Owen A M, Evans A C, Petrides M
Montreal Neurological Institute, McGill University, Montreal, Canada.
Cereb Cortex. 1996 Jan-Feb;6(1):31-8. doi: 10.1093/cercor/6.1.31.
Previous work in nonhuman primates and in patients with frontal lobe damage has suggested that the frontal cortex plays a critical role in the performance of both spatial and nonspatial working memory tasks. The present study used positron emission tomography with magnetic resonance imaging to demonstrate the existence, within the human brain, of two functionally distinct subdivisions of the lateral frontal cortex, which may subserve different aspects of spatial working memory. Five spatial memory tasks were used, which varied in terms of the extent to which they required different executive processes. When the task required the organization and execution of a sequence of spatial moves retained in working memory, significant changes in blood flow were observed in ventrolateral frontal cortex (area 47) bi-laterally. By contrast, when the task required active monitoring and manipulation of spatial information within working memory, additional activation foci were observed in mid-dorsolateral frontal cortex (areas 46 and 9). These findings support a two-stage model of spatial working memory processing within the lateral frontal cortex.
先前对非人类灵长类动物和额叶损伤患者的研究表明，额叶皮质在空间和非空间工作记忆任务的执行中起着关键作用。本研究使用正电子发射断层扫描结合磁共振成像，以证明在人类大脑中存在外侧额叶皮质的两个功能不同的细分区域，它们可能服务于空间工作记忆的不同方面。使用了五项空间记忆任务，这些任务在所需不同执行过程的程度上有所不同。当任务需要组织和执行保留在工作记忆中的一系列空间移动时，双侧腹外侧额叶皮质（47区）的血流出现了显著变化。相比之下，当任务需要在工作记忆中对空间信息进行主动监测和操作时，在背外侧额叶皮质中部（46区和9区）观察到了额外的激活灶。这些发现支持了外侧额叶皮质内空间工作记忆处理的两阶段模型。
