Probing the Influence of Testosterone on Ventromedial Hypothalamic Activity During Social Choice

Abstract

Social behavior, such as investigation or interest, mating, and aggression, drives day to day interactions. The choice to interact with a conspecific or social subject over a nonsocial subject is known as a social reward. The social reward circuit has been extensively studied and involves various subcortical and mesolimbic structures, such as the ventral tegmental area, nucleus accumbens, medial preoptic area, and the ventromedial hypothalamus ventrolateral area. Previous studies have also pointed to the role of sex hormones in mediating social behavior. This paper utilizes a two-choice social operant with automated reward (SOAR) paradigm to investigate how social behavior is altered in mice following testosterone injection. Additionally, we record neural activity from the ventromedial hypothalamus ventrolateral area to understand how neural activity in the region is affected under the influence of testosterone. Our results show successful learning on the operant task for social reward, decreased poke rates for social reward and an overall decrease in neural activity under the influence of testosterone, suggesting a decrease in social motivation. Further understanding of the potential role of the ventromedial hypothalamus and sex hormones drive social reward is crucial for understanding social motivation.