The role of the dorsomedial striatum in instrumental conditioning

Considerable evidence suggests that, in instrumental conditioning, rats learn the relationship between actions and their specific consequences or outcomes. The present study examined the role of the dorsomedial striatum (DMS) in this type of learning after excitotoxic lesions and reversible, muscimol-induced inactivation. In three experiments, rats were first trained to press two levers for distinct outcomes, and then tested after training using a variety of behavioural assays that have been established to detect action-outcome learning. In Experiment 1, pre-training lesions of the posterior DMS abolished the sensitivity of rats' instrumental performance to both outcome devaluation and contingency degradation…

• NS
  National Science Foundation
• NI
  National Institute of Mental Health