Cooperative behaviour in kidney donors and transplant candidates on the Prisoner’s Dilemma task

Cooperative behaviour in kidney donors and transplant candidates on the Prisoner’s Dilemma task | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Cooperative behaviour in kidney donors and transplant candidates on the Prisoner’s Dilemma task Ioanna Zioga, Stathis Tsiakas, George Kosteletos, Orestis Giannakopoulos, and 5 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4341728/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Interpersonal cooperation is a prerequisite for individual and social well-being, while organ donation has a plethora of moral implications beyond its medical relevance. However, little has been known about whether kidney donors exhibit higher cooperation in morally-laden decisions. Our study aims to fill this gap by comparing cooperation in kidney donors vs. transplant candidates using a computerized Prisoner’s Dilemma task. Participants were presented with dilemmas and were required to cooperate with or defect against a fictional partner (computer). Participants’ degree of cooperation was modulated based on the computer’ strategy (higher/lower cooperation for more reciprocative/conflicting strategies). There was a trend for donors to be faster than transplant candidates. Interestingly, the higher the degree of cooperation following reward, the lower the degree of cooperation following punishment for transplant candidates. The latter were faster when cooperating after reward, but slower when cooperating after punishment. Our findings provide evidence that kidney donors are more decisive with regard to cooperation vs. competition. On the contrary, transplant candidates show a stronger dependence on their partner’s behaviour. Overall, our results suggest that cooperative behaviour differs between kidney donors and transplant candidates, and that the Prisoner’s Dilemma task could provide a suitable tool to study those patterns. Biological sciences/Psychology/Human behaviour Health sciences/Diseases/Kidney diseases/Chronic kidney disease Prisoner’s Dilemma kidney transplant kidney donor cooperation moral behaviour. Figures Figure 1 Figure 2 1. Introduction Cooperation is an unselfish expression of the human social nature, although it can be also achieved between selfish but rational agents who might recognize mutual benefits due to the possibility of reciprocity [ 1 , 2 ]. It indicates refraining from a higher individual benefit to achieve a collective benefit, which however requires to be reciprocated [ 3 ]. Previous studies have shown that reciprocity is also required for sustained cooperative behavior among humans and other animals [ 4 – 6 ]. Living donor kidney transplant is the optimal treatment for most patients with end-stage kidney disease. Data show that donors act like gift givers, donating voluntarily for altruistic reasons to help restore the health of a loved one [ 7 , 8 ]. Prospective organ recipients are concerned about the health and wellbeing of the donor candidate and find the offer emotionally burdensome [ 9 ]. Organ recipients usually feel unduly indebted thus expressing gratitude to the donor as a form of reciprocation [ 10 ]. Organ donation might thus be considered an example of high-cost cooperation [ 11 ]. However, little is known regarding cooperation in kidney donor and transplant candidates outside the organ transplantation setting. Do kidney donors exhibit more cooperative behaviour than transplant recipients? Is behaviour affected by the strategy followed by their partner? How is cooperation influenced by the perception of reward or punishment? The present study investigated cooperative behaviour in kidney donor and transplant candidates using a computerized version of a standard moral dilemma task, the Iterated Prisoner’s Dilemma. The Prisoner’s Dilemma (PD) task traditionally refers to a situation in which two people suspected of committing a crime are questioned independently to admit or deny guilt for the crime [ 12 ]. If both deny guilt, they can minimize jail time (higher reward), but, if both admit guilt, they will serve jail time (lower reward). If they do not respond the same way, one will serve far more jail time, while the other will be set free. Notably, choices in the PD are usually associated with cooperative and competitive intentions [ 13 ]. For instance, making mutually beneficial choices shows an intention to maximize the reward of both players by sacrificing the highest personal reward [ 14 ]. On the other hand, making self-interested decisions creates competitiveness and a goal to outperform the other player [ 15 ]. In case of many PD iterations, players get information about the other partner’s intentions as the iterations evolve over time [ 12 ]. The PD has been widely used to study the relationship between cooperation and several personality and psychological aspects, such as personality traits [ 16 ], empathy [ 17 ], and traits of psychopathy [ 18 ], borderline personality and bipolar disorder [ 19 ] and depression [ 20 ]. The dynamics of cooperation are seen as relying on decision-making, feedback appraisal, perspective-taking and judgement for the return-benefits it bears for the agent [ 21 – 23 ]. Our goal here was to study how cooperation differs between kidney donors and transplant candidates, and how their perception of reward or punishment by the other person affected their behaviour. The current study extends past research by implementing a computerized PD game in which participants who are either kidney donor or transplant candidates play a number of PD iterations with the computer as their partner. As mentioned earlier, cooperation requires trust in reciprocation [ 4 ], PD thus constitutes a suitable tool to create a conflict by manipulating someone’s willingness to cooperate. Furthermore, the computer was programmed to follow different strategies thus offering better control of the conditions to which participants were exposed. More specifically, there were blocks of five different strategies: 1) Pavlov (the computer keeps the same move when winning and switches when losing), 2) Always cooperate (the computer cooperates in every trial), 3) Pavlov random (random moves were introduced in previous strategy), 4) Always defect (the computer defects in every trial), and 5) Tit-for-tat (the computer reciprocates the participant’s exact move). Notably, participants were unaware of the fact that the computer was programmed according to these strategies. We recorded participants’ responses and reaction times throughout the task. To explore how reward and punishment affects behaviour, we identified “reward trials” as trials following two consecutive trials in the first of which the participant cooperated and the second of which the computer cooperated (i.e. the participant might have perceived the computer’s cooperation as a reward after the participant’s cooperation). We also identified “punishment trials” as trials following two consecutive trials in the first of which the participant defected and the second of which the computer defected (i.e. the participant might have perceived the computer’s defect as punishment due to their own previous defect). With regard to our hypotheses, we expected that both kidney donor and transplant candidates would cooperate more during reciprocating (pavlov, always cooperate, tit-for-tat) than during selfish strategies (pavlov random, always defect), due to the effect of the partner’s intention on cooperative behaviour. Similarly, we expected higher degree of cooperation following perceived reward than punishment. Our main question was whether compared to transplant recipients, kidney donors would show greater or equal degree of cooperation. On the other hand, we could argue that kidney donors would be more cooperative in PD, potentially reflective of a more general incline towards altruism and collective benefit outside the realm of organ donation. However, it is known that the motivation between organ donation is linked to empathy and compassion (e.g. in the case of familial donation: [ 7 , 8 ]). As donors seem to be driven by emotions, it is also possible that they would show an equal degree of cooperation in PD, due to the absence of emotional context or loved person that needs their help. 2. Materials and Methods 2.1. Participants Forty-eight adults (18 female) aged between 21 and 70 years old ( M ± SD age of 48.76 ± 13.02 years) participated in the experiment, of whom 21 were kidney donor candidates and 27 were kidney transplant candidates. Donors were aged 53.00 ± 8.97 and recipients were aged 45.52 ± 14.81. Age was not significantly different between groups ( t (35) = 1.78, p = .084). Biological gender was not balanced between groups, as there were 15 female donors, but only 3 female recipients. According to inclusion criteria, subjects needed to be primary education graduates and have a decent understanding of Greek language. Prior to participation, all subjects were interviewed by a psychiatrist in order to exclude the presence of any major clinical psychopathology or cognitive decline. The inclusion criteria were based on the assumption that the iterated procedure of the PD implies that every participant has the ability to perform logically consistent reasoning, associated with the optimization of one’s reward [ 24 , 25 ]. The study was performed in the psychophysiology laboratory of the First Department of Psychiatry, “Eginition Hospital”, National and Kapodistrian University of Athens, Medical School, Greece in collaboration with the Department of Nephrology and Renal Transplantation, “Laikon” Hospital, National and Kapodistrian University of Athens, Medical School, Greece. The study was approved by the local ethics committee (Number: 653, 7/11/2019). The experiment was performed in accordance with relevant guidelines and regulations. All participants were extensively informed about the procedure and gave written consent for participation. 