Figure 7.

Schematic diagram of adolescent changes in VS-induced Fos responses (indicated by shading). VS activated the posterior medial amygdala and paranigral VTA neurons similarly in juvenile and adult male hamsters, but activated non-dopaminergic interfascicular and parabrachial VTA neurons, nucleus accumbens core, and infralimbic medial prefrontal cortex only in adults (bold outline). This pattern of selective neural activation in adulthood correlates with the ability of VS to serve as an unconditioned stimulus for reward in adult, but not juvenile males, indicating recruitment of these specific cell groups in the adolescent development of social reward.