Sadato N, Campbell G, Ibáñez V, Deiber M, Hallett M
Human Motor Control Section, Medical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892-1428, USA.
J Neurosci. 1996 Apr 15;16(8):2691-700. doi: 10.1523/JNEUROSCI.16-08-02691.1996.
Brain regions activated with complex sequential finger movements were localized by measuring regional cerebral blood flow (rCBF) with positron emission tomography. Whereas the total number and frequency of finger movements were kept constant, the complexity of auditory cued sequential finger movements of the right hand varied, with sequence length as the independent variable. In four conditions of differing complexity, the bilateral primary sensorimotor area, left ventral premotor cortex, posterior supplementary motor area, right superior part of the cerebellum, and left putamen were consistently and equally activated. This finding suggests an executive role in running sequences, regardless of their length. The right dorsal premotor cortex (Brodmann area 6) and the right precuneus (Brodmann area 7) showed a linear increase of rCBF as sequence complexity increased. This finding is consistent with the hypothesis that these areas function in the storage of motor sequences in spatial working memory and the production of ongoing sequential movement with reference to that of buffered memory. A similar increase in the cerebellar vermis and the left thalamus likewise suggests a role of these subcortical structures in complexity of sequential finger movements. Conversely, the left inferior parietal lobule showed a decrease of rCBF as complexity increased. Because short-term phonological storage is localized to this area, we suggest that the visuospatial working memory system may suppress other systems not in use. Our findings suggest that complex sequential finger movements recruit a discrete set of brain areas, in addition to areas underlying the execution of simple movement sequences.
通过正电子发射断层扫描测量局部脑血流量（rCBF），来定位因复杂连续手指运动而激活的脑区。虽然手指运动的总数和频率保持不变，但右手听觉提示的连续手指运动的复杂性有所不同，以序列长度作为自变量。在四种不同复杂程度的条件下，双侧初级感觉运动区、左侧腹侧运动前区、后部辅助运动区、小脑右侧上部以及左侧壳核均持续且同等程度地被激活。这一发现表明，无论序列长度如何，这些脑区在执行序列方面发挥着作用。随着序列复杂性的增加，右侧背侧运动前区（布罗德曼第6区）和右侧楔前叶（布罗德曼第7区）的rCBF呈线性增加。这一发现与以下假设一致，即这些区域在空间工作记忆中存储运动序列，并参照缓冲记忆产生正在进行的连续运动。小脑蚓部和左侧丘脑的类似增加同样表明这些皮质下结构在连续手指运动的复杂性方面发挥作用。相反，随着复杂性增加，左侧顶下小叶的rCBF减少。由于短期语音存储定位于该区域，我们认为视觉空间工作记忆系统可能会抑制其他未使用的系统。我们的研究结果表明，除了执行简单运动序列的脑区外，复杂的连续手指运动还会激活一组离散的脑区。
