Article Text

other Versions

PDF
Impaired sensorimotor integration in focal hand dystonia patients in the absence of symptoms.
  1. Carolyn C Wu1,
  2. Scott L Fairhall2,
  3. Nicolas A McNair1,
  4. Jeffrey P Hamm1,
  5. Ian J Kirk1,
  6. Ross Cunnington3,
  7. Tim Anderson4,
  8. Vanessa K Lim1,*
  1. 1 Department of Psychology, The University of Auckland, New Zealand;
  2. 2 Neuroimaging Laboratory, Fondazione Santa Lucia IRCCS, Italy;
  3. 3 Queensland Brain Institute and School of Psychology, The University of Queensland, Australia;
  4. 4 Van der Veer Institute for Parkinson's & Brain Research, The University of Otago, New Zealand
  1. Correspondence to: Vanessa Lim, University of Auckland, Department of Psychology, University of Auckland, Auckland, 1142, New Zealand; v.lim{at}auckland.ac.nz

Abstract

Functional imaging studies of people with focal hand dystonia (FHD) have indicated abnormal activity in sensorimotor brain regions. Few studies however, have examined FHD during movements that do not provoke symptoms of the disorder. It is possible therefore, that any differences between FHD and controls are confounded by activity due to the occurrence of symptoms. Thus, in order to characterize impairments in FHD patients during movements that do not induce dystonic symptoms, we investigated the neural correlates of externally-paced finger tapping movements. Functional MRI (fMRI) was used to compare FHD patients to controls with respect to activation in networks modulated by task complexity and hand used to perform simple and complex tapping movements. In the “complexity network”, FHD patients showed significantly less activity relative to controls in posterior parietal cortex, medial supplementary motor area (SMA), anterior putamen and cerebellum. In the “hand network”, FHD patients showed less activation than controls in primary motor (M1) and somatosensory (S1) cortices, SMA and cerebellum. Conjunction analysis revealed that FHD patients demonstrated reduced activation in the majority of combined network regions (M1, S1 and cerebellum). Dysfunction in FHD is widespread in both complexity and hand networks and impairments are demonstrated even when performing tasks that do not evoke dystonic symptoms. These results suggest that such impairments are inherent to, rather than symptomatic of, the disorder.

Statistics from Altmetric.com

Footnotes

    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.