Program of Brain and Cognitive Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea.
Department of Brain and Cognitive Sciences, Seoul National University, Seoul, South Korea.
Hum Brain Mapp. 2024 Feb 1;45(2):e26619. doi: 10.1002/hbm.26619.
The prefrontal cortex (PFC) has been extensively studied in relation to various cognitive abilities, including executive function, attention, and memory. Nevertheless, there is a gap in our scientific knowledge regarding the functionally dissociable neural dynamics across the PFC during a cognitive task and their individual differences in performance. Here, we explored this possibility using a delayed match-to-sample (DMTS) working memory (WM) task using NIRSIT, a high-density, wireless, wearable functional near-infrared spectroscopy (fNIRS) system. First, upon presentation of the sample stimulus, we observed an immediate signal increase in the ventral (orbitofrontal) region of the anterior PFC, followed by activity in the dorsolateral PFC. After the DMTS test stimulus appeared, the orbitofrontal cortex activated once again, while the rest of the PFC showed overall disengagement. Individuals with higher accuracy showed earlier and sustained activation of the PFC across the trial. Furthermore, higher network efficiency and functional connectivity in the PFC were correlated with individual WM performance. Our study sheds new light on the dynamics of PFC subregional activity during a cognitive task and its potential applicability in explaining individual differences in experimental, educational, or clinical populations. PRACTITIONER POINTS: Wearable functional near-infrared spectroscopy (fNIRS) captured dissociable temporal dynamics across prefrontal subregions during a delayed match-to-sample task. Anterior regions of the orbitofrontal cortex (OFC) activated first during the delay period, followed by the dorsolateral prefrontal cortex (PFC). PFC disengaged overall after the delay, but the OFC reactivated to the test stimulus. Earlier and sustained activation of PFC was associated with better accuracy. Functional connectivity and network efficiency also varied with task performance.
前额叶皮层（PFC）在各种认知能力的研究中得到了广泛的研究，包括执行功能、注意力和记忆力。然而，我们在科学知识方面还存在差距，即关于认知任务期间 PFC 中功能可分离的神经动力学及其在性能方面的个体差异。在这里，我们使用 NIRSIT 探索了这种可能性，NIRSIT 是一种高密度、无线、可穿戴的功能性近红外光谱（fNIRS）系统。首先，在呈现样本刺激时，我们观察到腹侧（眶额）前 PFC 区域的信号立即增加，然后是背外侧 PFC 的活动。在 DMTS 测试刺激出现后，眶额皮层再次激活，而其余的 PFC 则总体上脱机。准确性较高的个体在整个试验中表现出更早和持续的 PFC 激活。此外，PFC 中的网络效率和功能连接更高与个体 WM 表现相关。我们的研究为认知任务期间 PFC 亚区活动的动力学及其在解释实验、教育或临床人群中的个体差异方面的潜在适用性提供了新的视角。从业者要点：可穿戴式功能性近红外光谱（fNIRS）在延迟匹配样本任务中捕获了前额叶亚区之间可分离的时间动态。眶额皮层（OFC）的前区域在延迟期间首先激活，然后是背外侧前额叶皮层（PFC）。PFC 在延迟后总体脱机，但 OFC 重新激活到测试刺激。PFC 的早期和持续激活与更好的准确性相关。功能连接和网络效率也随任务表现而变化。
