Topic: D2-SPNs

Abnormal reward and threat processing are key players in psychiatric conditions such as eating disorders, addiction or depression. These functions are strongly regulated by the nucleus accumbens shell (NAcSh) which integrates emotional signals to regulate motor output. Historically the NAcSh was thought to consist of 2 pathways: dopamine 1 and 2 receptor-expressing striatal projection neurons (D1, D2-SPNs) which promoted reward and aversive behavior, respectively. Yet recent work has revealed that both cell types can promote either reward or aversion, depending on the NAcSh subregion or input/

The prevailing model of the basal ganglia motor control posits that the striatum, the input nucleus fo the basal ganglia, orchestrates the selection of voluntary actions through two circuits, the direct and the indirect pathways that oppose each other in thalamocortical activation. These circuits originate from two different populations of spiny projecting neurons (SPNs) projecting to different output structures and classically distinguished by differential expression of dopamine (DA) D1 receptor- and D2 receptor (D1-SPNs and D2-SPNs), respectively, regardless of SPNs co-expressing these two r