2.2. Prisoner’s dilemma The Prisoner’s Dilemma (PD), first introduced by the mathematicians Melvin Flood and Melvin Dresher and given its final form and name by Albert W. Tucker, comprises a tool to study cooperation and defection [ 26 ]. Traditionally, participants are presented the following scenario: “Two prisoners, A and B, suspected of committing a robbery together, are isolated and urged to confess. Each is concerned only with getting the shortest possible prison sentence for himself; each must decide whether to confess without knowing his partner’s decision. Both prisoners, however, know the consequences of their decisions: 1) if both confess, both go to jail for five years; 2) if neither confesses, both go to jail for one year (for carrying concealed weapons); and 3) if one confesses while the other does not, the confessor goes free (for turning state’s evidence) and the silent one goes to jail for 20 years.” Here, we used a computerized version of the Iterative PD. The game was played between a participant and a computer (PC). Participants were exposed to the dilemma on several successive rounds (trials), and were required to select between two options: “cooperate” (protect their partner) or “defect” (testify against their partner). Thus, there are four possible combinations of choices on behalf of the two protagonists (participant-PC), depending on which some points are given: 1) Cooperate-Cooperate (3 points), 2) Defect-Defect (1 point), 3) Cooperate-Defect (0 points), and 4) Defect-Cooperate (5 points). In each trial, the dilemma is set again and both the participant and the PC make a simultaneous move. After the moves have been made, the participant is presented with their own and the PC’s score of that trial, their own and the PC’s cumulative score over all trials so far, their own and the PC’s choice at that trial, and the pay-off matrix. The pay-off matrix is a 2-by-2 matrix, whose rows are labelled by the participants’ options “Cooperate” or “Defect” and its columns by the PC’s options. Each element of the matrix consists of the pair of points that the participant and the PC will receive in the corresponding case. The PD task constituted of 5 blocks of 25 trials each. Each block followed one of five strategies: 1) Pavlov (the computer keeps the same move when winning and switches when losing), 2) Always cooperate (the computer cooperates in every trial), 3) Pavlov random (random moves were introduced in previous strategy), 4) Always defect (the computer defects in every trial), and 5) Tit-for-tat (the computer reciprocates the participant’s exact move). The order of the strategy blocks was randomized across participants. Finally, participants were not aware how many trials or blocks the experiment was comprised of, in order to avoid the end-game effect [ 27 ]. 2.3. Data analysis Because the participants were not prompted for the change of strategy every 25 trials, the first 3 trials of each strategy were excluded from all analyses, as it was improbable that participants could notice the change of strategy already. Reaction times and cooperation. First, we wanted to investigate potential differences in reaction times and cooperation between donors and recipients. Reaction times were averaged over trials. Cooperation was computed as the percentage of trials participants showed cooperative behaviour. Two 2 (group: donors, recipients) x 5 (strategy: Pavlov, Always cooperate, Pavlov random, Always defect, Tit-for-tat) repeated measures ANOVAs were conducted separately for reaction times and cooperation. Reaction times and cooperation in reward and punishment. We investigated how task performance differed in response to perceived reward and punishment. “Reward trials” were considered those following two consecutive trials in the first of which the participant cooperated and the second of which the computer cooperated, whereas “punishment trials” were those following two consecutive trials in the first of which the participant defected and the second of which the computer defected. Two 2 (group: donors, recipients) x 2 (condition: reward, punishment) repeated measures ANOVAs were performed on reaction times and cooperation, separately. Furthermore, Spearman’s rho correlations were tested between reaction times for punishment and reward, and between percentage of cooperative responses for punishment and reward, separately for donors and recipients. 3. Results 3.1. Reaction times and cooperation in the Prisoner’s Dilemma A 2 x 5 repeated measures ANOVA with group and strategy as independent variables revealed no significant main effect or interaction between the variables (strategy: F (4,184) = 1.15, p = .34; group: F (1,46) = .72, p = .40; strategy X group: F (4,184) = 1.71, p = .15) (Fig. 1 A). Throughout the course of the session (Fig. 1 B), there was a trend for recipients to be slower than donors, but that was not significant (trials 20–30: t (46) = -1.96, p = .056). As expected, participants’ degree of cooperation varied between strategies (Fig. 1 C). This was confirmed by a repeated measures ANOVA showing a significant main effect of strategy ( F (4,184) = 9.211, p < .001). Pairwise contrasts revealed that this was due to participants cooperating more in the Always cooperate condition compared to Always defect ( t (47) = 4.226, p < .001) and Tit for Tat ( t (47) = 4.381, p < .001), the Tit for Tat condition compared to Always defect ( t (47) = 3.092, p = .003), the Pavlov compared to Always defect ( t (47) = 4.635, p < .001) and Random ( t (47) = 3.975, p .4). 3.2. Behaviour related to reward and punishment We investigated how task performance differed in response to perceived reward and punishment. “Reward trials” were considered those following two consecutive trials in the first of which the participant cooperated and the second of which the PC cooperated, whereas “punishment trials” were those following two consecutive trials in the first of which the participant defected and the second of which the PC defected. A 2 (donors, recipients) x 2 (reward, punishment) repeated measures ANOVA on reaction times showed no significant effect or interaction between the variables ( p > .4) (Fig. 2 A, left). A 2 (donors, recipients) x 2 (reward, punishment) repeated measures ANOVA on percentage of cooperation revealed a significant main effect of condition ( F (1,44) = 73.805, p < .001). Pairwise contrasts showed that this was due to higher cooperation following reward than punishment ( t (45) = 8.778, p .9) (Fig. 2 A, right). Finally, we conducted Spearman’s rho correlations between reaction times and percentage of cooperative responses following reward vs. punishment. Results revealed significant positive correlations between reaction times for punishment and reaction times for reward in both groups (donors: rho = .537, p = .015; recipients: rho = .554, p = .003) (Fig. 2 B). Furthermore, the higher the percentage of cooperation following reward, the lower the percentage of cooperation following punishment, but only for recipients ( rho = − .489, p = .011) (donors: p = .4). For recipients, the more they cooperated, the faster they responded following reward ( rho = − .458, p = .019) (donors: p = .6) (Fig. 2 C), while the more they cooperated, the slower they responded following punishment ( rho = .603, p = .001) (donors: p = .5) (Fig. 2 D). 