An fMRI investigation of cortical contributions to spatial and nonspatial visual working memory
An fMRI investigation of cortical contributions to spatial and nonspatial visual working memory
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DOI：
10.1006/nimg.2000.0570
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发表时间：
2000-05-01
期刊：
影响因子：
5.7
通讯作者：
Corkin, S
中科院分区：
文献类型：
--
作者：
Postle, BR;Stern, CE;Corkin, S
本报告中提出的实验旨在检验以下假设：空间刺激和物体刺激的视觉工作记忆在前额皮质中招募单独的神经元网络。我们从受试者那里获取了大胆的功能磁共振成像数据，同时他们将每个连续呈现的刺激与之前出现过两到三个刺激的刺激进行比较。三个实验未能拒绝零假设，即与空间工作记忆表现相关的前额皮质活动不能与与非空间工作记忆表现相关的前额皮质活动分开。顶叶皮质的多模态区域（顶下小叶和上顶叶）以及额上沟周围的皮质（并包围额叶眼野）也表现出在空间和物体条件下的同等激活水平。然而，与腹侧视觉处理流相关的后皮质区域（舌回、梭状回和颞下回的部分）表现出比空间工作记忆相关活动更大的物体，特别是当刺激仅沿空间或特征维度变化时。这些实验代表了空间和物体工作记忆的功能磁共振成像研究，其中测试程序和刺激在两种条件下是相同的，表明特定领域的视觉工作记忆处理可能是由与特定领域的感觉处理相关的后部区域介导的。 (C) 2000 年学术出版社。
The experiments presented in this report were designed to test the hypothesis that visual working memory for spatial stimuli and for object stimuli recruits separate neuronal networks in prefrontal cortex. We acquired BOLD fMRI data from subjects while they compared each serially presented stimulus to the one that had appeared two or three stimuli previously. Three experiments failed to reject the null hypothesis that prefrontal cortical activity associated with spatial working memory performance cannot be dissociated from prefrontal cortical activity associated with nonspatial working memory performance. Polymodal regions of parietal cortex (inferior and superior parietal lobules), as well as cortex surrounding the superior frontal sulcus (and encompassing the frontal eye fields), also demonstrated equivalent levels of activation in the spatial and object conditions. Posterior cortical regions associated with the ventral visual processing stream (portions of lingual, fusiform, and inferior temporal gyri), however, demonstrated greater object than spatial working memory-related activity, particularly when stimuli varied only along spatial or featural dimensions. These experiments, representing fMRI studies of spatial and object working memory in which the testing procedure and the stimuli were identical in the two conditions, suggest that domain-specific visual working memory processing may be mediated by posterior regions associated with domain-specific sensory processing. (C) 2000 Academic Press.