Fifty patients with mild-to-moderate tardive dyskinesia (TD), who were
devoid of other clinically apparent movement abnormalities, and 70
neurologically normal controls were assessed with a battery of instruments
developed to measure and analyze the hyperkinetic movements of TD directly,
objectively, and noninvasively. The electro-mechanical features that most
consistently characterized and differentiated the TD group were a greater
variability of all movements, increased energy in the 1-2 Hz frequency band
in hand and foot movements, and a marked increase in movements during
distracting tasks. This instrumentation promises to be useful in
quantitating abnormal involuntary movements, in prospectively following
individual patients to scan for small deviations from an
instrument-established baseline, and in examining patients with combined
movement abnormalities.Abstract Teaser