title: Pallidal stimulation for cervical dystonia does not correct abnormal temporal discrimination.
abstract: BACKGROUND
  We investigated whether clinical improvement observed after deep brain stimulation (DBS) of the globus pallidus internus (GPi) in cervical dystonia (CD) is paralleled by the normalisation of temporal discrimination thresholds (TDTs), a marker of abnormal sensory processing in CD.
  
  
  METHODS
  TDT was tested in 11 patients with CD after they received DBS and was compared with TDT scores from 24 patients with CD and a group of 61 controls.
  
  
  RESULTS
  A clear clinical response to GPi-DBS was demonstrated (total Toronto Western Spasmodic Torticollis Rating Scale scores fell from 50 to 18; P < 0.001). In contrast, TDT remained abnormal in the CD-DBS group (P < 0.001) and was not significantly different from the abnormal TDT range observed in CD.
  
  
  CONCLUSIONS
  Underlying sensory abnormalities in temporal discrimination observed in dystonia do not seem to be corrected by successful GPi-DBS. This adds further data to the ongoing debate regarding which pathophysiological abnormalities observed in dystonia are likely to be causal in the genesis of the disease rather than epiphenomena observed secondary to abnormal motor activity.
authors.affiliation: Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London, London, United Kingdom.
authors.forename: Anna
authors.initials: A
authors.lastname: Sadnicka
authors.forename: Okka
authors.initials: O
authors.lastname: Kimmich
authors.forename: Claudia
authors.initials: C
authors.lastname: Pisarek
authors.forename: Diane
authors.initials: D
authors.lastname: Ruge
authors.forename: Joe
authors.initials: J
authors.lastname: Galea
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Kassavetis
authors.forename: Isabel
authors.initials: I
authors.lastname: Pareés
authors.forename: Tabish
authors.initials: T
authors.lastname: Saifee
authors.forename: Anna
authors.initials: A
authors.lastname: Molloy
authors.forename: David
authors.initials: D
authors.lastname: Bradley
authors.forename: Sean
authors.initials: S
authors.lastname: O'Riordan
authors.forename: Ludvic
authors.initials: L
authors.lastname: Zrinzo
authors.forename: Marwan
authors.initials: M
authors.lastname: Hariz
authors.forename: Kailash P
authors.initials: KP
authors.lastname: Bhatia
authors.forename: Patricia
authors.initials: P
authors.lastname: Limousin
authors.forename: Thomas
authors.initials: T
authors.lastname: Foltynie
authors.forename: John C
authors.initials: JC
authors.lastname: Rothwell
authors.forename: Michael
authors.initials: M
authors.lastname: Hutchinson
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Edwards
mesh_terms: D000328:Adult; D000368:Aged; D046690:Deep Brain Stimulation / Q000379:methods*; D005260:Female; D005917:Globus Pallidus / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010468:Perceptual Disorders / Q000209:etiology* / Q000628:therapy*; D012720:Severity of Illness Index; D014103:Torticollis / Q000150:complications* / Q000628:therapy*
keywords: cervical dystonia; deep brain stimulation; temporal discrimination threshold