Opposing influences of emotional and non-emotional distracters upon sustained prefrontal cortex activity during a delayed-response working memory task
Opposing influences of emotional and non-emotional distracters upon sustained prefrontal cortex activity during a delayed-response working memory task
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DOI：
10.1016/j.neuropsychologia.2007.07.010
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发表时间：
2008-01-01
期刊：
影响因子：
2.6
通讯作者：
McCarthy, Gregory
中科院分区：
文献类型：
--
作者：
Dolcos, Florin;Diaz-Granados, Paul;McCarthy, Gregory
延迟反应工作记忆（WM）任务的表现通常与背外侧前额叶皮层（dlPFC）的持续激活有关，该激活跨越了记忆和记忆探针之间的延迟。最近的研究表明，在延迟期间出现的新干扰物既会影响持续激活，也会损害WM的表现。然而，表现障碍干扰物对持续延迟活动的影响与干扰物的特征有关：可混淆的备忘录干扰物增加延迟活动，而非可混淆的备忘录情绪干扰物减少延迟活动。因为这些不同的影响是在不同的研究中观察到的，所以有可能涉及不同的dlPFC区域，这种悖论是表面上的，而不是真实的。为了研究这种可能性，在受试者执行WM任务时，记录了与事件相关的fMRI数据，这些任务在延迟间隔内出现了可混淆的（新面孔）和不可混淆的（新场景）情绪干扰物。与之前的研究结果一致，可混淆的面孔干扰物增加了dlPFC延迟活动，而不可混淆的情绪干扰物减少了dlPFC延迟活动，这些相反的影响调节了同一dlPFC区域的活动。这些结果提供了直接的证据，表明dlPFC的特定区域通常参与了分散注意力的调节作用，同时对分散注意力的性质表现出敏感性。这些发现有助于理解与认知控制的一般损伤和控制情绪分心能力的特定损伤相关的神经机制的改变，例如分别在衰老和情感障碍中观察到的变化。(c) 2007年Elsevier Ltd.出版
Performance in delayed-response working memory (WM) tasks is typically associated with sustained activation in the dorsolateral prefrontal cortex (dlPFC) that spans the delay between the memoranda and the memory probe. Recent studies have demonstrated that novel distracters presented during the delay interval both affect sustained activation and impair WM performance. However, the effect of the performance-impairing distracters upon sustained dlPFC delay activity was related to the characteristics of the distracters: memoranda-confusable distracters increased delay activity, whereas memoranda-nonconfusable emotional distracters decreased delay activity. Because these different effects were observed in different studies, it is possible that different dlPFC regions were involved and the paradox is more apparent than real. To investigate this possibility, event-related fMRI data were recorded while subjects performed a WM task for faces with memoranda-confusable (novel faces) and memoranda-nonconfusable emotional (novel scenes) distracters presented during the delay interval. Consistent with previous findings, confusable face distracters increased dlPFC delay activity, while nonconfusable emotional distracters decreased dlPFC delay activity, and these opposing effects modulated activity in the same dlPFC regions. These results provide direct evidence that specific regions of the dlPFC are generally involved in mediating the effects of distraction, while showing sensitivity to the nature of distraction. These findings are relevant for understanding alterations in the neural mechanisms associated with both general impairment of cognitive control and with specific impairment in the ability to control emotional distraction, such as those observed in aging and affective disorders, respectively. (c) 2007 Published by Elsevier Ltd.