Learning whom not to trust across early and middle adolescence: A longitudinal neuroimaging study to trusting behavior involving an uncooperative other.

Longitudinal changes in trusting behavior across adolescence and their neural correlates were examined. Neural regions of interest (ROIs) included the medial prefrontal cortex (mPFC), dorsal anterior cingulate cortex (dACC), left anterior insula (AI), bilateral ventral striatum (VS), and right dorsal striatum (DS). Participants (wave 1 age: M = 12.90) played the investor in a Trust Game with an uncooperative trustee three times (1-year interval). Analyses included 77 primarily Dutch participants (33 females). Participants decreased their investments with wave. Furthermore, activity was heightened in mPFC, dACC, and DS during investment and repayment, and in right VS (investment) and AI (repayment). Finally, DS activity during repayment increased with wave. These findings highlight early-middle adolescence as an important period for developing sensitivity to uncooperative behavior.

The development of adolescent trust behavior.

Interpersonal trust shows developmental changes during adolescence. The current study used a longitudinal design to examine the development of trust behavior, the presence of gender differences in these developmental trajectories, and the association between individual differences in these developmental trajectories and perspective-taking abilities. The participants played a trust game with a hypothetical trustworthy partner and a trust game with a hypothetical untrustworthy partner in 3 consecutive years (Mage = 12.55 years, Mage = 13.54 years, and Mage = 14.54 years). Concerning the development of trust behavior, the results showed an age-related increase in initial trust behavior and indicated increasingly adaptive trust behavior with age during untrustworthy interactions, whereas no evidence was found for age-related changes in the adaptation of trust during trustworthy interactions. Gender differences were found for the development of initial trust behavior (with boys showing a stronger increase with age than girls), whereas no support was found for the presence of gender differences in the developmental trajectories of adaptive trust behavior during trustworthy and untrustworthy interactions. Furthermore, no evidence was found for perspective-taking abilities to explain individual differences in the development of initial trust behavior or in the development of adaptive trust behavior during trustworthy and untrustworthy interactions. The results provide evidence that, during adolescence initial trust behavior increased with age, more for boys than for girls, and that both boys and girls showed a stronger adaptive response to the untrustworthy partner but not to the trustworthy partner.

The effect of incorrect prior information on trust behavior in adolescents.

During adolescence, social cognition and the brain undergo major developments. Social interactions become more important, and adolescents must learn that not everyone can be trusted equally. Prior knowledge about the trustworthiness of an interaction partner may affect adolescents' expectations about the partner. However, the expectations based on prior knowledge can turn out to be incorrect, causing the need to respond adaptively during the interaction. In the current fMRI study, we investigated the effect of incorrect prior knowledge on adolescent trust behavior and on the neural processes of trust. Thirty-three adolescents (Mage = 17.2 years, SDage = 0.5 years) played two trust games with partners whose behavior was preprogrammed using an algorithm that modeled trustworthy behavior. Prior to the start of both games, participants received information suggesting that the partner in one game was untrustworthy (raising incorrect expectations) and the partner in the other game trustworthy (raising correct expectations). Results indicated that participants adapted their trust behavior following incorrect prior expectations. No evidence for a change in trust behavior was shown when prior expectations were correct. fMRI analyses revealed that when receiving the partner's response, activity in the dorsolateral prefrontal cortex and in the superior parietal gyrus were increased when participants had incorrect expectations about the partner compared to when participants had correct expectations. When making trust decisions, no significant differences in neural activity were found when comparing the two games. This study provides insight into how adolescent trust behavior and neural mechanisms are affected by expectations and provides an increased understanding of the factors that influence adolescent social interactions.