Optogenetic Manipulation of Corticostriatal Pathways in Pavlovian Conditioned Approach
Undergraduates: Lynde Wangler, Kyle Czarnecki Aric Madayag
Faculty Advisor: Donita Robinson
Department: Psychology & Neuroscience
An increasing number of people experience addiction to substances, which often has profoundly detrimental cognitive, health, and social consequences. For that reason, investigation of the neural circuitry that can produce addiction vulnerability is exceedingly important. In this study, a rat model was utilized to try to delineate the functions of a specific cortico-striatal pathway in the brain. Optogenetics was used to activate the projection neurons from the lateral orbitofrontal cortex (lOFC) to the dorsolateral striatum (DLS), as both of these brain regions have been implicated in having an important role within the brain¿¿¿s addiction and reward circuitry. Stimulation was administered while rats completed a classical conditioning session in a behavior chamber. The paradigm of choice was Pavlovian conditioned approach, which allowed us to observe attentional biases to either a cue-predictive lever (interaction with which has been shown to be related to addictive tendencies) or a reward receptacle (interaction with which is indicative of goal-directed behaviors). It was originally posited that stimulation to this pathway would enhance negative feedback from the lOFC to the DLS, thereby inhibiting behaviors related to addictive tendencies (indicated by a cue bias towards the lever). However, the data seem to more strongly suggest that the role of this pathway influences goal-directed behaviors, as demonstrated by increased receptacle entries and decreased latencies.