Serrien Deborah J
School of Psychology, University of Nottingham, University Park, Nottingham, NG7 2RD, UK.
Eur J Neurosci. 2008 Mar;27(6):1553-60. doi: 10.1111/j.1460-9568.2008.06110.x. Epub 2008 Mar 10.
Distinct processing that integrates an accurate time scale is necessary for optimal motor behaviour. In the present study, corticocortical interactions as determined by EEG coherence were assessed in a synchronization-continuation paradigm during which subjects initially performed tapping movements in synchrony with external cues, followed by internal pacing of the target interval when the metronome was switched off. Unimanual and bimanual tasks were executed, and continuation of tapping was conducted with the same or different effector(s). The data showed an increased degree of mesial-central connectivity in the unpaced as compared to paced performance that was independent of task complexity, pointing to a general intensified demand of temporal processing when external cues are unavailable. When switching temporal information between effectors, coherence increased across the motor network. This increase depended upon preceding task complexity, and was most prominent for interhemispheric connections when performing unimanual tasks following bimanual pacing. Overall the data illustrate that timing of skilled actions can easily be transferred between effectors, although increased neural resources are required to conform to the temporal and motor constraints.
整合精确时间尺度的独特处理对于最佳运动行为是必要的。在本研究中，通过脑电图相干性确定的皮质间相互作用在同步 - 延续范式中进行评估，在此范式中，受试者最初与外部线索同步进行敲击运动，然后在节拍器关闭时对目标间隔进行内部计时。执行单手和双手任务，并且用相同或不同的效应器进行敲击延续。数据显示，与有节奏的表现相比，无节奏表现中内侧 - 中央连接程度增加，这与任务复杂性无关，表明当没有外部线索时，对时间处理的总体需求增加。当在效应器之间切换时间信息时，整个运动网络的相干性增加。这种增加取决于先前的任务复杂性，并且在双手节奏后执行单手任务时，半球间连接最为明显。总体而言，数据表明，熟练动作的计时可以很容易地在效应器之间转移，尽管需要增加神经资源以符合时间和运动限制。