4. Discussion In this study, we investigated cooperative behaviour in kidney donor and transplant candidates using a standard moral dilemma task, the Prisoner’s Dilemma (PD). The current study extends past research by implementing a computerized PD game in which participants who are either kidney donor or transplant candidates play a number of PD iterations with the computer as their partner. Τhe computer was programmed to follow different strategies which were more or less cooperative or conflicting. We analyzed reaction times and degree of cooperation following reward vs. punishment in kidney donor and transplant candidates. We answer our research questions by demonstrating the following key findings: 1) Confirming the effect of the partner’s intention, participants’ degree of cooperation was modulated based on the strategy of the computer (higher/lower cooperation for more reciprocative/conflicting strategies), and was higher following reward than punishment; 2) There was a trend for donors to be faster than recipients, while in both groups reaction times following reward and punishment were correlated; and 3) Recipients responded equally strongly to reward and punishment as the higher the cooperation following reward, the lower the cooperation following punishment, which was also reflected in faster (slower) reaction times for reward (punishment), whereas donors did not show correlations between cooperation to reward and punishment. Overall, our findings contribute to the investigation of the psychological and cognitive features of kidney donors. As expected, participants’ degree of cooperation was modulated based on the strategy of the computer, namely both kidney donor and transplant candidates similarly cooperated less during selfish behaviour. More specifically, we observed higher degree of cooperation for more reciprocative strategies, i.e. pavlov, always cooperate, tit-for-tat, whereas there was lower cooperation for conflicting strategies, i.e. pavlov random, always defect. This indicates that participants’ willingness to cooperate with others changes as a function of the nature of their relationships, namely selfish treatment triggered retaliation. Previous studies have showed that older adults tend to handle emotion regulation in interpersonal conflict passively [ 28 , 29 ] and behave assertively in situations that elicit anger or annoyance [ 29 ]. The age distribution of our sample was above the younger adults who are usually considered until 25 years old. Therefore, our finding is in line with previous work showing that people, independently of their age, tend to adjust their cooperation levels based on the behaviour of their partner [ 30 ]. Additionally, this is further corroborated by our other finding that cooperation degree was higher following reward compared to punishment. In particular, this provides evidence for two points: 1) the measures of “reward” and “punishment” that we constructed indeed represented the perception of participants and thus affected their subsequent decisions; and 2) it confirms the observation that cooperation is modulated by the perceived intention of the partner’s reciprocative or selfish behaviour [ 23 ]. Our aforementioned findings did not significantly differ between groups, suggesting that cooperative performance in the PD is not affected by the process of kidney donation or receival. Future studies are needed to investigate whether kidney donor and transplant candidates are differentiated in other aspects of morally-laden behaviour, potentially using a different kind of task. Furthermore, there was a trend for donors to be faster than recipients, which was however not statistically significant. First, it is possible that this did not reach significance due to the low sample size in our study. Further studies employing a larger sample size are needed to test this possibility. One explanation could lie on possible cognitive impairments of transplant candidates compared to kidney donors [ 31 ]. Indeed, cognitive impairment is common in patients undergoing hemodialysis [ 32 ]. The most affected domains are executive functions and speed of processing [ 33 ]. Another speculation could lie in an overall tendency of transplant candidates to be more suspicious and show less trust with regard to the motives of other individuals, which might have led them to take more time to make a decision that taps onto mutual trust and the relationship between the partners [ 34 ]. Additionally, we observed that in both groups reaction times following reward and punishment were correlated. This indicates that decision speed was not differentiated at the level of perceived reward or punishment by the other player/computer. Interestingly, transplant recipients’ behaviour was correlated between reward and punishment: the higher the degree of cooperation following reward, the lower the degree of cooperation following punishment. Furthermore, the more recipients cooperated following reward, the faster they responded, while the more they cooperated following punishment, the slower they responded. The transplant candidates’ hesitancy to cooperate after punishment may be due to their increased sense of vulnerability [ 35 – 37 ], leading to a higher level of depression and concerned stance (e.g. somatic concerns) compared to kidney donor candidates [ 38 ]. In this view, recipients’ hesitancy to proceed with an altruistic choice lies on hesitancy to proceed with a course of action that will increase their vulnerability. On the contrary, kidney donors did not show correlations neither between the degree of cooperation following reward and punishment nor between the degree of cooperation and reaction times. We will provide alternative explanations for these results. First, it seems like transplant recipients might have a strong preference for reward together with a strong dislike for punishment. In addition, the observation that transplant recipients cooperated faster after reward, whereas they cooperated slower after punishment, indicates that it took more time for them to cooperate after punishment. This delay might be related to being less inclined to cooperate after punishment. Nevertheless, previous studies investigating decision-making in moral dilemmas have assumed that players think less to make intuitive decisions and longer to make deliberate decisions, and thus concluded that the type of decisions with smaller reaction times are intuitive and those with the longer reaction times are deliberate [ 39 – 41 ]. The absence of the aforementioned effects for kidney donor candidates shows that they were more decided to cooperate independently of whether their partner/computer rewarded or punished them. This is in line with the notion that organ donation resembles gift giving via the voluntary will to help someone for altruistic reasons [ 7 , 8 , 11 ]. It is also interesting to highlight that numerous studies have shown that most organ donors make an instantaneous decision to donate with little or no deliberation and have no regrets about doing so [ 42 , 43 ]. Another relevant point here refers to the personality characteristics of kidney donor candidates. Kidney donors have been observed to be higher in agreeableness and lower in neuroticism compared to the general population [ 44 , 45 ]. Agreeableness includes cooperativeness and a prosocial, forgiving orientation, while low neuroticism is linked to emotional stability and low vulnerability to stress. People with these characteristics might be more willing to donate, as agreeableness and neuroticism play an important role in social contexts [ 44 ]. Another possibility could be that donors’ altruistic behaviour was a reflection of social desirability, which potentially underlines their decision for organ donation [ 46 , 47 ]. Therefore, our findings provide evidence that donors are more decisive during decision-making on dilemmas with regard to cooperation vs. competition, whereas recipients show a dependence on their partner’s behaviour, as they cooperate more when their partner rewards them, but cooperate less when their partner punishes them. Future studies are needed to directly investigate potential associations between personality and cooperation in the prisoner’s dilemma in organ donors and recipients. Overall, we believe that our findings shed light on the psychological and cognitive characteristics of kidney donors, which is fundamental to the optimization of their psycho-social management and support [ 48 – 50 ]. Crucially, this issue has clear moral implications linked to the principles of autonomy and justice [ 51 ]. Our study is not without limitations. First, biological sex was not balanced between groups, with the majority of donors being females whereas recipients being mostly males. Indeed, previous work has revealed a gender disparity in living renal transplant donation, namely that the vast majority of donors are females, which might be related to social desirability stemming from societal pressure [ 9 , 52 ], although not all research converges to this hypothesis [ 53 ]. Second, our sample size was limited which means we might have not have been able to detect smaller effect sizes. Third, a healthy group not involved in the kidney transplant procedure would be necessary to serve as a control, in order to test whether the effects identified in the kidney donor and transplant candidates would also be present in a sample of healthy adults. This would be especially useful for strengthening the findings on differences between groups with regard to reward and punishment. Declarations Competing interests The authors declare no competing interests. Funding The study was funded by the Regional Governor of Attica and co-funded by the Athanasios and Marina Matinou Foundation (AMMF) – a non-profit civil company ‘AEGEAS’. Author Contribution I.Z.: participated in data analysis, participated in the writing of the paper; S.T.: participated in data analysis, participated in the writing of the paper; G.K.: participated in research design, contributed new reagents or analytic tools, participated in the writing of the paper; O.G.: participated in research design, participated in the performance of the research; V.Z.: participated in data analysis, participated in the writing of the paper; P.C.P.: participated in research design, participated in the writing of the paper; G.V.: participated in research design, participated in the performance of the research, contributed new reagents or analytic tools; C.P.: participated in research design, contributed new reagents or analytic tools, participated in the writing of the paper; I.B.: participated in research design, participated in the writing of the paper, provided access to participants. 