[Electrophysiologic investigation of cerebral cortex in the subtypes of Parkinson disease].
OBJECTIVE
Post-movement beta synchronization is an increase in EEG beta power after movement termination. Its characteristics in movement disorders are not well described. Tremor dominant Parkinson's disease shows unique clinical, anatomical and biochemical features. In our study we examined the relation between the laterality of tremor and size of post-movement beta synchronisation in tremor dominant Parkinson's disease.


METHODS
In a self-paced movement paradigm we measured movement duration and analyzed EEG power changes at movement-reactive beta frequencies.


RESULTS
Movement duration was significantly longer in Parkinson-patients than in controls (0.49 +/- 0.170 s, 0.35 +/- 0.087 s, p = 0.013, Mann-Whitney test). There was no difference between the two hands in the control group (0.36 +/- 0.078 s, 0.34 +/- 0.099 s, p = 0.207, Wilcoxon-test), while Parkinson patients performed longer movement with their left hand (0.52 +/- 0.195 s, 0.46 +/- 0.148 s, p = 0.049, Wilcoxon), unrelated to the side of tremor. In controls, post-movement beta synchronisation contralateral to the movement was not significantly different after right and left hand movement (108.1 +/- 68.21% and 92.1 +/- 23.43%, p = 0.78 Wilcoxon). In Parkinson patients post-movement beta synchronisation was significantly smaller contralateral to the tremulous hand movement (36.9 +/- 47.79%, 104.7 +/- 91.42%, p = 0.012, Wilcoxon-test). The post-movement beta synchronisation showed anterior shifting in Parkinson-patients.


CONCLUSIONS
In tremor dominant Parkinson's disease the asymmetric decrease of post-move beta synchronisation is related to the laterality of tremor rather than bradykinesia. Analysis of this phenomena might provide further insight to the pathophysiology of Parkinson's disease.
Szirmai
Imre
I
Semmelweis Egyetem, Altalános Orvostudományi Kar, Neurológiai Klinika, Budapest. szirmai@neur.sote.hu
Tamás
Gertrúd
G
Takáts
Annamária
A
Pálvölgyi
László
L
Kamondi
Anita
A
D000368:Aged; D001611:Beta Rhythm; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000503:physiopathology*; D004569:Electroencephalography; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D008875:Middle Aged; D020734:Parkinsonian Disorders / Q000150:complications / Q000503:physiopathology*; D014202:Tremor / Q000209:etiology / Q000503:physiopathology