Numata Kenji, Nakajima Yoshio, Shibata Tadahiko, Shimizu Shinobu
Department of Physical Therapeutics, College of Medical Sciences, Showa University, 1865 Tokaichiba-machi, Midori-ku, Yokohama 226-8555, Japan.
Department of Physiology, School of Medicine Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-0856, Japan.
J Jpn Phys Ther Assoc. 2002;5(1):1-5. doi: 10.1298/jjpta.5.1.
From the viewpoint of psychology, it is thought that perception analysis of the visual world includes two information processes: global (whole) and local (part) processes. It is assumed that the global process is carried out in the right hemisphere, and the local process, in the left hemisphere. In the present study, gamma EEG band activities during location memory (LM) task, as a global form, and shape memory (SM) task, as a local form, were calculated from the temporal, parietal and occipital areas using stimuli consisting of categorical patterns of small shapes. Gamma band activity during the SM task was greater than that during the LM task. It was assumed that the SM task requires a higher memory load condition than the LM task. In terms of the laterality ratio obtained from the whole electrode array, the gamma band was significantly activated in the right hemisphere during the LM task, and in the left hemisphere during the SM task. The gamma activation in the occipital area was significantly high in the right hemisphere for both tasks. High gamma band activation was observed in the right parietal area during the LM task and in the left temporal area during the SM task. It was concluded that global and local information processes occur in the left temporal areas and in the right occipitoparietal areas, respectively. The results of this study are useful in the assessment of visual cognition deficits in patients with cerebral hemispheric lesions in the physical therapy.
从心理学角度来看，人们认为对视觉世界的感知分析包括两个信息处理过程：全局（整体）和局部（部分）过程。据推测，全局过程在右半球进行，而局部过程在左半球进行。在本研究中，使用由小形状的分类模式组成的刺激，从颞叶、顶叶和枕叶区域计算位置记忆（LM）任务（作为一种全局形式）和形状记忆（SM）任务（作为一种局部形式）期间的伽马脑电图频段活动。SM任务期间的伽马频段活动大于LM任务期间的。据推测，SM任务比LM任务需要更高的记忆负荷条件。就从整个电极阵列获得的偏侧化比率而言，在LM任务期间右半球的伽马频段显著激活，而在SM任务期间左半球的伽马频段显著激活。在两项任务中，枕叶区域右半球的伽马激活均显著较高。在LM任务期间右顶叶区域观察到高伽马频段激活，在SM任务期间左颞叶区域观察到高伽马频段激活。得出的结论是，全局和局部信息处理分别发生在左颞叶区域和右枕顶叶区域。本研究结果有助于在物理治疗中评估脑半球病变患者的视觉认知缺陷。
