Adolescent gender differences in neural reactivity to a friend's positive affect and real-world positive experiences in social contexts

Abstract

Peers become increasingly important during adolescence, with emerging gender differences in peer relationships associated with distinct behavioral and emotional outcomes. Males tend to socialize in larger peer groups with competitive interactions, whereas females engage in longer bouts of dyadic interaction with more intimacy. To examine gender differences in neural response to ecologically valid displays of positive affect and future social interactions, 52 adolescents (14-18 years old; female = 30) completed a social reward functional magnetic resonance imaging (fMRI) task with videos of a same-gender best friend (BF) or unfamiliar peer (UP) expressing positive (versus neutral) affect. Participants completed ecological momentary assessment of social experiences for two 5-day intervals. Compared with females, males more often reported that their happiest experience in the past hour occurred with class/teammates. Females and males displayed greater fusiform gyrus (FG) activation during BF and UP conditions, respectively (p_voxel<0.0001, p_cluster<0.05, family-wise error). Compared with males, females exhibited greater nucleus accumbens (NAcc)-precuneus functional connectivity to BF Positive> UP Positive. An exploratory analysis indicated that the association of male gender with a greater proportion of positive experiences with class/teammates was statistically mediated by greater NAcc-precuneus functional connectivity. Gender differences in positive social experiences may be associated with reward and social cognition networks.

Keywords: Adolescence; Ecological momentary assessment; Face processing; Functional magnetic resonance imaging; Gender differences; Social reward.

Fig. 1

The Best Friend Task. Colors denote type of stimuli presented during each block (20 s). BF = best friend; UP = unfamiliar peer.

Fig. 2

Gender-by-Familiarity Effect. Males displayed greater activation of bilateral fusiform gyrus and extrastriate cortex than females when viewing an unfamiliar peer (UP), regardless of stimuli valence. Females displayed greater activation these brain regions during Best Friend (BF) versus UP conditions, whereas males did not differentiate between conditions, with the exception of right fusiform gyrus in the opposite direction (UP > BF).

Fig. 3

Mediation Analysis. Nucleus accumbens functional connectivity with precuneus during Best Friend-Positive > Unfamiliar Peer-Positive conditions, which was significantly higher in females than males, mediated gender differences in the proportion of positive experiences with class/teammates.