Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
4342409 | Neuroscience | 2006 | 14 Pages |
Abstract
The prefrontal cortex has long been thought to subserve both working memory and “executive” function, but the mechanistic basis of their integrated function has remained poorly understood, often amounting to a homunculus. This paper reviews the progress in our laboratory and others pursuing a long-term research agenda to deconstruct this homunculus by elucidating the precise computational and neural mechanisms underlying these phenomena. We outline six key functional demands underlying working memory, and then describe the current state of our computational model of the prefrontal cortex and associated systems in the basal ganglia (BG). The model, called PBWM (prefrontal cortex, basal ganglia working memory model), relies on actively maintained representations in the prefrontal cortex, which are dynamically updated/gated by the basal ganglia. It is capable of developing human-like performance largely on its own by taking advantage of powerful reinforcement learning mechanisms, based on the midbrain dopaminergic system and its activation via the basal ganglia and amygdala. These learning mechanisms enable the model to learn to control both itself and other brain areas in a strategic, task-appropriate manner. The model can learn challenging working memory tasks, and has been corroborated by several important empirical studies.
Keywords
Substantia nigra pars reticulataHippocampal systemAX-CPTWCSTglobus pallidus, external segmentSTNVTASIRSNCPFCSNRGPEattention deficit hyperactivity disorderADHDTemporal differencePavlovian conditioningsubstantia nigra pars compactaDopaminebasal gangliaprefrontal cortexPosterior cortexComputational modelingventral tegmental areaSubthalamic nucleusReinforcement learning
Related Topics
Life Sciences
Neuroscience
Neuroscience (General)
Authors
T.E. Hazy, M.J. Frank, R.C. O'Reilly,