Neural similarity in nucleus accumbens during decision‐making for the self and a best friend: Links to adolescents' self‐reported susceptibility to peer influence and risk taking

• Published in: Human brain mapping 2023-07, Vol.44 (10), p.3972-3985
• Main Authors: Dai, Junqiang, Kwon, Seh‐Joo, Prinstein, Mitchell J., Telzer, Eva H., Lindquist, Kristen A.
• Format: Article
• Language: English
• Subjects: Adolescent; Adolescent Behavior; Adolescents; Child; Decision analysis; Decision making; Friends; Humans; individual difference; Medical imaging; Neuroimaging; Nucleus accumbens; Nucleus Accumbens - diagnostic imaging; Peer Influence; Peer relationships; Prefrontal cortex; representational similarity analysis (RSA); Risk; Risk taking; Self Report; Similarity; Susceptibility; Teenagers
• ISSN: 1065-9471; 1097-0193
• DOI: 10.1002/hbm.26317

Adolescence is marked by increased peer influence on risk taking; however, recent literature suggests enormous individual variation in peer influence susceptibility to risk‐taking behaviors. The current study uses representation similarity analysis to test whether neural similarity between decision‐making for self and peers (i.e., best friends) in a risky context is associated with individual differences in self‐reported peer influence susceptibility and risky behaviors in adolescents. Adolescent participants (N = 166, Mage = 12.89) completed a neuroimaging task in which they made risky decisions to receive rewards for themselves, their best friend, and their parents. Adolescent participants self‐reported peer influence susceptibility and engagement in risk‐taking behaviors. We found that adolescents with greater similarity in nucleus accumbens (NACC) response patterns between the self and their best friend reported greater susceptibility to peer influence and increased risk‐taking behaviors. However, neural similarity in ventromedial prefrontal cortex (vmPFC) was not significantly associated with adolescents' peer influence susceptibility and risk‐taking behaviors. Further, when examining neural similarity between adolescents' self and their parent in the NACC and vmPFC, we did not find links to peer influence susceptibility and risk‐taking behaviors. Together, our results suggest that greater similarity for self and friend in the NACC is associated with individual differences in adolescents' peer influence susceptibility and risk‐taking behaviors. This research found that adolescents with greater similarity in nucleus accumbens response patterns when making decisions for themselves and a best friend reported greater susceptibility to peer influences and increased risk‐taking behaviors in daily life. Our result suggests that greater neural similarity for the self and peers in the reward system may index peer influence susceptibility and risk‐taking behaviors during adolescence. This study may provide valuable information for identifying at‐risk youths and shed light on future prevention and intervention programs.