视觉空间工作记忆组间差异的神经机制

Neural Mechanisms of Group Differences in Visuospatial Working Memory

为考察视觉空间工作记忆(working memory,WM)维持和操作的组间差异及其神经机制,本研究记录了高、低WM组完成延迟再认(维持)任务和心理旋转(操作)任务时的行为和事件相关电位数据。结果发现,在操作任务中,高WM组比低WM组的反应时显著更短;高WM组的中前额叶慢波显著更正、双侧后顶区慢波显著更负,并且两者的波幅显著负相关。在维持任务中,两组被试的反应时无显著差异;高WM组的中前额叶慢波显著更正。结果表明,高WM组的执行注意能力可能更强,能通过有效调节和分配加工资源来表征视觉信息。

To investigate group differences in visuospatial working memory(WM)maintenance(low-execution)and manipulation(highexecution)and to clarify the neural mechanisms underpin them,the pair-wise task of delayed recognition task(maintenance)and mental rotation task(manipulation)were carried out on both low and high WM groups while event-related brain potentials were recorded.The results revealed that 1)a significant shorter response time(RT)was made by high WM group relative to low WM group in the manipulation task,and 2)a comparable RT were made by the two groups in the maintenance task.In the maintenance task,the high WM group showed significant larger positive slow waves in the middle frontal regions.In the manipulation task,the high WM group showed significant larger positive slow waves in the middle frontal regions and greater negative slow waves in the bilateral posterior parietal regions;moreover,a significant negative correlation was found between the slow-wave amplitudes in the middle frontal and bilateral posterior parietal regions.These findings indicate that a high WM group with strong executive attention may be expert in modulating and allocating processing resources.