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C., Elswick, R., Sargeant, C. C. & Scott, S. Attitude, self-image, and quality of life of living kidney donors. Nephrology Nursing Journal 27, 43–50 (2000). De Pasquale, C. et al. Patterns of personality in living kidney donors. in vol. 48 319–322 (Elsevier, 2016). De Pasquale, C. et al. Psychological and psychopathological aspects of kidney transplantation: a systematic review. Frontiers in psychiatry 11, 106 (2020). Kumnig, M. & Jowsey-Gregoire, S. Preoperative psychological evaluation of transplant patients: challenges and solutions. Transplant Research and Risk Management 35–43 (2015). Olbrisch, M. E., Benedict, S. M., Ashe, K. & Levenson, J. L. Psychological assessment and care of organ transplant patients. Journal of consulting and clinical psychology 70, 771 (2002). Chironda, G. & Bhengu, B. Ethical, legal and cultural implications in the management of chronic kidney disease (CKD) patients: A critical review of literature. Transactions of the Royal Society of South Africa 71, 137–143 (2016). Zimmerman, D., Donnelly, S., Miller, J., Stewart, D. & Albert, S. E. Gender disparity in living renal transplant donation. American Journal of Kidney Diseases 36, 534–540 (2000). Achille, M., Soos, J., Fortin, M., Pâquet, M. & Hébert, M. Differences in psychosocial profiles between men and women living kidney donors. Clinical transplantation 21, 314–320 (2007). Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4341728","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":304862350,"identity":"58207d95-dc20-49c3-aaaf-b96ed0c4dae5","order_by":0,"name":"Ioanna Zioga","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA6klEQVRIiWNgGAWjYBACxgYIzQNiPwAx+EjRwmwAYrCRYiObBJgkpIy5vfnZ44KaOhl+/sXPKr/m2MmwMTA/fHQDn8N6jpkbzzjGxiM545nZbdltyUCHsRkb5+DTMiPBTJqHjYfH4MYBs9uS25iBWnjYpPFrSf8mzfNPAqjl+LdiyW31xGjJMZPmbTPgMTjfY8b4cdthIrT0nCmT5u1LAPqFp1iacdtxHjZmAn4xbG/fJs3zrc6en//4xo8/t1Xb87M3P3yMV0sDjCWRwMAMilAGZjzKQUAezuI/wMD4g4DqUTAKRsEoGJkAAOvYP9Zx96KBAAAAAElFTkSuQmCC","orcid":"","institution":"University Mental Health, Neurosciences and Precision Medicine Research Institute “COSTAS STEFANIS”, (UMHRI)","correspondingAuthor":true,"prefix":"","firstName":"Ioanna","middleName":"","lastName":"Zioga","suffix":""},{"id":304862351,"identity":"1756dd40-36fe-4948-95a2-d867c8909053","order_by":1,"name":"Stathis Tsiakas","email":"","orcid":"","institution":"Clinic of Nephrology and Renal Transplantation, Laiko General Hospital, Medical School, National and Kapodistrian University of Athens","correspondingAuthor":false,"prefix":"","firstName":"Stathis","middleName":"","lastName":"Tsiakas","suffix":""},{"id":304862352,"identity":"4c75d42f-49fa-43cd-89e6-cb5d5583b749","order_by":2,"name":"George Kosteletos","email":"","orcid":"","institution":"University Mental Health, Neurosciences and Precision Medicine Research Institute “COSTAS STEFANIS”, (UMHRI)","correspondingAuthor":false,"prefix":"","firstName":"George","middleName":"","lastName":"Kosteletos","suffix":""},{"id":304862354,"identity":"a7f3f465-8e2c-4ab4-bc63-c3ab96a03480","order_by":3,"name":"Orestis Giannakopoulos","email":"","orcid":"","institution":"First Department of Psychiatry, National and Kapodistrian University of Athens Medical School, Eginition Hospital","correspondingAuthor":false,"prefix":"","firstName":"Orestis","middleName":"","lastName":"Giannakopoulos","suffix":""},{"id":304862357,"identity":"35f8bba7-6aba-4989-804e-7ed69acb3248","order_by":4,"name":"Vaios Ziogas","email":"","orcid":"","institution":"CPHT, CNRS, École polytechnique, Institut Polytechnique de Paris","correspondingAuthor":false,"prefix":"","firstName":"Vaios","middleName":"","lastName":"Ziogas","suffix":""},{"id":304862358,"identity":"1d8ed495-dffb-4789-9212-351f362ffa9e","order_by":5,"name":"Panos C. Papageorgiou","email":"","orcid":"","institution":"Department of Electrical and Computer Engineering, University of Patras","correspondingAuthor":false,"prefix":"","firstName":"Panos","middleName":"C.","lastName":"Papageorgiou","suffix":""},{"id":304862362,"identity":"e07b696d-45c4-410a-8a81-8caea190223f","order_by":6,"name":"Georgia Vassiliou","email":"","orcid":"","institution":"University Mental Health, Neurosciences and Precision Medicine Research Institute “COSTAS STEFANIS”, (UMHRI)","correspondingAuthor":false,"prefix":"","firstName":"Georgia","middleName":"","lastName":"Vassiliou","suffix":""},{"id":304862363,"identity":"927e7899-5a5b-4602-aeb4-ce17e513e55d","order_by":7,"name":"Charalabos Papageorgiou","email":"","orcid":"","institution":"University Mental Health, Neurosciences and Precision Medicine Research Institute “COSTAS STEFANIS”, (UMHRI)","correspondingAuthor":false,"prefix":"","firstName":"Charalabos","middleName":"","lastName":"Papageorgiou","suffix":""},{"id":304862370,"identity":"eafb7816-e377-4661-b222-4f6de81fb4aa","order_by":8,"name":"Ioannis Boletis","email":"","orcid":"","institution":"Clinic of Nephrology and Renal Transplantation, Laiko General Hospital, Medical School, National and Kapodistrian University of Athens","correspondingAuthor":false,"prefix":"","firstName":"Ioannis","middleName":"","lastName":"Boletis","suffix":""}],"badges":[],"createdAt":"2024-04-29 09:23:19","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4341728/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4341728/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":57444600,"identity":"956aa241-53b4-4dd7-8751-bf48e5a6c355","added_by":"auto","created_at":"2024-05-30 18:59:29","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":79190,"visible":true,"origin":"","legend":"\u003cp\u003eReaction times and cooperative behaviour in the Prisoner’s Dilemma, separately for kidney donor (green) and transplant candidates (red). \u003cstrong\u003ea \u003c/strong\u003eAverage reaction times over participants in each strategy. \u003cstrong\u003eb \u003c/strong\u003eAverage reaction times through time by averaging over 10 consecutive trials (e.g., xaxis “10” designates the average reaction time over the first 10 trials, “20” over trials 10-20, etc.). \u003cstrong\u003ec \u003c/strong\u003eAverage percentage of cooperative responses over participants in each strategy. Error bars indicate ±1 \u003cem\u003eSEM\u003c/em\u003e. \u003cem\u003e*p\u003c/em\u003e \u0026lt; .1. \u003cem\u003e***p\u003c/em\u003e \u0026lt; .001 (gray is uncorrected).\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-4341728/v1/312da633dee9d4f051a8dabe.png"},{"id":57443465,"identity":"2dfceae5-ca8c-44be-a062-6bbbb0e87f1c","added_by":"auto","created_at":"2024-05-30 18:51:29","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":121106,"visible":true,"origin":"","legend":"\u003cp\u003eReaction times and cooperative behaviour in the Prisoner’s Dilemma, separately for kidney donor (green) and transplant candidates (red), following perceived “reward” (i.e. two consecutive trials in the first of which the participant cooperated and the second of which the PC cooperated) and following perceived “punishment” (i.e. two consecutive trials in the first of which the participant defected and the second of which the PC defected). \u003cstrong\u003ea \u003c/strong\u003eLeft: Average reaction times following reward and punishment. Right: Average percentage of cooperative responses following reward and punishment. \u003cstrong\u003eb \u003c/strong\u003eSpearman’s \u003cem\u003erho \u003c/em\u003ecorrelations between reaction times for punishment and reward for donors (left) and recipients (right). \u003cstrong\u003ec\u003c/strong\u003e Spearman’s \u003cem\u003erho \u003c/em\u003ecorrelations between percentage of cooperative responses for punishment and reward for recipients.\u003cstrong\u003e d\u003c/strong\u003e Spearman’s \u003cem\u003erho \u003c/em\u003ecorrelations between percentage of cooperative responses and reaction times for reward (left) and between percentage of cooperative responses and reaction times for punishment (right) for recipients. Error bars indicate ±1 \u003cem\u003eSEM\u003c/em\u003e. \u003cem\u003e***p\u003c/em\u003e \u0026lt; .001.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-4341728/v1/5fe4d9054527cd1be67eed5e.png"},{"id":63242792,"identity":"60bf9bbc-d7b3-4b50-a53c-e190d6311b4c","added_by":"auto","created_at":"2024-08-26 05:07:36","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":606384,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4341728/v1/c5488b19-51c5-4dee-ab83-3f16768bf271.