Department of Clinical Neuroscience and Psychiatry, Osaka University Graduate School of Medicine, D3 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
Behav Brain Res. 2010 Dec 20;215(1):21-7. doi: 10.1016/j.bbr.2010.06.016. Epub 2010 Jun 19.
Although visuospatial working memory (VSWM) is commonly used during speeded and unconscious memory processing in daily life, most neuroimaging studies on VSWM use tasks that impose motor restrictions onto the examinees to avoid movement-related artifacts. Multichannel near-infrared spectroscopy (NIRS), however, can measure cortical activation during cognitive processing without interfering with task procedure. The purpose of this study is to determine whether multichannel NIRS can detect VSWM-induced frontal cortex activation similar to that seen in VSWM performance in daily-life activity. Using NIRS, we measured relative changes in the concentration of oxygenated hemoglobin as an index of frontal activation in 52 measurement points (channels) on the frontal area during the Advanced Trail Making Test (ATMT), a tool used to assess VSWM. The ATMT consists of two tasks, R and F, with the former assessing motor factors and the latter relating to both motor and cognitive factors involved in speeded and unconscious VSWM operations. Twenty-six healthy volunteers were enrolled in this study. Channel activation during Task F performance was observed bilaterally over the dorsolateral and ventrolateral prefrontal cortex. This distribution may reflect central executive function of working memory. Channel activation during Task R was circumscribed to part of the left ventrolateral prefrontal cortex partially overlapping with areas active during Task F performance, likely representing task-related motor factor activation. Our findings suggest that multichannel NIRS during ATMT performance is an appropriate means of measuring cortical activation induced by VSWM operations during daily activity.
虽然视空间工作记忆（VSWM）在日常生活中的快速和无意识记忆处理中经常被使用，但大多数关于 VSWM 的神经影像学研究使用的任务都对被试者施加了运动限制，以避免与运动相关的伪影。然而，多通道近红外光谱（NIRS）可以在不干扰任务过程的情况下测量认知处理期间的皮质激活。本研究的目的是确定多通道 NIRS 是否可以检测到与日常生活活动中的 VSWM 表现相似的 VSWM 诱导的额皮质激活。使用 NIRS，我们在额区的 52 个测量点（通道）上测量了含氧血红蛋白浓度的相对变化，作为额激活的指标，在高级追踪测试（ATMT）期间进行。ATMT 由两个任务 R 和 F 组成，前者评估运动因素，后者涉及与快速和无意识 VSWM 操作相关的运动和认知因素。本研究纳入了 26 名健康志愿者。在执行任务 F 期间，双侧观察到背外侧和腹外侧前额皮质的通道激活。这种分布可能反映了工作记忆的中央执行功能。在执行任务 R 期间，通道激活局限于左侧腹外侧前额皮质的一部分，部分与执行任务 F 时的活跃区域重叠，可能代表与任务相关的运动因素激活。我们的研究结果表明，在 ATMT 执行过程中使用多通道 NIRS 是测量日常生活活动中 VSWM 操作引起的皮质激活的一种合适方法。
