A meta-analysis on cognitive slowing in Parkinson's disease: are simple and choice reaction times differentially impaired?
Meta-analysis was conducted to determine whether patients with Parkinson's disease (PD) are differentially affected when confronted with choice reaction time (RT) tasks as compared to simple RT tasks (1548 PD patients compared to 1648 age-matched controls). While medicated PD patients were slower than controls in all RT conditions, their simple, choice, and discrimination RT followed the same patterns as controls. Severity of disease was found to affect RT but precue availability and tremor did not. Overall findings indicate that movement initiation slowing remained constant across response uncertainty conditions, suggesting that medicated PD patients do not have a response selection impairment.
Wang
J
J
Motor Control Laboratory, Arizona State University. Tempe, AZ 85287-0404, USA.
Thomas
J R
JR
Stelmach
G E
GE