Redwood Neuroscience
Title: “Error-correcting Feedback and Associative
Learning:
Computational
and Empirical Studies of Dopamine and Cortico-Striatal
Loops”
Center for Molecular and
Behavioral
Neuroscience
Abstract:
Converging evidence from neurocomputational models, neuroimaging, neuroanatomy, and
neurophysiology implicate the midbrain dopaminergic
system for processing error-correcting feedback. This feedback is essential for
learning to predict future rewards and the consequences of our actions.
Recent research from our laboratory has shown how this
view of dopamine and feedback in learning provides a means for
interpreting and understanding the complex pattern of spared and impaired
cognitive abilities seen in Parkinson's patients who have depleted
midbrain dopamine production. We have studied how learning in Parkinson's
patients is affected by dopaminergic medication and
other therapeutic interventions. In other work we have shown how certain
behavioral training techniques are effective for helping Parkinson's patients
overcome their cognitive limitations. A parallel line of functional neuroimaging studies provides converging evidence for the
role of these structures in error-correction learning and feedback processing.
Comparisons to other patient populations provide additional insights: we find a
double dissociation between the learning deficits in patients with medial
temporal damage (elderly with mild hipocampal
atrophy) as compared to patients with basal ganglia dysfunction (mild
Parkinson's disease), just as predicted by our prior computational model
of cortico-hippocampal processing. These results
suggest distinct contributions of the medial temporal lobe and basal ganglia in
learning and memory. These empirical studies provide the basis for future
exploration and development of more physiologically detailed neurocomputational models of cortico-striato-hippocampal
interaction in associative learning and memory
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