Article Text

Download PDFPDF
Myotatic reflexes and the on-off effect in patients with Parkinson's disease.
  1. J R Dufresne,
  2. J F Soechting,
  3. E S Tolosa

    Abstract

    Reflex activity in the biceps and triceps muscles evoked by applied torque perturbations was studied in patients with Parkinson's disease. The perturbations consisted of single pulses or of pseudo-random sequences of pulses of torque. The patients were treated with levodopa and some exhibited marked fluctuations in their clinical disabilities ("on-off" effect). The study was undertaken to see if reflex activity changed in parallel with the fluctuations of their clinical symptoms. It was found that the reflex activity in these patients could be classified into two types, a Type I response differing little from normal and a Type II response exhibiting marked high-frequency (8-14 Hz) oscillations in EMG activity. Both Type I and Type II responses were virtually the same in the "on" as in the "off" state.

    Statistics from Altmetric.com

    Request Permissions

    If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.