Ross P, Segalowitz S J
University of Waterloo, Ontario, Canada.
Brain Cogn. 2000 Jun-Aug;43(1-3):375-9.
We examined Goldman-Rakic's conceptualization of working memory (WM) involving modality-specific reverbatory circuits using electrophysiological measures. An n-back WM task, with either spatial information or object information to be remembered, was administered with EEG coherence used to provide a functional measure of corticocortical communication. Support was not found for modality-specific WM systems in this task. Instead, results suggest that there is a circuit that connects dorsal frontal with dorsal parietal areas which is activated during all levels of the WM vigilance task, regardless of the type of stimuli involved. Data also suggest that left frontal areas are sensitive to the level of difficulty of the WM task (0,1,2, and 3-back), as well as familiarity of task demands. Overall, our results support a model that conceptualizes a unitary WM system rather than a system composed of separate WM circuits for different modalities.
我们使用电生理测量方法，研究了戈德曼-拉基奇关于工作记忆（WM）的概念，即涉及特定感觉模态的回响回路。我们实施了一个n-back工作记忆任务，其中要记忆空间信息或物体信息，并使用脑电图相干性来提供皮质-皮质通信的功能测量。在这项任务中未发现支持特定感觉模态工作记忆系统的证据。相反，结果表明存在一个连接背侧额叶和背侧顶叶区域的回路，该回路在工作记忆警觉任务的所有水平上都会被激活，而与所涉及的刺激类型无关。数据还表明，左额叶区域对工作记忆任务的难度水平（0、1、2和3-back）以及任务要求的熟悉程度敏感。总体而言，我们的结果支持一种将工作记忆系统概念化为单一系统的模型，而不是由针对不同感觉模态的单独工作记忆回路组成的系统。
