appears critical. Even when the trip was extremely challenging, those who found meaning (like P9, who decided the experience revealed his calling to help others) tended to fare better than those who viewed it as \"just bad\" or meaningless suffering.\u003c/p\u003e\u003cp\u003eThe findings suggest that challenging psychedelic experiences involving the reactivation or recollection of past trauma need to minimize harms and maximize potential benefits. With appropriate preparation, setting, and follow-up integration, they can serve as opportunities for deep healing, providing exposure therapy or catharsis that frees people from past trauma\u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/sup\u003e. Without adequate support, such experiences risk re-traumatization\u003csup\u003e\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e,\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e\u003c/sup\u003e. Participants who experienced trips alone without any guide or subsequent therapy show how a lack of support can leave someone to cope with the fallout on their own, potentially worsening trauma symptoms. Conversely, those who actively engaged in integration work through psychotherapy, journaling, meditation, support groups, or deep personal reflection are more likely to report that they transform their challenging experiences into healing.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec18\" class=\"Section2\"\u003e\u003ch2\u003eLimitations and Future Directions\u003c/h2\u003e\u003cp\u003eSeveral notable limitations accompany this study. First, while the survey phase had a large dataset, the self-reported nature of past experiences and trauma experiences may lead to recall bias, social desirability bias, or underreporting, especially given the sensitive topic. Online administration further limits control over participant understanding and engagement. The qualitative phase allowed for richer exploration of trauma\u0026rsquo;s impacts but included only a small, non-random subset of the survey sample who were purposively sampled for reporting a link between childhood trauma and extended post-psychedelic difficulties. This targeted sampling may have introduced selection bias, as those who volunteered for interviews may have differed systematically from those who did not, who met the same criteria, for example, being more comfortable discussing trauma or having fewer extreme experiences. As such, the findings from interviews may not be representative of the broader population surveyed. Moreover, conducting interviews online can limit rapport and nonverbal communication, both of which are crucial in sensitive discussions. Theme prevalences reported for the 18 interviews are descriptive of this purposively sampled subset. They should not be generalized to the Phase 1 cohort or wider populations. Finally, both phases rely on internet access and digital literacy, which may potentially exclude marginalized populations and introduce sample bias. Overall, while the mixed-methods design enriches the understanding of trauma, these methodological limitations must be carefully addressed.\u003c/p\u003e\u003cp\u003eFuture research in this area will benefit from longitudinal studies with existing cohorts, such as the Dunedin study\u003csup\u003e\u003cspan citationid=\"CR52\" class=\"CitationRef\"\u003e52\u003c/span\u003e\u003c/sup\u003e. This would allow for objective information about adverse childhood experiences that were gathered at the time to be cross-checked against reports of such experiences from those working with psychedelics. Another important step will be to gain the views of experts and practitioners working in the field of psychedelic integration to collate their knowledge of best practice when working with individuals processing perceived recollections of, or emotions associated with, past trauma.\u003c/p\u003e\u003cp\u003eThe study focused on people who believed an earlier experience of trauma led to post-psychedelic difficulties. It did not ask how many of these earlier experiences of trauma were recalled for the first time during the psychedelic experience. Nor did it focus directly on the question: \u0026lsquo;How sure are you that this earlier experience of trauma really happened?\u0026rsquo; Although some interviewees voluntarily shared their feelings on the topic, expressing a range of views from very certain to not-so-certain. We did not seek external corroboration of recalled events; findings concern subjective recall and meaning-making rather than verification of historical accuracy. The degree of certainty regarding the truth of the memory may be related to the degree of catharsis experienced by the person, although this requires further exploration in future studies. Certainty is not the same as truth - there remains the question of whether or how often recovered memories of early trauma during psychedelic experiences are genuine and veridical, when they are hallucinations, how a person (and their therapist) can discriminate between genuine memory and hallucination, and how to live with the possibility of not knowing for sure. There is also the question, worthy of future investigation, of whether memories of early trauma could be suggested to or implanted in individuals while they are in suggestible psychedelic states, by guides or therapists overly invested in the \u0026lsquo;trauma catharsis\u0026rsquo; theory of psychedelic healing or more broadly the \u0026lsquo;trauma culture\u0026rsquo;.