The Neurobiology and Genetics of Affiliation and Social Bonding in Animal Models
Affiliation and social attachments in some form are critical for the survival of all mammalian species and significantly influence human mental health. Although very little is known regarding the underlying neurobiological mechanisms influencing the development of human relationships, studies using animal models have gained insights into the regulation of this process in other species. In this chapter we will discuss several animal models that have been particularly useful for investigating the neural and genetic mechanisms modulating affiliation and social attachment. We focus on a core set of signaling systems that modulate perception of social cues, social memory, motivation, and reward. The contribution of genetics will be reviewed where information is available. Specifically, we outline the role that oxytocin and vasopressin systems play in modulating social recognition memory, as well as the interactions of dopamine and endogenous opioids on social motivation and reward. The parallel actions of these neuromodulators represent a highly conserved, socially directed motivational system underlying multiple forms of social attachment, including mother infant interactions and adult pair bonds. A better understanding of these systems has the potential to provide insights into complex human social relationships. It may also pave the way for novel therapeutics to treat the sociobehavioral deficits associated with autism and other disorders.