Do basal Ganglia amplify willed action by stochastic resonance? A model.

Basal ganglia are usually attributed a role in facilitating willed action, which is found to be impaired in Parkinson's disease, a pathology of basal ganglia. We hypothesize that basal ganglia possess the machinery to amplify will signals, presumably weak, by stochastic resonance. Recently we p...

Full description

Bibliographic Details
Main Author: V Srinivasa Chakravarthy
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2013-01-01
Series:PLoS ONE
Online Access:http://europepmc.org/articles/PMC3841152?pdf=render
_version_ 1828756728840192000
author V Srinivasa Chakravarthy
author_facet V Srinivasa Chakravarthy
author_sort V Srinivasa Chakravarthy
collection DOAJ
description Basal ganglia are usually attributed a role in facilitating willed action, which is found to be impaired in Parkinson's disease, a pathology of basal ganglia. We hypothesize that basal ganglia possess the machinery to amplify will signals, presumably weak, by stochastic resonance. Recently we proposed a computational model of Parkinsonian reaching, in which the contributions from basal ganglia aid the motor cortex in learning to reach. The model was cast in reinforcement learning framework. We now show that the above basal ganglia computational model has all the ingredients of stochastic resonance process. In the proposed computational model, we consider the problem of moving an arm from a rest position to a target position: the two positions correspond to two extrema of the value function. A single kick (a half-wave of sinusoid, of sufficiently low amplitude) given to the system in resting position, succeeds in taking the system to the target position, with high probability, only at a critical noise level. But for suboptimal noise levels, the model arm's movements resemble Parkinsonian movement symptoms like akinetic rigidity (low noise) and dyskinesias (high noise).
first_indexed 2024-12-10T23:21:55Z
format Article
id doaj.art-47821acaee364d9f953786b48c5b7ca8
institution Directory Open Access Journal
issn 1932-6203
language English
last_indexed 2024-12-10T23:21:55Z
publishDate 2013-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj.art-47821acaee364d9f953786b48c5b7ca82022-12-22T01:29:42ZengPublic Library of Science (PLoS)PLoS ONE1932-62032013-01-01811e7565710.1371/journal.pone.0075657Do basal Ganglia amplify willed action by stochastic resonance? A model.V Srinivasa ChakravarthyBasal ganglia are usually attributed a role in facilitating willed action, which is found to be impaired in Parkinson's disease, a pathology of basal ganglia. We hypothesize that basal ganglia possess the machinery to amplify will signals, presumably weak, by stochastic resonance. Recently we proposed a computational model of Parkinsonian reaching, in which the contributions from basal ganglia aid the motor cortex in learning to reach. The model was cast in reinforcement learning framework. We now show that the above basal ganglia computational model has all the ingredients of stochastic resonance process. In the proposed computational model, we consider the problem of moving an arm from a rest position to a target position: the two positions correspond to two extrema of the value function. A single kick (a half-wave of sinusoid, of sufficiently low amplitude) given to the system in resting position, succeeds in taking the system to the target position, with high probability, only at a critical noise level. But for suboptimal noise levels, the model arm's movements resemble Parkinsonian movement symptoms like akinetic rigidity (low noise) and dyskinesias (high noise).http://europepmc.org/articles/PMC3841152?pdf=render
spellingShingle V Srinivasa Chakravarthy
Do basal Ganglia amplify willed action by stochastic resonance? A model.
PLoS ONE
title Do basal Ganglia amplify willed action by stochastic resonance? A model.
title_full Do basal Ganglia amplify willed action by stochastic resonance? A model.
title_fullStr Do basal Ganglia amplify willed action by stochastic resonance? A model.
title_full_unstemmed Do basal Ganglia amplify willed action by stochastic resonance? A model.
title_short Do basal Ganglia amplify willed action by stochastic resonance? A model.
title_sort do basal ganglia amplify willed action by stochastic resonance a model
url http://europepmc.org/articles/PMC3841152?pdf=render
work_keys_str_mv AT vsrinivasachakravarthy dobasalgangliaamplifywilledactionbystochasticresonanceamodel