Action-suppression in the basal ganglia: mediated by a neural implementation of the Race-model?

点击翻译按钮获取中文摘要

In this project proposal, I aim at understanding the role of the basal ganglia in decision-making. In particular, I study the neural algorithm underlying the suppression of unwanted actions. Experimental studies examine action-suppression e.g. in simple tasks where the animal has to prevent or cancel specific actions if a certain sensory stimulus occurs. Action-suppression has been successfully modeled with the so-called Race-model. The main research objective of this proposal is to test the hypothesis that action-suppression in the basal ganglia is mediated by a neural implementation of the Race-model. To test this hypothesis, I will create a novel computational model of the basal ganglia that implements the Race-model for action-suppression, which allows us to identify fundamental mechanisms of decision-making in terms of the integration of action-facilitating and action-suppressing signals in the basal ganglia. Furthermore, using the new model, I plan to study extinction-learning, i.e. learning to stop responding when the response is no longer rewarded. In particular, I hypothesize that the indirect pathway in the basal ganglia is a crucial neural circuit for the extinction of a conditioned response. I would like to perform these projects in the lab of Dr. Berke (University of Michigan) because I will have access to existing and newly acquired experimental data sets to design and to constrain the models. Furthermore, in close interaction with the lab, I can test predictions arising from the computational models through analysis of the electrophysiological data, and I will also suggest new experiments based on the model results. The results of this project are relevant to understand both normal and pathological behavior, e.g. in gambling, Tourette syndrome, and Parkinson Disease.