\u003c/p\u003e\u003cp\u003eIn summary, this study points towards the central importance of developing a trauma-informed and trauma-literate approach to working with psychedelics that can be applied across clinical and non-clinical settings. The benefits of this will be threefold. Firstly, it will allow for evidence-based support for the therapeutic and existential challenges that emerge for individuals who are re-experiencing or processing what appear to be memories of past trauma. Secondly, this will provide a foundation of support for those with PTSD, such as army veterans, who seek therapeutic help through psychedelics\u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/sup\u003e. Thirdly, a trauma-informed approach to psychedelic work will help to mitigate against the chance that the psychedelic experience itself is traumatic\u003csup\u003e\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e\u003c/sup\u003e. Our qualitative findings suggest that the trajectories of change following the experience are influenced by the context and care surrounding it. A trauma-informed psychedelic culture will maximize the conditions for integration and support, so that encounters with past events (or what may be subjectively construed as such) can be transformed into a step toward wholeness rather than a re-wounding.\u003c/p\u003e\u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements\u0026nbsp;\u003cbr\u003e\u003c/strong\u003eThe authors are deeply grateful to all the individuals who participated in this study. We thank the survey respondents for sharing their experiences and insights, and especially the interview participants who courageously recounted complex and often painful journeys. Their openness and honesty made this research possible. We also acknowledge the Challenging Psychedelic Experiences Project (CPEP) for its foundational support and the broader psychedelic research community for its ongoing commitment to safety, integrity, and inquiry.\u003cbr\u003e\u0026nbsp;\u003cbr\u003e\u003cstrong\u003eAuthor Contributions\u003c/strong\u003e\u0026nbsp;\u003cbr\u003e\u003cstrong\u003eGS:\u003c/strong\u003e Conceptualization; Methodology; Formal Analysis; Investigation; Writing \u0026ndash; Original Draft; Writing - Review \u0026amp; Editing; Visualization; Project Administration.\u0026nbsp;\u003cbr\u003e\u003cstrong\u003eNT:\u003c/strong\u003e Data Curation; Investigation.\u003cbr\u003e\u003cstrong\u003eMS:\u003c/strong\u003e Writing \u0026ndash; Review \u0026amp; Editing.\u0026nbsp;\u003cbr\u003e\u003cstrong\u003eJE:\u003c/strong\u003e Conceptualization; Investigation; Writing \u0026ndash; Review \u0026amp; Editing. Project Administration.\u003cbr\u003e\u003cstrong\u003eOR:\u003c/strong\u003e Supervision; Conceptualization; Investigation; Methodology; Formal Analysis; Writing - Review \u0026amp; Editing.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u0026nbsp;\u003cbr\u003e\u003c/strong\u003eThis research was conducted as part of the Challenging Psychedelic Experiences Project (CPEP), a broader initiative supported by the William G. Nash Foundation and the Sarlo Family. However, this specific study did not receive any direct funding from these or other sources. The funders had no role in the design, data collection, analysis, interpretation, or writing of this manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting Interests\u0026nbsp;\u003cbr\u003e\u003c/strong\u003eThe authors declare no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Availability\u0026nbsp;\u003cbr\u003e\u003c/strong\u003eThe datasets generated and/or analyzed during the current study are not publicly available due to the sensitive nature of trauma-related narratives and the need to protect participant confidentiality. De-identified excerpts or summary data may be available from the corresponding author upon reasonable request and pending ethical approval.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eMitchell, J. M. \u0026amp; Anderson, B. T. 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Gender differences in attitudes towards trauma/abuse disclosure. \u003cem\u003eThe Plymouth Student Scientist\u003c/em\u003e \u003cstrong\u003e14\u003c/strong\u003e, 669\u0026ndash;691 (2021).\u003c/li\u003e\n\u003cli\u003eGoldner, L., Lev-Wiesel, R. \u0026amp; Simon, G. Revenge Fantasies After Experiencing Traumatic Events: Sex Differences. \u003cem\u003eFront. Psychol.\u003c/em\u003e \u003cstrong\u003e10\u003c/strong\u003e, (2019).\u003c/li\u003e\n\u003cli\u003eKelly, J. R. \u003cem\u003eet al.\u003c/em\u003e Psychedelic Therapy\u0026rsquo;s Transdiagnostic Effects: A Research Domain Criteria (RDoC) Perspective. \u003cem\u003eFront. Psychiatry\u003c/em\u003e \u003cstrong\u003e12\u003c/strong\u003e, 800072 (2021).\u003c/li\u003e\n\u003cli\u003eRoseman, L. \u003cem\u003eet al.\u003c/em\u003e Emotional breakthrough and psychedelics: Validation of the Emotional Breakthrough Inventory. \u003cem\u003eJ Psychopharmacol\u003c/em\u003e \u003cstrong\u003e33\u003c/strong\u003e, 1076\u0026ndash;1087 (2019).