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Cooperative behaviour in kidney donors and transplant candidates on the Prisoner’s Dilemma task","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eCooperation is an unselfish expression of the human social nature, although it can be also achieved between selfish but rational agents who might recognize mutual benefits due to the possibility of reciprocity [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. It indicates refraining from a higher individual benefit to achieve a collective benefit, which however requires to be reciprocated [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Previous studies have shown that reciprocity is also required for sustained cooperative behavior among humans and other animals [\u003cspan additionalcitationids=\"CR5\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Living donor kidney transplant is the optimal treatment for most patients with end-stage kidney disease. Data show that donors act like gift givers, donating voluntarily for altruistic reasons to help restore the health of a loved one [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Prospective organ recipients are concerned about the health and wellbeing of the donor candidate and find the offer emotionally burdensome [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Organ recipients usually feel unduly indebted thus expressing gratitude to the donor as a form of reciprocation [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Organ donation might thus be considered an example of high-cost cooperation [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. However, little is known regarding cooperation in kidney donor and transplant candidates outside the organ transplantation setting. Do kidney donors exhibit more cooperative behaviour than transplant recipients? Is behaviour affected by the strategy followed by their partner? How is cooperation influenced by the perception of reward or punishment? The present study investigated cooperative behaviour in kidney donor and transplant candidates using a computerized version of a standard moral dilemma task, the Iterated Prisoner\u0026rsquo;s Dilemma.\u003c/p\u003e \u003cp\u003eThe Prisoner\u0026rsquo;s Dilemma (PD) task traditionally refers to a situation in which two people suspected of committing a crime are questioned independently to admit or deny guilt for the crime [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. If both deny guilt, they can minimize jail time (higher reward), but, if both admit guilt, they will serve jail time (lower reward). If they do not respond the same way, one will serve far more jail time, while the other will be set free. Notably, choices in the PD are usually associated with cooperative and competitive intentions [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. For instance, making mutually beneficial choices shows an intention to maximize the reward of both players by sacrificing the highest personal reward [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. On the other hand, making self-interested decisions creates competitiveness and a goal to outperform the other player [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. In case of many PD iterations, players get information about the other partner\u0026rsquo;s intentions as the iterations evolve over time [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. The PD has been widely used to study the relationship between cooperation and several personality and psychological aspects, such as personality traits [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e], empathy [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e], and traits of psychopathy [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e], borderline personality and bipolar disorder [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e] and depression [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. The dynamics of cooperation are seen as relying on decision-making, feedback appraisal, perspective-taking and judgement for the return-benefits it bears for the agent [\u003cspan additionalcitationids=\"CR22\" citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eOur goal here was to study how cooperation differs between kidney donors and transplant candidates, and how their perception of reward or punishment by the other person affected their behaviour. The current study extends past research by implementing a computerized PD game in which participants who are either kidney donor or transplant candidates play a number of PD iterations with the computer as their partner. As mentioned earlier, cooperation requires trust in reciprocation [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e], PD thus constitutes a suitable tool to create a conflict by manipulating someone\u0026rsquo;s willingness to cooperate. Furthermore, the computer was programmed to follow different strategies thus offering better control of the conditions to which participants were exposed. More specifically, there were blocks of five different strategies: 1) Pavlov (the computer keeps the same move when winning and switches when losing), 2) Always cooperate (the computer cooperates in every trial), 3) Pavlov random (random moves were introduced in previous strategy), 4) Always defect (the computer defects in every trial), and 5) Tit-for-tat (the computer reciprocates the participant\u0026rsquo;s exact move). Notably, participants were unaware of the fact that the computer was programmed according to these strategies. We recorded participants\u0026rsquo; responses and reaction times throughout the task. To explore how reward and punishment affects behaviour, we identified \u0026ldquo;reward trials\u0026rdquo; as trials following two consecutive trials in the first of which the participant cooperated and the second of which the computer cooperated (i.e. the participant might have perceived the computer\u0026rsquo;s cooperation as a reward after the participant\u0026rsquo;s cooperation). We also identified \u0026ldquo;punishment trials\u0026rdquo; as trials following two consecutive trials in the first of which the participant defected and the second of which the computer defected (i.e. the participant might have perceived the computer\u0026rsquo;s defect as punishment due to their own previous defect).\u003c/p\u003e \u003cp\u003eWith regard to our hypotheses, we expected that both kidney donor and transplant candidates would cooperate more during reciprocating (pavlov, always cooperate, tit-for-tat) than during selfish strategies (pavlov random, always defect), due to the effect of the partner\u0026rsquo;s intention on cooperative behaviour. Similarly, we expected higher degree of cooperation following perceived reward than punishment. Our main question was whether compared to transplant recipients, kidney donors would show greater or equal degree of cooperation. On the other hand, we could argue that kidney donors would be more cooperative in PD, potentially reflective of a more general incline towards altruism and collective benefit outside the realm of organ donation. However, it is known that the motivation between organ donation is linked to empathy and compassion (e.g. in the case of familial donation: [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]). As donors seem to be driven by emotions, it is also possible that they would show an equal degree of cooperation in PD, due to the absence of emotional context or loved person that needs their help.\u003c/p\u003e"},{"header":"2. Materials and Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1. Participants\u003c/h2\u003e \u003cp\u003eForty-eight adults (18 female) aged between 21 and 70 years old (\u003cem\u003eM\u003c/em\u003e\u0026thinsp;\u0026plusmn;\u0026thinsp;\u003cem\u003eSD\u003c/em\u003e age of 48.76\u0026thinsp;\u0026plusmn;\u0026thinsp;13.02 years) participated in the experiment, of whom 21 were kidney donor candidates and 27 were kidney transplant candidates. Donors were aged 53.00\u0026thinsp;\u0026plusmn;\u0026thinsp;8.97 and recipients were aged 45.52\u0026thinsp;\u0026plusmn;\u0026thinsp;14.81. Age was not significantly different between groups (\u003cem\u003et\u003c/em\u003e(35)\u0026thinsp;=\u0026thinsp;1.78, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.084). Biological gender was not balanced between groups, as there were 15 female donors, but only 3 female recipients. According to inclusion criteria, subjects needed to be primary education graduates and have a decent understanding of Greek language. Prior to participation, all subjects were interviewed by a psychiatrist in order to exclude the presence of any major clinical psychopathology or cognitive decline. The inclusion criteria were based on the assumption that the iterated procedure of the PD implies that every participant has the ability to perform logically consistent reasoning, associated with the optimization of one\u0026rsquo;s reward [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. The study was performed in the psychophysiology laboratory of the First Department of Psychiatry, \u0026ldquo;Eginition Hospital\u0026rdquo;, National and Kapodistrian University of Athens, Medical School, Greece in collaboration with the Department of Nephrology and Renal Transplantation, \u0026ldquo;Laikon\u0026rdquo; Hospital, National and Kapodistrian University of Athens, Medical School, Greece. The study was approved by the local ethics committee (Number: 653, 7/11/2019). The experiment was performed in accordance with relevant guidelines and regulations. All participants were extensively informed about the procedure and gave written consent for participation.