中文摘要：

目的工作记忆是重要的认知功能之一。研究工作记忆任务中多通道脑电（multi—channel，EEGs）在各个频率范围的能量分布，可为研究工作记忆的特征频段和关键脑区提供支持。方法记录健康受试者在视觉工作记忆任务中的32通道EEGs，共16例受试者240次实验数据；对原始EEGs进行预处理；应用傅里叶变换计算预处理后的EECs在δ、θ、α、β、γ频段能量的空间分布和各个频段能量占总能量的百分比。结果8、0、仅、13、1频段能量占总能量的百分比分别为（22．44±0．86）％、（31．88±0．55）％、（24．66±1．43）％、（13．54±0．64）％、（7．47±0．48）％，θ频段的能量显著高于其他频段的能量，差异具有统计学意义（P〈0．001）；在θ频段，能量主要集中于额中线区。结论θ频段是工作记忆的特征频段，额区是工作记忆的关键脑区。

英文摘要：

Objective Working memory （WM） is one of important cognitive functions. The aim of this study was to investigate spatial distributions of electroencephalographs （EEGs） power during visual WM task, which may provide support for studying the principal frequency band and critical region related to WM. Methods 32-channel EEGs were recorded from 16 healthy subjects while they perform visual WM task. The data came from 240 trials and the original EEGs were preprocessed. Fourier transform was applied to calculate spatial distributions of EEGs power in the δ,θ,α, β, γ frequency bands and the percentage of each band in the total power. Results The percentages of δ,θ,α, β, γ bands in the total power were （22.44±0.86）%, （31.88±0.55）%, （24.66±1.43）%, （13.54±0.64）%, （7.47± 0.48）%, respectively. The power in the θ band was significantly higher than those in the other bands （paired t-test, P〈0.001）. The θ power was focused in the frontal midline region. Conclusions The principal frequency band related to WM was the θ band and the critical region was the frontal region.