Serotonergic regulation of social function following early life adversity

ABSTRACT Early life experience is critical in shaping the circuits that underlie adult behavior, and adversity or deprivation early in life robustly increases the risk for development of numerous neuropsychiatric disorders. In this project, we will investigate the role of serotonergic neurons in alterations in adult social behavior following early life adversity. Here, we will use the limited bedding and nesting model of early life adversity in mice to understand links between early experience, the serotonergic system, and social competition in dominance tasks. We will take a multidisciplinary approach, utilizing electrophysiology, behavioral assays, and fiber photometry to address the hypothesis that early life adversity leads to reduced excitability of serotonergic neurons and alterations in social dominance processing. In the first aim, we will examine the effect of bidirectionally modulating the activity of serotonergic neurons on social competition in adult mice who experienced early life stress. In the second, we will use fiber photometry to investigate early life adversity-induced alterations in serotonergic dynamics during competitive social behavior. These studies hold the potential to contribute significantly to our understanding of how the serotonergic system is altered by early life experience and may lead to novel avenues for the development of therapeutics for social symptoms of neuropsychiatric illnesses.