Factors affecting reaction and movement times in hemiparetic patients and in healthy subjects

The effects of body side, joint location (proximal and distal) and movement type (uni lateral and bilateral) on reaction and movement times (RT, MT) were studied in three groups of subjects: aged and young healthy subjects and hemiparetic elderly patients. Reaction time was measured relative to an auditory signal. Movement time was mea sured for 20° of elbow flexion and for a linear movement of 3 mm performed by the thumb. Each movement was repeated five times unilaterally on each side and five times bilaterally. The findings pointed to longer RTs and MTs in the aged subjects than in the young subjects and in the proximal joints than in the distal joints. Both RT and MT were lengthened on the paretic extremity in the patients, while no right-left differences were encountered in the healthy subjects. Bilateral movements caused slowing of RT in the hemiparetic patients and significant slowing of MT in all three groups. The sep arate as well as interactive effects of these variables on movement speed, as reflected in RT and MT, warrant consideration during planning of rehabilitation treatment pro grams for hemiparetic patients.