The role of intersubjective and intrapersonal traits in the sociality of healthy young adults

Self-other relationship is a fundamental component in shaping an individual’s mind and health. Two principal components of self-other relationship can be distinguished. Intersubjectivity comprises empathy and other relational phenomena, whereas subjectivity includes an intrapersonal sense of agency and identity. In this study, we aim to evaluate how individual differences in both intrapersonal and intersubjective traits influence the quality of friendship and the experience of loneliness. We hypothesize that the quality of friendships and the experience of loneliness arise not only from interpersonal factors, but also from distinct intrapersonal features of the individual. We administered a set of psychometric questionnaires to a random sample of non-clinical, young adults. Outcome variables concerned personal experiences of friendship and loneliness. Factor analysis was employed to confirm the duality of latent intrapersonal and intersubjective factors. The results confirmed that the intrapersonal factor has an important influence on the sociability of healthy young adults, independent of intersubjective factors and lockdown-related changes due to the COVID-19 pandemic. A low sense of agency together with high psychotic-like experiences and schizotypal traits strongly predicted less friendships and more loneliness. A mediation analysis further showed that the effect of intrapersonal traits on loneliness was partially mediated by the participants’ friendships. Our results emphasize a central role of self-concept for social life quality. These findings further provide a new perspective for individuals in the general population with low social life quality and possible subclinical alterations of self-experience. Finally, our study also brings potential contributions to the prevention, treatment, and rehabilitation strategies for psychopathological conditions associated with both self-disturbances and social deficits.