Disynaptic Prefrontal Cortical Input to the Dorsolateral Striatum

Abstract

The dorsomedial striatum (DMS) is responsible for actions that are reversible, goal-directed, and require attentional oversight. In contrast, the dorsolateral striatum (DLS) is responsible for relatively irreversible, but precise habitual actions that need little attentional oversight. In addiction, the balance between these two action strategies is shifted toward habits, leading to compulsive behaviors. The DMS is activated by input from executive, prefrontal cortical areas of the brain, while the DLS is activated by sensorimotor cortices. A major gap in knowledge is how executive cortical centers may mediate shifts away from habitually performed actions. While no executive cortical areas monosynaptically activate the DLS, we hypothesize the existence of disynaptic circuits allowing executive cortical control of the DLS. To test this, we utilized trans-synaptic target specific tracing (TranSTart) to reveal that executive cortices disynaptically project to the DLS through the basolateral amygdala (BLA) and the rostral intralaminar nuclei of the thalamus (rILN).