Nitchie Frederick, Casalvera Abigail, Teferi Marta, Patel Milan, Lynch Kevin, Makhoul Walid, Sheline Yvette, Balderston Nicholas L
medRxiv. 2023 Nov 12:2023.11.11.23298415. doi: 10.1101/2023.11.11.23298415.
Past research has shown that the bilateral dorsolateral prefrontal cortices (dlPFC) are implicated in both emotional processing as well as cognitive processing, in addition to working memory . Exactly how these disparate processes interact with one another within the dlPFC is less understood. To explore this, researchers designed an experiment that looked at working memory performance during fMRI under both emotional and non-emotional task conditions. Participants were asked to complete three tasks (letters, neutral images, emotional images) of the Sternberg Sorting Task under one of two trial conditions (sort or maintain). Regions of interest consisted of the left and right dlPFC as defined by brain masks based on NeuroSynth . Results showed a significant main effect of the 'sort' condition on reaction speed for all three trial types, as well as a main effect of task type (letters) on accuracy. In addition, a significant interaction was found between trial type (sort) and task type (letters), but not for either of the picture tasks. These results reveal a discrepancy between BOLD signal and behavioral data, with no significant difference in BOLD activity during image trials being displayed, despite longer response times for every condition. While these results show that the dlPFC is clearly implicated in non-emotional cognitive processing, more research is needed to explain the lack of BOLD activation seen here for similar emotionally valanced tasks, possibly indicating involvement of other brain networks.
以往的研究表明,双侧背外侧前额叶皮质(dlPFC)除了参与工作记忆外,还与情绪处理和认知处理有关。目前对于这些不同的过程在dlPFC内如何相互作用还知之甚少。为了探究这一点,研究人员设计了一项实验,观察在功能性磁共振成像(fMRI)下,情绪和非情绪任务条件下的工作记忆表现。参与者被要求在两种试验条件(分类或维持)之一的情况下完成斯特恩伯格分类任务的三项任务(字母、中性图像、情绪图像)。感兴趣的区域由基于NeuroSynth的脑图谱定义的左右dlPFC组成。结果显示,“分类”条件对所有三种试验类型的反应速度都有显著的主效应,任务类型(字母)对准确性也有主效应。此外,试验类型(分类)和任务类型(字母)之间存在显著的交互作用,但图片任务均未出现这种情况。这些结果揭示了血氧水平依赖(BOLD)信号与行为数据之间的差异,尽管每种条件下的反应时间更长,但在图像试验期间BOLD活动没有显著差异。虽然这些结果表明dlPFC显然与非情绪认知处理有关,但需要更多的研究来解释在此处类似情绪效价任务中未观察到BOLD激活的原因,这可能表明其他脑网络也参与其中。