Christopher Machle Humanities and Social Science
The Neural Basis of Choice Rejection
The capacity to reject potential choices is critical to everyday function and is a core issue for multiple behavioral disorders, particularly addiction. Though a wealth of research displays that the subcortical region known as the striatum is a pivotal site for enacting value-based decisions, the mechanism underlying choice rejection is significantly understudied. Current research assumes a go/no-go heuristic that divides the two pathways of the striatum into discrete roles, asserting the direct pathway initiates decisions and the indirect pathway initiates rejections. Though the simplicity of this go/no-go heuristic is attractive, the predictions this heuristic makes about selection and rejection initiation do not fully hold when tested empirically. Consequently, my project is designed to illuminate the neural basis of rejection decisions by recording and manipulating the direct and indirect pathways in mice as they perform a complex foraging task optimized to temporally isolate rejection decisions from accept decisions. Given that indirect pathway excitation has shown to bias ipsilateral choice selection, I predict that rejection relies on indirect pathway excitation on the hemisphere opposite of stimulus presentation.