Immediate Early Gene Expression in D1-SPNs and D2-SPNs During a Striatum-dependent Reinforcement Learning Task

Dopamine signaling is thought to alter the excitability of the striatum’s principal neurons (D1- and D2-SPNs). We used immunohistochemistry to quantify the expression of Fos, a marker of neural activity, in mice trained in a head-fixed, striatum-dependent fear conditioning task. We observed a relative increase in Fos-expressing D1- vs D2-SPNs, which may indicate how activity in these neurons facilitates motor learning. Our findings have implications for understanding disease processes that affect the dopamine system, such as Parkinson’s disease and schizophrenia