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.2. Prisoner\u0026rsquo;s dilemma\u003c/h2\u003e \u003cp\u003eThe Prisoner\u0026rsquo;s Dilemma (PD), first introduced by the mathematicians Melvin Flood and Melvin Dresher and given its final form and name by Albert W. Tucker, comprises a tool to study cooperation and defection [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. Traditionally, participants are presented the following scenario: \u0026ldquo;Two prisoners, A and B, suspected of committing a robbery together, are isolated and urged to confess. Each is concerned only with getting the shortest possible prison sentence for himself; each must decide whether to confess without knowing his partner\u0026rsquo;s decision. Both prisoners, however, know the consequences of their decisions: 1) if both confess, both go to jail for five years; 2) if neither confesses, both go to jail for one year (for carrying concealed weapons); and 3) if one confesses while the other does not, the confessor goes free (for turning state\u0026rsquo;s evidence) and the silent one goes to jail for 20 years.\u0026rdquo;\u003c/p\u003e \u003cp\u003eHere, we used a computerized version of the Iterative PD. The game was played between a participant and a computer (PC). Participants were exposed to the dilemma on several successive rounds (trials), and were required to select between two options: \u0026ldquo;cooperate\u0026rdquo; (protect their partner) or \u0026ldquo;defect\u0026rdquo; (testify against their partner). Thus, there are four possible combinations of choices on behalf of the two protagonists (participant-PC), depending on which some points are given: 1) Cooperate-Cooperate (3 points), 2) Defect-Defect (1 point), 3) Cooperate-Defect (0 points), and 4) Defect-Cooperate (5 points). In each trial, the dilemma is set again and both the participant and the PC make a simultaneous move. After the moves have been made, the participant is presented with their own and the PC\u0026rsquo;s score of that trial, their own and the PC\u0026rsquo;s cumulative score over all trials so far, their own and the PC\u0026rsquo;s choice at that trial, and the pay-off matrix. The pay-off matrix is a 2-by-2 matrix, whose rows are labelled by the participants\u0026rsquo; options \u0026ldquo;Cooperate\u0026rdquo; or \u0026ldquo;Defect\u0026rdquo; and its columns by the PC\u0026rsquo;s options. Each element of the matrix consists of the pair of points that the participant and the PC will receive in the corresponding case.\u003c/p\u003e \u003cp\u003eThe PD task constituted of 5 blocks of 25 trials each. Each block followed one of five strategies: 1) Pavlov (the computer keeps the same move when winning and switches when losing), 2) Always cooperate (the computer cooperates in every trial), 3) Pavlov random (random moves were introduced in previous strategy), 4) Always defect (the computer defects in every trial), and 5) Tit-for-tat (the computer reciprocates the participant\u0026rsquo;s exact move). The order of the strategy blocks was randomized across participants. Finally, participants were not aware how many trials or blocks the experiment was comprised of, in order to avoid the end-game effect [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e2.3. Data analysis\u003c/h2\u003e \u003cp\u003eBecause the participants were not prompted for the change of strategy every 25 trials, the first 3 trials of each strategy were excluded from all analyses, as it was improbable that participants could notice the change of strategy already.\u003c/p\u003e \u003cp\u003e \u003cem\u003eReaction times and cooperation.\u003c/em\u003e First, we wanted to investigate potential differences in reaction times and cooperation between donors and recipients. Reaction times were averaged over trials. Cooperation was computed as the percentage of trials participants showed cooperative behaviour. Two 2 \u003cem\u003e(group: donors, recipients)\u003c/em\u003e x 5 \u003cem\u003e(strategy: Pavlov, Always cooperate, Pavlov random, Always defect, Tit-for-tat)\u003c/em\u003e repeated measures ANOVAs were conducted separately for reaction times and cooperation.\u003c/p\u003e \u003cp\u003e \u003cem\u003eReaction times and cooperation in reward and punishment.\u003c/em\u003e We investigated how task performance differed in response to perceived reward and punishment. \u0026ldquo;Reward trials\u0026rdquo; were considered those following two consecutive trials in the first of which the participant cooperated and the second of which the computer cooperated, whereas \u0026ldquo;punishment trials\u0026rdquo; were those following two consecutive trials in the first of which the participant defected and the second of which the computer defected. Two 2 \u003cem\u003e(group: donors, recipients)\u003c/em\u003e x 2 \u003cem\u003e(condition: reward, punishment)\u003c/em\u003e repeated measures ANOVAs were performed on reaction times and cooperation, separately. Furthermore, Spearman\u0026rsquo;s \u003cem\u003erho\u003c/em\u003e correlations were tested between reaction times for punishment and reward, and between percentage of cooperative responses for punishment and reward, separately for donors and recipients.\u003c/p\u003e \u003c/div\u003e"},{"header":"3. Results","content":"\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003e3.1. Reaction times and cooperation in the Prisoner\u0026rsquo;s Dilemma\u003c/h2\u003e \u003cp\u003eA 2 x 5 repeated measures ANOVA with group and strategy as independent variables revealed no significant main effect or interaction between the variables (strategy: \u003cem\u003eF\u003c/em\u003e(4,184)\u0026thinsp;=\u0026thinsp;1.15, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.34; group: \u003cem\u003eF\u003c/em\u003e(1,46)\u0026thinsp;=\u0026thinsp;.72, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.40; strategy X group: \u003cem\u003eF\u003c/em\u003e(4,184)\u0026thinsp;=\u0026thinsp;1.71, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.15) (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eA). Throughout the course of the session (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eB), there was a trend for recipients to be slower than donors, but that was not significant (trials 20\u0026ndash;30: \u003cem\u003et\u003c/em\u003e(46) = -1.96, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.056).\u003c/p\u003e \u003cp\u003eAs expected, participants\u0026rsquo; degree of cooperation varied between strategies (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eC). This was confirmed by a repeated measures ANOVA showing a significant main effect of strategy (\u003cem\u003eF\u003c/em\u003e(4,184)\u0026thinsp;=\u0026thinsp;9.211, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;.001). Pairwise contrasts revealed that this was due to participants cooperating more in the Always cooperate condition compared to Always defect (\u003cem\u003et\u003c/em\u003e(47)\u0026thinsp;=\u0026thinsp;4.226, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;.001) and Tit for Tat (\u003cem\u003et\u003c/em\u003e(47)\u0026thinsp;=\u0026thinsp;4.381, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;.001), the Tit for Tat condition compared to Always defect (\u003cem\u003et\u003c/em\u003e(47)\u0026thinsp;=\u0026thinsp;3.092, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.003), the Pavlov compared to Always defect (\u003cem\u003et\u003c/em\u003e(47)\u0026thinsp;=\u0026thinsp;4.635, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;.001) and Random (\u003cem\u003et\u003c/em\u003e(47)\u0026thinsp;=\u0026thinsp;3.975, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;.001), and the Tit for Tat compared to Pavlov random (uncorrected \u003cem\u003ep\u003c/em\u003e; \u003cem\u003et\u003c/em\u003e(47)\u0026thinsp;=\u0026thinsp;2.638, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.011). There was no significant effect of group or interaction between the variables (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;.4).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003e3.2. Behaviour related to reward and punishment\u003c/h2\u003e \u003cp\u003eWe investigated how task performance differed in response to perceived reward and punishment. \u0026ldquo;Reward trials\u0026rdquo; were considered those following two consecutive trials in the first of which the participant cooperated and the second of which the PC cooperated, whereas \u0026ldquo;punishment trials\u0026rdquo; were those following two consecutive trials in the first of which the participant defected and the second of which the PC defected.