Cerebellar damage diminishes long-latency responses to multijoint perturbations

Isaac Kurtzer, Paxson Trautman, Russell J. Rasquinha, Nasir H. Bhanpuri, Stephen H. Scott, Amy J. Bastian

Research output: Contribution to journalArticle

Abstract

Damage to the cerebellum can cause significant problems in the coordination of voluntary arm movements. One prominent idea is that incoordination stems from an inability to predictively account for the complex mechanical interactions between the arm's several joints. Motivated by growing evidence that corrective feedback control shares important capabilities and neural substrates with feedforward control, we asked whether cerebellar damage impacts feedback stabilization of the multijoint arm appropriate for the arm's intersegmental dynamics. Specifically, we tested whether cerebellar dysfunction impacts the ability of posterior deltoid to incorporate elbow motion in its long-latency response (R2 = 45-75 ms and R3 = 75-100 ms after perturbation) to an unexpected torque perturbation. Healthy and cerebellar-damaged subjects were exposed to a selected pattern of shoulder-elbow displacements to probe the response pattern from this shoulder extensor muscle. The healthy elderly subjects expressed a long-latency response linked to both shoulder and elbow motion, including an increase/decrease in shoulder extensor activity with elbow flexion/extension. Critically, cerebellar-damaged subjects displayed the normal pattern of activity in the R3 period indicating an intact ability to rapidly integrate multijoint motion appropriate to the arm's intersegmental dynamics. However, cerebellar-damaged subjects had a lower magnitude of activity that was specific to the long-latency period (both R2 and R3) and a slightly delayed onset of multijoint sensitivity. Taken together, our results suggest that the basic motor pattern of the long-latency response is housed outside the cerebellum and is scaled by processes within the cerebellum.

Original languageEnglish (US)
Pages (from-to)2228-2241
Number of pages14
JournalJournal of neurophysiology
Volume109
Issue number8
DOIs
StatePublished - 2013

Keywords

  • Feedback
  • Long-latency reflex
  • Multijoint dynamics

ASJC Scopus subject areas

  • Neuroscience(all)
  • Physiology

Fingerprint Dive into the research topics of 'Cerebellar damage diminishes long-latency responses to multijoint perturbations'. Together they form a unique fingerprint.

Cite this