Role of the Prefrontal Cortex to Dorsomedial Striatum Projections in Compulsive Alcohol Drinking

Abstract

Compulsive alcohol drinking is a defining feature of alcohol use disorder and is characterized as drinking alcohol despite knowledge of negative consequences. This behavior is hypothesized to be due to a disruption in the decision-making process. Decision making relies on a balance between goal-directedness and habit systems to efficiently execute behavior. An important distinction between compulsive and non-compulsive individuals is the ability to withhold drinking in the face of a negative consequence. The dorsomedial striatum (DMS) and dorsomedial prefrontal cortex (dmPFC) are brain regions necessary for goal directed behavior where the dmPFC is important for cognitive control and behavioral inhibition while the DMS is important for action selection. Importantly, the dmPFC sends a glutamatergic input to the DMS. We hypothesize this input is a behavioral control which is necessary to withhold action selection. Thus, in order to maintain non-compulsive alcohol use, the dmPFC and DMS need to work together to orchestrate inhibition of action selection in the face of negative consequences. Previous research shows a causal role for both the dmPFC and DMS in preventing compulsive alcohol drinking and a role for the projections from the dmPFC to DMS in behavioral inhibition. However, no research has demonstrated a role for this circuit’s activity in prevention of compulsive alcohol use. The current experiment tested the hypothesis that inhibiting the glutamatergic projection from the dmPFC to the DMS will cause non-compulsive Wistar rats to drink alcohol compulsively.