Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030567 (Parkinson's disease)
 63,064 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Impairment in the inhibitory mechanism of visual selective attention in patients with Parkinson's disease (PD) is controversial. The present study sought to understand disparate findings in a manner analogous to the relative preservation of exogenously evoked movement and impairment of endogenously evoked movement. The authors examined inhibition of return (i.e., exogenously evoked inhibition; IOR) and negative priming (i.e., endogenously evoked inhibition; NP) in a group of 14 patients with PD and 14 healthy controls (HC). Unlike the HC, who demonstrated significant inhibition in both tasks, the group with PD demonstrated intact inhibition only in the IOR task. Dopamine replacement therapy did not affect performance. The findings are discussed within the context of a model that differentiates the essential involvement of the basal ganglia for endogenously evoked spatial inhibition.
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PMID:Visual selective attention in Parkinson's disease: dissociation of exogenous and endogenous inhibition. 1671 30

Cognitive impairments in patients with basal ganglia dysfunction are primarily revealed where performance relies on internal, voluntary control processes. Evidence suggests that this also extends to impaired control of more automatic processes, including visuospatial attention. The present study used a non-predictive peripheral cueing paradigm to compare and contrast visuospatial deficits in patients with Parkinson's disease (PD) with those previously revealed in patients with Huntington's disease (HD) (Fielding et al., 2006a). Compared to age-matched controls, both PD and HD patients exhibited increased distractibility or poor fixation, however only PD patients responded erroneously to cue stimuli more frequently than control subjects. All subjects demonstrated initial facilitation for valid versus invalid cues following the shorter stimulus-onset asynchronies (SOAs) and a performance decrement at the longer SOAs (inhibition of return), although there was a clear differentiation between these groups for immediate SOAs. Unlike both control and PD subjects, where IOR manifested between 350 and 1000 msec, IOR was evident as early as 150 msec for HD patients. Further, for PD patients, spatially valid cues resulted in hyper-reflexivity following 150 msec SOAs, with saccadic latencies shorter than those generated in response to un-cued targets. Thus contrasting deficits were revealed in PD and HD, emphasizing the important contribution of the basal ganglia in the control of more automatic behaviors
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PMID:The role of the basal ganglia in the control of automatic visuospatial attention. 1696 47