title: Altered force release control in Parkinson's disease.
abstract: Isometric force tracking and force aiming modified by visual feed-back was investigated in Parkinsonian (PD) and control subjects. Production and maintenance of isometric force, production and release of isotonic force, and maximum force were tested. Statistical analysis revealed that the PD patients could perform most force tasks in a similar manner to that of control subjects. However, PD patients had difficulties in sustaining target force over a 30-s period and in performing rapid alternating movements. The major finding in PD patients was an inability to precisely release a target force. Overall these data suggest that the release of a produced force is a sensitive motor control parameter in Parkinson's disease.
authors.affiliation: Department of Neurology, Heinrich-Heine University, Düsseldorf, FRG.
authors.forename: E
authors.initials: E
authors.lastname: Kunesch
authors.forename: A
authors.initials: A
authors.lastname: Schnitzler
authors.forename: C
authors.initials: C
authors.lastname: Tyercha
authors.forename: S
authors.initials: S
authors.lastname: Knecht
authors.forename: G
authors.initials: G
authors.lastname: Stelmach
mesh_terms: D000328:Adult; D005246:Feedback; D005260:Female; D005385:Fingers / Q000473:pathology*; D007839:Functional Laterality; D006801:Humans; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D009068:Movement; D010300:Parkinson Disease / Q000503:physiopathology*; D011930:Reaction Time; D014794:Visual Fields