ABSTRACT
The largest of the basal ganglia nuclei, the dorsal striatum, integrates information about sensory and motor state conveyed by cortical and thalamic neurons, facilitating the selection of actions that achieve desirable outcomes, like reward, and avoid undesirable ones. Current models of how this happens have been built upon the notion that reward prediction errors signaled by mesencephalic dopaminergic neurons innervating the striatum provide a means by which experience shapes the strength of glutamatergic corticostriatal synapses and, in so doing, shapes action selection (Yin and Knowlton, 2006; Schultz, 2007; Cohen and Frank, 2009). One of the most compelling pieces of evidence for this view comes from the dif’culty of Parkinson’s disease (PD) patients, who have lost their striatal dopaminergic innervation, to readily choose context appropriate actions (Dujardin and Laurent, 2003).
