Whole-Brain Map of Top-down afferent Inputs to Nucleus Accumbens of the Mouse

ABSTRACT Nucleus accumbens (NAc) is an important part of basal ganglia and receives major transsynaptic inputs from medial prefrontal cortex (mPFC), basolateral amygdala nucleus (BL) and hippocampus (HPC). The neural circuits formed by mPFC, BL, HPC with NAc are closely related to diverse brain functions such as decision-making, social behavior, reward seeking behavior and aggressive behavior. However, a lack of information about network structure of NAc top-down afference has limited our understanding of mechanisms of these functions. Here, we systematically analyzed whole brain patterns of inputs to mPFC/HPC/BL-NAc projectors via using (TRIO) labeling strategy. We found that the upstream input patterns between mPFC-core and mPFC-shell projections, BL-core and BL-shell projections, HPC-core and HPC-shell projections were similar. The projections from mPFC and BL to NAc receive a wide range of inputs, while the projections from HPC to NAc receive convergent inputs. Furthermore, all of mPFC/HPC/BL-NAc projectors receive considerable inputs from respective local regions. This study lays a foundation for further analysis of complex NAc functional mechanisms.