title: Interaction between eye and hand movements in multiple sclerosis patients with intention tremor.
abstract: Deficient eye and hand movements are present in patients with multiple sclerosis. In the present study, eye and hand movements were simultaneously measured during visually guided wrist step-tracking tasks in 16 patients with intention tremor and 15 healthy controls. The coupling between eye and hand movements was analyzed during simultaneous eye-hand tracking, and interactions were studied by comparing the coordinated eye-hand condition with isolated eye- or hand-tracking conditions. Despite movement abnormalities, the onset of eye and hand movements was highly correlated and an invariant coupling between the saccadic completion time and hand peak velocity was found, suggesting that the temporal coupling was very much preserved. The differences between the experimental tracking conditions suggest that, in MS patients with intention tremor, the ocular system influenced the hand movements. Intention tremor amplitude was reduced when there was no preceding saccadic eye movement, whereas conversely, eye movements were not affected by different hand tremor severity.
authors.affiliation: Department of Kinesiology, Motor Learning Laboratory, Katholieke Universiteit Leuven, Tervuursevest 101, B-3001 Leuven, Belgium.
authors.forename: Peter
authors.initials: P
authors.lastname: Feys
authors.forename: Werner F
authors.initials: WF
authors.lastname: Helsen
authors.forename: Xuguang
authors.initials: X
authors.lastname: Liu
authors.forename: Bart
authors.initials: B
authors.lastname: Nuttin
authors.forename: Ann
authors.initials: A
authors.lastname: Lavrysen
authors.forename: Stephan P
authors.initials: SP
authors.lastname: Swinnen
authors.forename: Pierre
authors.initials: P
authors.lastname: Ketelaer
mesh_terms: D000328:Adult; D000368:Aged; D005133:Eye Movements / Q000502:physiology*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology*; D009103:Multiple Sclerosis / Q000503:physiopathology*; D011597:Psychomotor Performance / Q000502:physiology*; D014202:Tremor / Q000503:physiopathology*; D014953:Wrist / Q000294:innervation / Q000503:physiopathology