Impairment of post-movement beta synchronisation in parkinson's disease is related to laterality of tremor.
OBJECTIVE
Post-movement beta synchronisation (PMBS) is a physiological indicator of the activity of movement related neural networks. To investigate the pathophysiology of this phenomenon, we examined its characteristics in patients with unilateral tremor-dominant Parkinson's disease (PD).


METHODS
Movement duration and PMBS was measured after self-paced movement of the thumb at movement-reactive beta frequencies, over the supplementary motor area in 10 PD patients and 8 control subjects.


RESULTS
Movement duration in PD patients was longer than in controls. In left hand tremor patients, movement of the left hand was significantly longer compared to the right hand. When PD patients moved their non-affected hand, similarly to the controls, PMBS was higher contralateral to the movement. After movement of the tremulous hand, the contralateral PMBS decreased significantly and the contralateral preponderance disappeared. In the same hemisphere, PMBS was higher after contralateral to the non-affected hand movement, than after ipsilateral to the tremulous hand after movement.


CONCLUSIONS
PMBS in PD is affected by the activity of tremor related neural networks, suggesting that both cortical and subcortical sources are responsible for its generation. Examination of PMBS in various neurological diseases might provide further data on its physiological significance.
Tamás
Gertrúd
G
Department of Neurology, Semmelweis University Budapest, Hungary, 1083, Balassa u. 6., Budapest, Hungary.
Szirmai
Imre
I
Pálvölgyi
László
L
Takáts
Annamária
A
Kamondi
Anita
A
D000368:Aged; D001611:Beta Rhythm; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006225:Hand; D006801:Humans; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology; D010300:Parkinson Disease / Q000175:diagnosis* / Q000503:physiopathology*; D014202:Tremor / Q000175:diagnosis / Q000503:physiopathology