Effects of unilateral pallidotomy on voluntary movement, and simple and choice reaction times in Parkinson's disease.
We studied the effects of unilateral pallidotomy on motor execution and reaction times in patients with moderately advanced Parkinson's disease (PD). Twelve consecutive patients (7 men, 5 women; all right-handed) underwent left-side microelectrode-guided pallidotomy. In addition to clinical rating, reaction time (RT) tests and repetitive movements of the contralesional hand/arm were carried out at baseline and 2 to 3 months after surgery while patients were on optimal medical regimens (on period). The initiation time in both simple reaction time (SRT) and choice reaction time (CRT) improved significantly after pallidotomy (P < 0.05), whereas no effect was observed on the choice processing time, which was calculated by subtracting the mean value of the onset of SRT from that of CRT. Pallidotomy resulted in significant improvement of repetitive movements such as hand pronation/supination and finger-tapping (P < 0.002, P < 0.005, respectively). Improvements in RT tests and repetitive movements suggest that pallidotomy may enhance attention and motor function. These effects are probably mediated through the pallido-thalamic-cortical neural circuitry.
Hayashi
Ryoichi
R
Department of Medicine (Neurology), Shinshu University School of Medicine, Matsumoto, Japan. rkhayasi@palette.plala.or.jp
Hashimoto
Takao
T
Tada
Tsuyoshi
T
Ikeda
Shu-ichi
S
D000368:Aged; D001288:Attention / Q000502:physiology; D002755:Choice Behavior; D005260:Female; D005542:Forearm / Q000502:physiology*; D007839:Functional Laterality / Q000502:physiology*; D005917:Globus Pallidus / Q000601:surgery*; D006225:Hand / Q000502:physiology*; D006801:Humans; D008297:Male; D008839:Microelectrodes; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000502:physiology*; D019635:Neurosurgical Procedures / Q000379:methods*; D010300:Parkinson Disease / Q000601:surgery*; D011184:Postoperative Period; D011597:Psychomotor Performance / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology*