Neurobiological Underpinnings of Identity Formation in Adolescence. In W. H. J. Meeus (chair, invited symposium), Advances in the study of adolescent identity formation. Symposium conducted at the 18th European Conference on Developmental Psychology (ECDP), Utrecht, The Netherlands

Aim: Adolescence is a key period for the development of a clear identity (Erikson, 1968). Researchers have argued that establishing a clear identity requires at least two processes: Information seeking behavior to explore identity alternatives (Berzonsky, 1989), and goal-directed behavior, for example to pursue long-term academic goals (Burrow & Hill, 2011). Parallel to adolescents’ search for identity, massive changes in brain structure and morphology in brain regions occur that are crucially involved in information seeking behavior and goal-directed behavior (Mills & Tamnes, 2014). For instance, structural changes in the prefrontal cortex (PFC) have been linked to information seeking behavior. Moreover, subcortical brain regions, especially the Nucleus accumbens (NAcc) have been related to goal-orientation and motivated behavior. However, it remains unknown how neurological processes accompanying changes in information seeking and motivation predict identity over time. Therefore, the aim of this multi-method multi sample longitudinal study was to investigate how behavioral changes in goal-directed behavior (Study 1 and Study 2) and structural changes in PFC and NAcc gray matter volume (Study 2) predicted identity formation. Method: 497 adolescents (Study 1; Mage 13.03 at T1) and 138 adolescents (Study 2; Mage 14.69 at T1) were followed across three biannual waves. Identity was assessed at wave four. Results: Latent growth curve models revealed that across Study 1 and Study 2 more self-reported goal-directed behavior across three waves predicted stronger identity commitments, less reconsideration of commitments and more in-depth exploration of commitments at wave four. Study 2 revealed that higher NAcc volume predicted stronger identity commitments and less reconsideration of commitments. Moreover, higher initial PFC volume as well as less strongly decreasing PFC volume predicted more in-depth exploration. Conclusion: Our findings supported the importance of goal-directed behavior in identity formation over time across two studies. Moreover, we identified neurobiological markers predicting adolescents’ identity formation.