Experimental Brain Research

, Volume 177, Issue 4, pp 447–457

Impaired inhibitory oculomotor control in patients with Parkinson’s disease

  • Prakash Joti
  • Shrikanth Kulashekhar
  • Madhuri Behari
  • Aditya Murthy
Research Article

DOI: 10.1007/s00221-006-0687-0

Cite this article as:
Joti, P., Kulashekhar, S., Behari, M. et al. Exp Brain Res (2007) 177: 447. doi:10.1007/s00221-006-0687-0

Abstract

A hallmark of voluntary control is the capacity to inhibit or change partially prepared responses, an ability thought to be compromised in patients with Parkinson’s disease (PD). To test this hypothesis in relation to oculomotor control, PD patients and age-matched controls performed a redirect task in which they were instructed to cancel a partially prepared saccade on some random fraction of trials. Using a race model framework, the time it takes to cancel a saccade, the target switch reaction time (TSRT), was estimated for PD and control subjects. While saccadic reaction times of control and PD subjects were similar, the average TSRT in PD subjects was 139 ms, and was significantly greater than the TSRT in controls, which was 113 ms. These results support the hypothesis that poor voluntary control exhibited by PD patients in a variety of complex behaviors may be caused by impaired inhibitory control as a result of basal ganglia dysfunction.

Keywords

CountermandingDouble-stepSaccadesReaction-time

Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • Prakash Joti
    • 1
  • Shrikanth Kulashekhar
    • 1
  • Madhuri Behari
    • 2
  • Aditya Murthy
    • 1
  1. 1.National Brain Research CentreManesarIndia
  2. 2.Department of Neurology, C.N. CentreAll India Institute of Medical SciencesNew DelhiIndia