Frontal lobe involvement in spatial span: Converging studies of normal and impaired function
Frontal lobe involvement in spatial span: Converging studies of normal and impaired function
复制标题
DOI：
10.1016/j.neuropsychologia.2005.05.010
复制
发表时间：
2006-01-01
期刊：
影响因子：
2.6
通讯作者：
Owen, AM
中科院分区：
文献类型：
--
作者：
Bor, D;Duncan, J;Owen, AM
虽然涉及前额叶皮层的猴子损伤研究通常报告工作记忆缺陷，神经成像研究一致表明前额叶参与此类任务，但该区域受损的患者通常不会显示任何工作记忆障碍。这种差异可能是由于对患者不敏感的测试措施，以及成像和患者研究中工作记忆任务之间的小而关键的差异。目前的研究使用了一种更敏感的空间工作记忆广度测量方法，该方法基于结构化或非结构化的空间阵列。一项针对正常受试者的PET研究证实，这两种变体确实激活了前额叶皮层。同样的任务被给予额叶患者和密切匹配的对照组。额叶大面积损伤的患者在这项任务中明显受损，右背外侧前额叶皮层受损的患者表现得特别受损。这一结果表明，前额叶皮层对于正常的工作记忆是必要的，即使是在简单的任务中，如空间跨度。然而，有人建议，病人赤字反映了战略或目标为基础的功能障碍，而不是存储限制。(c)2005爱思唯尔有限公司保留所有权利。
Although monkey lesion studies involving the prefrontal cortex commonly report working memory deficits, and neuroimaging studies consistently show prefrontal involvement in such tasks, patients with damage to this region commonly fail to show any working memory impairment. Such a discrepancy may be due to insensitive testing measures for patients, as well as small, yet critical differences between working memory tasks in imaging and patient studies. The current study utilised a more sensitive measure of spatial working memory spans, based either on structured or unstructured spatial arrays. A PET study in normal subjects confirmed that both variants did indeed activate prefrontal cortex. The same tasks were given to frontal lobe patients and closely matched controls. Patients with large frontal lesions were significantly impaired on this task, with those patients with damage to the right dorsolateral prefrontal cortex appearing particularly impaired. This result demonstrates that prefrontal cortex is necessary for normal working memory, even in simple tasks, such as spatial span. It is suggested, however, that the patient deficit reflects strategic or goal-based dysfunction, rather than storage limitations. (c) 2005 Elsevier Ltd. All rights reserved.