Tsujimoto Satoshi, Yamamoto Tsuyoshi, Kawaguchi Hideo, Koizumi Hideaki, Sawaguchi Toshiyuki
Laboratory of Cognitive Neurobiology, Hokkaido University Graduate School of Medicine, Kita-ku, Sapporo 060-8638, Japan.
Cereb Cortex. 2004 Jul;14(7):703-12. doi: 10.1093/cercor/bhh030. Epub 2004 Apr 14.
It is well known that lateral areas of the prefrontal cortex (LPFC) play a central role in working memory (a critical basis of various cognitive functions), but it remains unknown whether the LPFC of children of preschool age is responsible for working memory. To address this issue, we adopted a recently developed non-invasive imaging technique, optical topography (OT), which can potentially be applied to functional mapping in childhood. We firstly examined changes of activity in the LPFC using OT while adult subjects performed an item-recognition task, which requires working memory, under different memory-load conditions. We observed activation in the bilateral LPFC during performance of this task, the magnitude of which differed depending on memory-load. Then, we applied the same technique on 5- and 6-year-old children and observed the activation associated with working memory in the LPFC. Areas and properties of such activity were similar in adults and preschool children. Thus, for the first time, we demonstrate that the LPFC of preschoolers is active during working memory processes, indicating that in 5- and 6-year-old children, the LPFC has already developed processing of this important cognitive function.
众所周知，前额叶皮质的外侧区域（LPFC）在工作记忆（各种认知功能的关键基础）中起着核心作用，但学龄前儿童的LPFC是否负责工作记忆仍不清楚。为了解决这个问题，我们采用了一种最近开发的非侵入性成像技术，光学地形图（OT），它有可能应用于儿童的功能映射。我们首先在成年受试者执行一项需要工作记忆的项目识别任务时，使用OT检查LPFC中的活动变化，该任务在不同的记忆负荷条件下进行。我们观察到在执行此任务期间双侧LPFC的激活，其幅度因记忆负荷而异。然后，我们对5岁和6岁的儿童应用相同的技术，并观察到LPFC中与工作记忆相关的激活。这种活动的区域和特性在成年人和学龄前儿童中相似。因此，我们首次证明学龄前儿童的LPFC在工作记忆过程中是活跃的，这表明在5岁和6岁的儿童中，LPFC已经发展出对这种重要认知功能的处理能力。
