Transduction of socio-environmental influences into functional genomic responses is mediated by the brain’s perception of social conditions, and its subsequent regulation of hormones, neurotransmitters, and other signaling molecules that disseminate throughout the body to activate cellular receptors and transcription factors. For example, the sympathetic nervous system (SNS) and the hypothalamic-pituitary-adrenal (HPA) axis represent two major pathways by which central nervous system (CNS) perceptions of negative social conditions can regulate gene transcription in a wide array of somatic cells (Sapolsky, 1994). Positive psychological states may also regulate human gene expression (Dusek et al., 2008), although their molecular mediators are less well understood.
