IMPAIRED MOVEMENT SEQUENCING IN PATIENTS WITH HUNTINGTONS-DISEASE - AKINEMATIC ANALYSIS

This experiment asked whether Huntington's disease, like Parkinson's d isease, another disorder of the basal ganglia, causes a specific progr essive deficit in the performance of sequential movement. Ten patients with Huntington's disease and their age-matched controls wrote the lo wer-case letter ''1'' four times in a linked cursive script, upon a gr aphics tablet which sampled pen position at 200 Hz. Kinematic features of sequential movement (stroke length, stroke duration, peak velocity , time to peak velocity and time from peak to zero velocity) were exam ined in a Group by Stroke Position (2 x 8) design, to identify which a spects of movement might show progressive disturbances. Unlike Agostin o et al. [Brain 115, 1481-1495, 1992], this experiment did in fact fin d progressive changes in the performance of sequential movements. Kine matic analysis indicated a progressive increase in movement duration d uring sequential movement, that Was associated with the accelerative p hase of movement.