Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2002-5-14
pubmed:abstractText
Overt symptoms of Parkinson's disease do not manifest themselves until there is a substantial loss of the dopaminergic nigrostriatal projection. However, as neuroprotective strategies are developed, it will be essential to detect the disease in its preclinical phase. Performance on conditioned reaction time tasks is known to be impaired by extensive 6-hydroxydopamine-induced lesions of the nigrostriatal dopamine pathway. However, the effect of smaller lesions on a reaction time task has not been systematically assessed. We, therefore, used this test to examine behavioral deficits as a function of striatal dopamine loss. When injected at doses that produced striatal DA depletion <50%, 6-hydroxydopamine infused in the medial forebrain bundle produced no reliable impairment in the reaction time task. Higher doses producing > or = 60% DA depletion in the striatum produced a decrease in the percent correct responding throughout the 5 week testing period and akinetic deficits expressed by an increase in delayed responding. In addition, larger DA depletions (> or = 95%) profoundly altered motor control with decreases in percent correct responses, increases in delayed responses and increases in reaction time. These results suggest that reaction time may be a relatively sensitive measure of preclinical or subtle deficits, although it might be even more useful in quantitating the severity of depletion once overt deficits or symptoms appear and has the advantage of measuring such deficits over time to follow recovery of function. Furthermore since reaction time deficits required extensive loss of dopamine, these results are consistent with a predominant role of extrasynaptic dopamine in the mediation of relatively skilled motor tasks.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0893-133X
pubmed:author
pubmed:issnType
Print
pubmed:volume
26
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
756-64
pubmed:dateRevised
2011-5-18
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Effect of bilateral 6-hydroxydopamine lesions of the medial forebrain bundle on reaction time.
pubmed:affiliation
Department of Neurology, University of Pittsburgh, Pittsburgh, PA, USA
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.