Anxiety and cognitive efficiency: Differential modulation of transient and sustained neural activity during a working memory task
Anxiety and cognitive efficiency: Differential modulation of transient and sustained neural activity during a working memory task
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DOI：
10.3758/cabn.8.3.239
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发表时间：
2008-09-01
影响因子：
2.9
通讯作者：
Braver, T. S.
中科院分区：
文献类型：
--
作者：
Fales, C. L.;Barch, D. M.;Braver, T. S.
根据加工效率假说（Eysenck, Derakshan, Santos, & Calvin, 2007），焦虑个体被认为需要更大程度地激活支持认知控制的大脑系统（例如，背外侧前额叶皮层；DLPFC），以保持与非焦虑受试者相同的表现。最近的一项认知控制理论（Braver, Gray, & Burgess, 2007）提出，认知效率的降低可能是DLPFC招募的时间动态变化的结果。在这项研究中，我们使用了一个混合的阻塞/事件相关的fMRI设计来跟踪高焦虑和低焦虑参与者在执行工作记忆任务时DLPFC的短暂和持续活动。这项任务是在参与者观看了旨在诱导中性或焦虑相关情绪的视频后进行的。在观看中性视频后，与低焦虑的参与者相比，高焦虑的参与者在工作记忆区域的持续激活减少，但瞬态激活增加。高焦虑组的“默认网络”区域的持续激活也大幅减少（可能失活）。在观看负面视频后，低焦虑组的认知控制区域的激活动态与高焦虑组相似。这些结果表明，焦虑中认知控制的减少可能是由于短暂的，而不是持续的工作记忆招募模式。本研究的补充信息可在www.psychonomic.org/archive上找到。
According to the processing-efficiency hypothesis (Eysenck, Derakshan, Santos, & Calvin, 2007), anxious individuals are thought to require greater activation of brain systems supporting cognitive control (e.g., dorsolateral prefrontal cortex; DLPFC) in order to maintain equivalent performance to nonanxious subjects. A recent theory of cognitive control (Braver, Gray, & Burgess, 2007) has proposed that reduced cognitive efficiency might occur as a result of changes in the temporal dynamics of DLPFC recruitment. In this study, we used a mixed blocked/event-related fMRI design to track transient and sustained activity in DLPFC while high- and low-anxious participants performed a working memory task. The task was performed after the participants viewed videos designed to induce neutral or anxiety-related moods. After the neutral video, the high-anxious participants had reduced sustained but increased transient activation in working memory areas, in comparison with low-anxious participants. The high-anxious group also showed extensive reductions in sustained activation of "default-network" areas (possible deactivation). After the negative video, the low-anxiety group shifted their activation dynamics in cognitive control regions to resemble those of the high-anxious group. These results suggest that reduced cognitive control in anxiety might be due to a transient, rather than sustained, pattern of working memory recruitment. Supplementary information for this study may be found at www.psychonomic.org/archive.