Thaut Michael H, Stephan Klaus M, Wunderlich Gilbert, Schicks Wilfried, Tellmann Lutz, Herzog Hans, McIntosh Gerald C, Seitz Ruediger J, Hömberg Volker
Center for Biomedical Research in Music, Colorado State University, Fort Collins, CO 80523, USA.
Cortex. 2009 Jan;45(1):44-53. doi: 10.1016/j.cortex.2007.09.009. Epub 2008 Nov 7.
We investigated the role of the cerebellum in differential aspects of temporal control of rhythmic auditory motor synchronization using positron emission tomography (PET). Subjects tapped with their right index finger to metronome tones at a mean frequency of .8 Hz during 5 conditions: (1) an isochronous rhythm condition, (2) random changes in interval durations, and while the duration of rhythmic intervals was continuously time-modulated following a cosine-wave function at (3) 3%, (4) 7%, and (5) 20% of base interval. Anterior lobe cerebellar neuronal populations showed similar motor-associated activity across all conditions regardless of rhythmic time structure in vermal and hemispheric parts ipsilateral to the movements. Neuronal populations in bilateral anterior posterior lobe, especially in the simple lobule, increased their activity stepwise with each increase in tempo modulation from a steady beat. Neuronal populations in other parts of the posterior lobe showed an increase of activity only during the 20% condition, which involved conscious monitoring of rhythmic pattern synchronization, especially on the left side contralateral to the movements. Differential cerebellar activation patterns correspond to those in contralateral primary (primary sensorimotor), ipsilateral secondary (inferior parietal close to the intraparietal sulcus) and bilateral tertiary (dorsolateral prefrontal cortex) sensorimotor areas of the cerebral cortex, suggesting that distinct functional cortico-cerebellar circuits subserve differential aspects of rhythmic synchronization in regard to rhythmic motor control, conscious and subconscious response to temporal structure, and conscious monitoring of rhythmic pattern tracking.
我们使用正电子发射断层扫描（PET）研究了小脑在节律性听觉运动同步的时间控制的不同方面所起的作用。在5种条件下，受试者用右手食指随着节拍器的节奏敲击，平均频率为0.8赫兹：（1）等时节奏条件，（2）间隔持续时间随机变化，以及当节律性间隔的持续时间按照余弦波函数在（3）3%、（4）7%和（5）20%的基础间隔上进行连续时间调制时。无论运动同侧的蚓部和半球部分的节律时间结构如何，前叶小脑神经元群体在所有条件下均表现出相似的与运动相关的活动。双侧前后叶，尤其是简单小叶中的神经元群体，随着节奏调制从稳定节拍的每次增加而逐步增加其活动。后叶其他部分的神经元群体仅在20%的条件下表现出活动增加，这涉及对节律模式同步的有意识监测，尤其是在与运动对侧的左侧。小脑不同的激活模式与大脑皮层对侧初级（初级感觉运动）、同侧次级（靠近顶内沟的下顶叶）和双侧三级（背外侧前额叶皮层）感觉运动区域的激活模式相对应，这表明不同的功能性皮质 - 小脑回路在节律性运动控制、对时间结构的有意识和潜意识反应以及对节律模式跟踪的有意识监测方面，为节律同步的不同方面提供了支持。