\u003c/p\u003e \u003cp\u003eA 2 (donors, recipients) x 2 (reward, punishment) repeated measures ANOVA on reaction times showed no significant effect or interaction between the variables (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;.4) (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eA, left). A 2 (donors, recipients) x 2 (reward, punishment) repeated measures ANOVA on percentage of cooperation revealed a significant main effect of condition (\u003cem\u003eF\u003c/em\u003e(1,44)\u0026thinsp;=\u0026thinsp;73.805, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;.001). Pairwise contrasts showed that this was due to higher cooperation following reward than punishment (\u003cem\u003et\u003c/em\u003e(45)\u0026thinsp;=\u0026thinsp;8.778, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;.001). There was no significant effect of group or interaction between the variables (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;.9) (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eA, right).\u003c/p\u003e \u003cp\u003eFinally, we conducted Spearman\u0026rsquo;s \u003cem\u003erho\u003c/em\u003e correlations between reaction times and percentage of cooperative responses following reward vs. punishment. Results revealed significant positive correlations between reaction times for punishment and reaction times for reward in both groups (donors: \u003cem\u003erho\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.537, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.015; recipients: \u003cem\u003erho\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.554, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.003) (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eB). Furthermore, the higher the percentage of cooperation following reward, the lower the percentage of cooperation following punishment, but only for recipients (\u003cem\u003erho\u003c/em\u003e\u0026thinsp;=\u0026thinsp;\u0026minus;\u0026thinsp;.489, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.011) (donors: \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.4). For recipients, the more they cooperated, the faster they responded following reward (\u003cem\u003erho\u003c/em\u003e\u0026thinsp;=\u0026thinsp;\u0026minus;\u0026thinsp;.458, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.019) (donors: \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.6) (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eC), while the more they cooperated, the slower they responded following punishment (\u003cem\u003erho\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.603, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.001) (donors: \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.5) (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eD).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"4. Discussion","content":"\u003cp\u003eIn this study, we investigated cooperative behaviour in kidney donor and transplant candidates using a standard moral dilemma task, the Prisoner\u0026rsquo;s Dilemma (PD). The current study extends past research by implementing a computerized PD game in which participants who are either kidney donor or transplant candidates play a number of PD iterations with the computer as their partner. Τhe computer was programmed to follow different strategies which were more or less cooperative or conflicting. We analyzed reaction times and degree of cooperation following reward vs. punishment in kidney donor and transplant candidates. We answer our research questions by demonstrating the following key findings: 1) Confirming the effect of the partner\u0026rsquo;s intention, participants\u0026rsquo; degree of cooperation was modulated based on the strategy of the computer (higher/lower cooperation for more reciprocative/conflicting strategies), and was higher following reward than punishment; 2) There was a trend for donors to be faster than recipients, while in both groups reaction times following reward and punishment were correlated; and 3) Recipients responded equally strongly to reward and punishment as the higher the cooperation following reward, the lower the cooperation following punishment, which was also reflected in faster (slower) reaction times for reward (punishment), whereas donors did not show correlations between cooperation to reward and punishment. Overall, our findings contribute to the investigation of the psychological and cognitive features of kidney donors.\u003c/p\u003e \u003cp\u003eAs expected, participants\u0026rsquo; degree of cooperation was modulated based on the strategy of the computer, namely both kidney donor and transplant candidates similarly cooperated less during selfish behaviour. More specifically, we observed higher degree of cooperation for more reciprocative strategies, i.e. pavlov, always cooperate, tit-for-tat, whereas there was lower cooperation for conflicting strategies, i.e. pavlov random, always defect. This indicates that participants\u0026rsquo; willingness to cooperate with others changes as a function of the nature of their relationships, namely selfish treatment triggered retaliation. Previous studies have showed that older adults tend to handle emotion regulation in interpersonal conflict passively [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e] and behave assertively in situations that elicit anger or annoyance [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. The age distribution of our sample was above the younger adults who are usually considered until 25 years old. Therefore, our finding is in line with previous work showing that people, independently of their age, tend to adjust their cooperation levels based on the behaviour of their partner [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. Additionally, this is further corroborated by our other finding that cooperation degree was higher following reward compared to punishment. In particular, this provides evidence for two points: 1) the measures of \u0026ldquo;reward\u0026rdquo; and \u0026ldquo;punishment\u0026rdquo; that we constructed indeed represented the perception of participants and thus affected their subsequent decisions; and 2) it confirms the observation that cooperation is modulated by the perceived intention of the partner\u0026rsquo;s reciprocative or selfish behaviour [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. Our aforementioned findings did not significantly differ between groups, suggesting that cooperative performance in the PD is not affected by the process of kidney donation or receival. Future studies are needed to investigate whether kidney donor and transplant candidates are differentiated in other aspects of morally-laden behaviour, potentially using a different kind of task.\u003c/p\u003e \u003cp\u003eFurthermore, there was a trend for donors to be faster than recipients, which was however not statistically significant. First, it is possible that this did not reach significance due to the low sample size in our study. Further studies employing a larger sample size are needed to test this possibility. One explanation could lie on possible cognitive impairments of transplant candidates compared to kidney donors [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]. Indeed, cognitive impairment is common in patients undergoing hemodialysis [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]. The most affected domains are executive functions and speed of processing [\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e]. Another speculation could lie in an overall tendency of transplant candidates to be more suspicious and show less trust with regard to the motives of other individuals, which might have led them to take more time to make a decision that taps onto mutual trust and the relationship between the partners [\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e]. Additionally, we observed that in both groups reaction times following reward and punishment were correlated. This indicates that decision speed was not differentiated at the level of perceived reward or punishment by the other player/computer.\u003c/p\u003e \u003cp\u003eInterestingly, transplant recipients\u0026rsquo; behaviour was correlated between reward and punishment: the higher the degree of cooperation following reward, the lower the degree of cooperation following punishment. Furthermore, the more recipients cooperated following reward, the faster they responded, while the more they cooperated following punishment, the slower they responded. The transplant candidates\u0026rsquo; hesitancy to cooperate after punishment may be due to their increased sense of vulnerability [\u003cspan additionalcitationids=\"CR36\" citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e], leading to a higher level of depression and concerned stance (e.g. somatic concerns) compared to kidney donor candidates [\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e]. In this view, recipients\u0026rsquo; hesitancy to proceed with an altruistic choice lies on hesitancy to proceed with a course of action that will increase their vulnerability. On the contrary, kidney donors did not show correlations neither between the degree of cooperation following reward and punishment nor between the degree of cooperation and reaction times. We will provide alternative explanations for these results. First, it seems like transplant recipients might have a strong preference for reward together with a strong dislike for punishment. In addition, the observation that transplant recipients cooperated