Deficits in rapid adjustments of movements according to task constraints in Parkinson's disease

Eugene Tunik, Sergei V. Adamovich, Howard Poizner, Anatol G. Feldman

Research output: Contribution to journalArticlepeer-review

14 Scopus citations


The role of the basal ganglia in the adaptive control of movement was investigated by unexpectedly perturbing movements in 8 patients with Parkinson's disease (PD) tested off medication and in 6 aged-matched healthy subjects. Subjects performed two movement components simultaneously and without visual feedback: touching the nose with the finger while leaning the trunk forward. Subjects wore a harness connected to an electromagnet, which was attached to a wall. The trunk movement was mechanically blocked in randomly selected trials by engaging the electromagnet. While healthy subjects performed the task equally well in both conditions, PD subjects' hand movements significantly deteriorated in trunk-perturbed compared to trunk-free trials. Deteriorated hand movements were characterized by segmented hand paths, unsmooth velocity profiles, and prolonged movement times. This finding indicated that the relatively local trunk perturbation had a global effect on the hand movement of PD subjects, necessitating them to reinitiate, after some delay, their arm movement in perturbed trials. Thus, the basal ganglia may be a critical node in brain networks mediating the flexibility of responses to altered motor states.

Original languageEnglish (US)
Pages (from-to)897-906
Number of pages10
JournalMovement Disorders
Issue number8
StatePublished - Aug 2004
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Neurology
  • Clinical Neurology


  • Basal ganglia
  • Frames of reference
  • Multisegmental control
  • Response to perturbation
  • Trajectory formation


Dive into the research topics of 'Deficits in rapid adjustments of movements according to task constraints in Parkinson's disease'. Together they form a unique fingerprint.

Cite this