Structural connectivity of the fore- and mid-brain in prairie voles.

Mammals live in complex social systems that require higher order cognition to process and display complex social behaviors. It is suggested that brain networks, such as the social decision-making network (SDMN), have evolved to process such information. Recent functional connectivity studies of the SDMN have revealed distinct network dynamics during different social events across several species. However, the structural mapping of this network is incomplete which limits structural-functional modeling. Here, we assess the structural connectivity of an extended SDMN as well as the fore- and mid-brain afferent projections with the use of cholera toxin subunit-B retrograde tracers and the prairie vole (Microtus ochrogaster), a socially monogamous rodent that displays complex social behaviors. This work greatly expands upon the limited structural connectivity of the vole social brain and highlights important regions within the SDMN and other highly innervated regions that may serve as information hubs.