Reaction time responses in parkinsonian and hemiparkinsonian patients.

Twenty-one normal subjects, 32 bilateral parkinsonian patients (BPs) and 29 hemiparkinsonian patients (HP) were submitted to separate or sequentially associated motor tasks that included simple reaction times (RT), choice RTs, directional RTs, and movement RTs. The results showed that simple RTs, directional RTs, and movement times (MT) were slower in BPs as compared to normal subjects; for choice RTs there was no difference. Response patterns were similar in normal controls and BPs. In both groups RTs became more prolonged as sequentially programmed operations increased. If movement occurred at the end of the sequence, they prolonged the RTs of the preceding operations, but MTs per se did not vary. In HPs the same results were observed on the "bad" hand side versus normal controls and versus the healthy side, but a significant statistical level was reached mainly when the "bad" hand was the right one.