\u003c/li\u003e\n\u003cli\u003eVan der Kolk, B. A. \u003cem\u003eThe Body Keeps the Score: Brain, Mind and Body in the Healing of Trauma\u003c/em\u003e. (Penguin Books, New York, NY, 2015).\u003c/li\u003e\n\u003cli\u003eCassidy, E. K., Dupuis, D., Timmermann, C. \u0026amp; Granqvist, P. Psychedelics, attachment, and enculturation dynamics: Prospects and challenges. \u003cem\u003eJournal of Psychedelic Studies\u003c/em\u003e (2025) doi:10.1556/2054.2025.00459.\u003c/li\u003e\n\u003cli\u003eThe Dunedin Study - Dunedin Multidisciplinary Health \u0026amp; Development Research Unit. https://dunedinstudy.otago.ac.nz/ (2025).\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Psychedelics, trauma, adverse life experiences, memory, PTSD, mixed methods, re-traumatisation, extended difficulties","lastPublishedDoi":"10.21203/rs.3.rs-7255362/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7255362/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis mixed-methods study investigated the relationship between recalled childhood trauma during psychedelic experiences and subsequent extended psychological difficulties. While psychedelics can facilitate emotional processing of autobiographical material, a minority experience adverse effects or re-traumatization when trauma resurfaces. Phase 1 surveyed 608 individuals who experienced post-psychedelic difficulties lasting beyond acute effects. Those linking difficulties to early trauma (41.8%) were significantly older, more often female, were more likely to report a prior mental-illness diagnosis, and were more likely to use psychedelics in guided settings compared to those without trauma links. They also reported significantly more emotional difficulties but fewer perceptual difficulties after the experience. Phase 2 involved semi-structured interviews with 18 purposively selected participants. Reflexive thematic analysis identified four themes: direct trauma re-experiencing (39% of participants, including some with no prior memory of events), symbolic/somatic re-embodiment (22%), fragmentation and confusion (50%), and varied post-experience trajectories. Outcomes ranged from predominantly positive integration (50%) to mixed effects (28%) to re-traumatization (22%). The study highlights uncertainty around memory veridicality as a source of ongoing distress for some participants. Findings emphasize the critical need for trauma-informed approaches to psychedelic use, stressing appropriate preparation, supportive settings, and robust integration support to maximize therapeutic potential while preventing re-traumatization.\u003c/p\u003e","manuscriptTitle":"The experience of recalled trauma during psychedelic experiences and perceived links to subsequent extended difficulties: A mixed-methods study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-08-21 06:30:44","doi":"10.21203/rs.3.rs-7255362/v1","editorialEvents":[{"type":"communityComments","content":1},{"type":"decision","content":"Revision requested","date":"2025-10-01T15:14:50+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"253611849209007374421129886087183907190","date":"2025-10-01T12:31:43+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"242811601353304116918981711185869185729","date":"2025-10-01T12:13:08+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-10-01T10:37:56+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"336855620835390320289337631876941594024","date":"2025-09-27T03:28:33+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"237668514645739626315041554310901061718","date":"2025-09-26T05:32:28+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-09-12T12:53:54+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-09-08T14:59:23+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"300710039468986143531229774202591849692","date":"2025-09-08T12:33:31+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"120737793264743595524644298181752954391","date":"2025-09-08T12:06:27+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-09-06T04:53:40+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-09-03T05:24:13+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-08-11T15:01:55+00:00","index":"","fulltext":""},{"type":"submitted","content":"Scientific Reports","date":"2025-08-11T14:58:32+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"d8b9a996-4589-4473-ac1d-39a684849650","owner":[],"postedDate":"August 21st, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[{"id":52988654,"name":"Health sciences/Health care"},{"id":52988655,"name":"Health sciences/Medical research"},{"id":52988656,"name":"Biological sciences/Psychology"},{"id":52988657,"name":"Social science/Psychology"}],"tags":[],"updatedAt":"2025-12-01T16:14:53+00:00","versionOfRecord":{"articleIdentity":"rs-7255362","link":"https://doi.org/10.1038/s41598-025-26198-4","journal":{"identity":"scientific-reports","isVorOnly":false,"title":"Scientific Reports"},"publishedOn":"2025-11-27 15:57:10","publishedOnDateReadable":"November 27th, 2025"},"versionCreatedAt":"2025-08-21 06:30:44","video":"","vorDoi":"10.1038/s41598-025-26198-4","vorDoiUrl":"https://doi.org/10.1038/s41598-025-26198-4","workflowStages":[]},"version":"v1","identity":"rs-7255362","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7255362","identity":"rs-7255362","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}