Dopamine and memory function in Parkinson's disease.
Response fluctuations in motor function, complicating long-term dopaminomimetic therapy of Parkinson's disease, may extend to the cognitive realm. To evaluate the effect of levodopa treatment both on attention as well as acquisition and retrieval of memory tasks, parkinsonian patients were examined neuropsychologically both while medicated with levodopa/carbidopa ("on") and when the medication's antiparkinsonian effect had worn off ("off"). Significant cognitive differences emerged only on the delayed recall of complex verbal materials, where patients when "on" performed better compared with their "off" state. Comparison of change scores across states (administration or withholding of levodopa/carbidopa between acquisition and retrieval, "off" to "on" or "on" to "off"), revealed no substantial differences as a function of dopaminomimetic therapy. These results support the view that slight changes in cognition are associated with dopaminomimetic therapy of Parkinson's disease, but that these changes may be task-specific.
Mohr
E
E
Medical Neurology Branch, National Institute of Neurological and Communicative Disorders and Stroke, Bethesda, Maryland 20892.
Fabbrini
G
G
Williams
J
J
Schlegel
J
J
Cox
C
C
Fedio
P
P
Chase
T N
TN
D000368:Aged; D001288:Attention / Q000502:physiology; D001921:Brain / Q000503:physiopathology; D002230:Carbidopa / Q000008:administration & dosage; D004298:Dopamine / Q000502:physiology*; D004338:Drug Combinations / Q000008:administration & dosage; D005260:Female; D006801:Humans; D007980:Levodopa / Q000008:administration & dosage; D008297:Male; D008568:Memory / Q000502:physiology*; D011939:Mental Recall / Q000502:physiology*; D008875:Middle Aged; D009048:Motor Skills / Q000502:physiology; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000188:drug therapy / Q000503:physiopathology*; D010364:Pattern Recognition, Visual / Q000502:physiology; D011954:Receptors, Dopamine / Q000502:physiology*; D009435:Synaptic Transmission / Q000187:drug effects; D014706:Verbal Learning / Q000502:physiology
D004338:Drug Combinations; D011954:Receptors, Dopamine; C009265:carbidopa, levodopa drug combination; D007980:Levodopa; D002230:Carbidopa; D004298:Dopamine