faster after reward, whereas they cooperated slower after punishment, indicates that it took more time for them to cooperate after punishment. This delay might be related to being less inclined to cooperate after punishment. Nevertheless, previous studies investigating decision-making in moral dilemmas have assumed that players think less to make intuitive decisions and longer to make deliberate decisions, and thus concluded that the type of decisions with smaller reaction times are intuitive and those with the longer reaction times are deliberate [\u003cspan additionalcitationids=\"CR40\" citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe absence of the aforementioned effects for kidney donor candidates shows that they were more decided to cooperate independently of whether their partner/computer rewarded or punished them. This is in line with the notion that organ donation resembles gift giving via the voluntary will to help someone for altruistic reasons [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. It is also interesting to highlight that numerous studies have shown that most organ donors make an instantaneous decision to donate with little or no deliberation and have no regrets about doing so [\u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e, \u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e43\u003c/span\u003e]. Another relevant point here refers to the personality characteristics of kidney donor candidates. Kidney donors have been observed to be higher in agreeableness and lower in neuroticism compared to the general population [\u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e44\u003c/span\u003e, \u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e45\u003c/span\u003e]. Agreeableness includes cooperativeness and a prosocial, forgiving orientation, while low neuroticism is linked to emotional stability and low vulnerability to stress. People with these characteristics might be more willing to donate, as agreeableness and neuroticism play an important role in social contexts [\u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e44\u003c/span\u003e]. Another possibility could be that donors\u0026rsquo; altruistic behaviour was a reflection of social desirability, which potentially underlines their decision for organ donation [\u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e46\u003c/span\u003e, \u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e47\u003c/span\u003e]. Therefore, our findings provide evidence that donors are more decisive during decision-making on dilemmas with regard to cooperation vs. competition, whereas recipients show a dependence on their partner\u0026rsquo;s behaviour, as they cooperate more when their partner rewards them, but cooperate less when their partner punishes them. Future studies are needed to directly investigate potential associations between personality and cooperation in the prisoner\u0026rsquo;s dilemma in organ donors and recipients. Overall, we believe that our findings shed light on the psychological and cognitive characteristics of kidney donors, which is fundamental to the optimization of their psycho-social management and support [\u003cspan additionalcitationids=\"CR49\" citationid=\"CR48\" class=\"CitationRef\"\u003e48\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e50\u003c/span\u003e]. Crucially, this issue has clear moral implications linked to the principles of autonomy and justice [\u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e51\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eOur study is not without limitations. First, biological sex was not balanced between groups, with the majority of donors being females whereas recipients being mostly males. Indeed, previous work has revealed a gender disparity in living renal transplant donation, namely that the vast majority of donors are females, which might be related to social desirability stemming from societal pressure [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR52\" class=\"CitationRef\"\u003e52\u003c/span\u003e], although not all research converges to this hypothesis [\u003cspan citationid=\"CR53\" class=\"CitationRef\"\u003e53\u003c/span\u003e]. Second, our sample size was limited which means we might have not have been able to detect smaller effect sizes. Third, a healthy group not involved in the kidney transplant procedure would be necessary to serve as a control, in order to test whether the effects identified in the kidney donor and transplant candidates would also be present in a sample of healthy adults. This would be especially useful for strengthening the findings on differences between groups with regard to reward and punishment.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003ch2\u003eCompeting interests\u003c/h2\u003e \u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eFunding\u003c/h2\u003e \u003cp\u003e The study was funded by the Regional Governor of Attica and co-funded by the Athanasios and Marina Matinou Foundation (AMMF) \u0026ndash; a non-profit civil company \u0026lsquo;AEGEAS\u0026rsquo;.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eI.Z.: participated in data analysis, participated in the writing of the paper; S.T.: participated in data analysis, participated in the writing of the paper; G.K.: participated in research design, contributed new reagents or analytic tools, participated in the writing of the paper; O.G.: participated in research design, participated in the performance of the research; V.Z.: participated in data analysis, participated in the writing of the paper; P.C.P.: participated in research design, participated in the writing of the paper; G.V.: participated in research design, participated in the performance of the research, contributed new reagents or analytic tools; C.P.: participated in research design, contributed new reagents or analytic tools, participated in the writing of the paper; I.B.: participated in research design, participated in the writing of the paper, provided access to participants.\u003c/p\u003e\u003ch2\u003eAcknowledgement\u003c/h2\u003e\u003cp\u003eWe would like to thank the patients and kidney donors for taking part in the study.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eThe datasets generated during and analysed during the current study are available from the corresponding author on reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eCurry, O. 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Clinical transplantation 21, 314\u0026ndash;320 (2007).\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Prisoner’s Dilemma, kidney transplant, kidney donor, cooperation, moral behaviour.","lastPublishedDoi":"10.21203/rs.3.rs-4341728/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4341728/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eInterpersonal cooperation is a prerequisite for individual and social well-being, while organ donation has a plethora of moral implications beyond its medical relevance. However, little has been known about whether kidney donors exhibit higher cooperation in morally-laden decisions. Our study aims to fill this gap by comparing cooperation in kidney donors vs. transplant candidates using a computerized Prisoner\u0026rsquo;s Dilemma task. Participants were presented with dilemmas and were required to cooperate with or defect against a fictional partner (computer). Participants\u0026rsquo; degree of cooperation was modulated based on the computer\u0026rsquo; strategy (higher/lower cooperation for more reciprocative/conflicting strategies). There was a trend for donors to be faster than transplant candidates. Interestingly, the higher the degree of cooperation following reward, the lower the degree of cooperation following punishment for transplant candidates. The latter were faster when cooperating after reward, but slower when cooperating after punishment. Our findings provide evidence that kidney donors are more decisive with regard to cooperation vs. competition. On the contrary, transplant candidates show a stronger dependence on their partner\u0026rsquo;s behaviour. Overall, our results suggest that cooperative behaviour differs between kidney donors and transplant candidates, and that the Prisoner\u0026rsquo;s Dilemma task could provide a suitable tool to study those patterns.\u003c/p\u003e","manuscriptTitle":"Cooperative behaviour in kidney donors and transplant candidates on the Prisoner’s Dilemma task","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-05-30 18:51:25","doi":"10.21203/rs.3.rs-4341728/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"96bed509-fab7-4bea-9eaf-999babcd27d2","owner":[],"postedDate":"May 30th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":32185684,"name":"Biological sciences/Psychology/Human behaviour"},{"id":32185685,"name":"Health sciences/Diseases/Kidney diseases/Chronic kidney disease"}],"tags":[],"updatedAt":"2024-08-26T04:59:30+00:00","versionOfRecord":[],"versionCreatedAt":"2024-05-30 18:51:25","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4341728","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4341728","identity":"rs-4341728","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}