Deiber M P, Caldara R, Ibañez V, Hauert C A
Faculté de Psychologie et des Sciences de l'Education, Université de Genève, UniMail, Boulevard du Pont d'Arve 40, CH-1211 4, Geneva, Switzerland.
Clin Neurophysiol. 2001 Aug;112(8):1419-35. doi: 10.1016/s1388-2457(01)00536-3.
To investigate the cortical activation during execution of unimanual and bimanual synchronous and asynchronous finger sequences, as well as during transitions between those sequences.
Task-related power (TRPow) analysis of multichannel surface EEG was used to examine the regional oscillatory brain activity in the lower (7.8-9.8 Hz) and upper (10.8-11.8 Hz) alpha band. Unimanual to bimanual, bimanual to unimanual, and unimanual to unimanual transitions, prompted by visual cues, were studied in 10 right handed subjects.
(1) Execution of unimanual and bimanual movements was accompanied by a bilateral activation over the central regions. (2) The 7.8-9.8 Hz TRPow decrease was more prominent for left and bimanual movements, suggesting sensitivity of the lower alpha band to task difficulty. (3) No difference in alpha oscillatory activity was found between bimanual synchronous and asynchronous sequences. (4) Transitions between motor sequences were invariably accompanied by a mesioparietal TRPow decrease in the lower alpha band. (5) This mesioparietal activation was contingent to the change of motor program, and could not be accounted for by the change of visual cue, or related attentional processes.
The 7.8-9.8 Hz mesioparietal activation most likely reflects a posterior parietal motor command initiating transition between motor programs.
研究单手和双手同步及异步手指序列执行过程中，以及这些序列之间转换时的皮层激活情况。
采用多通道表面脑电图的任务相关功率（TRPow）分析，来检测较低（7.8 - 9.8 Hz）和较高（10.8 - 11.8 Hz）α波段的局部振荡脑活动。在10名右利手受试者中，研究了由视觉线索提示的单手到双手、双手到单手以及单手到单手的转换。
（1）单手和双手运动的执行伴随着中央区域的双侧激活。（2）较低α波段（7.8 - 9.8 Hz）的TRPow下降在左手和双手运动时更为显著，表明较低α波段对任务难度敏感。（3）双手同步和异步序列之间的α振荡活动没有差异。（4）运动序列之间的转换总是伴随着较低α波段中顶叶TRPow的下降。（5）这种中顶叶激活取决于运动程序的变化，不能用视觉线索的变化或相关的注意力过程来解释。
7.8 - 9.8 Hz的中顶叶激活很可能反映了顶叶后部运动指令启动运动程序之间的转换。
