Motor cortex reorganisation in Parkinson's disease.
Transcranial magnetic stimulation mapping of the motor cortical projection to the hand was performed in a group of patients with Parkinson's disease (PD) of variable duration to determine whether there is evidence of cortical reorganisation. Map shifts were found in the majority of PD cases (12/15), in untreated early cases as well as treated cases of longer duration, and there was a correlation between inter-side difference in the severity of PD symptoms (Unified Parkinson's Disease Rating Scale) and interhemispheric map displacement (r=0.60; P=0.018). These findings indicate that there is reorganisation of the corticomotor representation of the hand in PD, even at a relatively early stage of the disease, and suggest a dynamic process of reorganisation in the motor cortex due to an increase in the pallidal inhibitory inputs to the thalamo-cortical projections.
Thickbroom
Gary W
GW
Centre for Neuromuscular and Neurological Disorders, University of Western Australia, Brain Research Laboratory, Queen Elizabeth II Medical Center, Nedlands, WA 6009, Australia. gthickbr@cyllene.uwa.edu.au
Byrnes
Michelle L
ML
Walters
Susan
S
Stell
Rick
R
Mastaglia
Frank L
FL
D000368:Aged; D001931:Brain Mapping; D019054:Evoked Potentials, Motor / Q000502:physiology / Q000528:radiation effects; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000473:pathology* / Q000503:physiopathology*; D010300:Parkinson Disease / Q000473:pathology / Q000503:physiopathology*; D050781:Transcranial Magnetic Stimulation / Q000379:methods