Interactions of sex and stress in modulation of ventral tegmental area dopaminergic activity

Dopaminergic (DA) neurons of the ventral tegmental area (VTA) have long been studied for their role in reward prediction and goal-directed behaviors. However, appreciation is growing for a complementary role of VTA DA neurons in responding to aversive stimuli and as critical substrates for behavioral sequelae of stressful experiences. As is the case across neuroscience, the majority of our knowledge about VTA DA neurons comes from studies in male subjects. Recent years have seen an increase in the inclusion of female subjects and exploration of sex differences. There is now an emerging body of literature showing that although there are minimal basal structural and functional sex differences in VTA DA neurons, experience-dependent changes in these neurons can differ significantly between males and females. Here, we discuss the potential implications of sex differences in VTA function and review recent data on sex differences and similarities of DA neurons at baseline and following stress.