title: Motor-cortical interaction in Gilles de la Tourette syndrome.
abstract: BACKGROUND
  In Gilles de la Tourette syndrome (GTS) increased activation of the primary motor cortex (M1) before and during movement execution followed by increased inhibition after movement termination was reported. The present study aimed at investigating, whether this activation pattern is due to altered functional interaction between motor cortical areas.
  
  
  RESULTS
  10 GTS-patients and 10 control subjects performed a self-paced finger movement task while neuromagnetic brain activity was recorded using Magnetoencephalography (MEG). Cerebro-cerebral coherence as a measure of functional interaction was calculated. During movement preparation and execution coherence between contralateral M1 and supplementary motor area (SMA) was significantly increased at beta-frequency in GTS-patients. After movement termination no significant differences between groups were evident.
  
  
  CONCLUSIONS
  The present data suggest that increased M1 activation in GTS-patients might be due to increased functional interaction between SMA and M1 most likely reflecting a pathophysiological marker of GTS. The data extend previous findings of motor-cortical alterations in GTS by showing that local activation changes are associated with alterations of functional networks between premotor and primary motor areas. Interestingly enough, alterations were evident during preparation and execution of voluntary movements, which implies a general theme of increased motor-cortical interaction in GTS.
authors.affiliation: Medical Faculty, Institute of Clinical Neuroscience and Medical Psychology, University of Dusseldorf, Duesseldorf, Germany.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Franzkowiak
authors.forename: Bettina
authors.initials: B
authors.lastname: Pollok
authors.forename: Katja
authors.initials: K
authors.lastname: Biermann-Ruben
authors.forename: Martin
authors.initials: M
authors.lastname: Südmeyer
authors.forename: Jennifer
authors.initials: J
authors.lastname: Paszek
authors.forename: Götz
authors.initials: G
authors.lastname: Thomalla
authors.forename: Melanie
authors.initials: M
authors.lastname: Jonas
authors.forename: Michael
authors.initials: M
authors.lastname: Orth
authors.forename: Alexander
authors.initials: A
authors.lastname: Münchau
authors.forename: Alfons
authors.initials: A
authors.lastname: Schnitzler
mesh_terms: D000328:Adult; D001931:Brain Mapping; D002450:Cell Communication / Q000502:physiology*; D019054:Evoked Potentials, Motor / Q000502:physiology; D005260:Female; D005385:Fingers / Q000502:physiology / Q000503:physiopathology; D006801:Humans; D015225:Magnetoencephalography; D008297:Male; D009044:Motor Cortex / Q000166:cytology / Q000502:physiology*; D009068:Movement / Q000502:physiology; D060685:Sense of Coherence / Q000502:physiology; D005879:Tourette Syndrome / Q000503:physiopathology* / Q000523:psychology