Bishop Sonia J
Department of Psychology and Helen Wills Neuroscience Institute, Tolman Hall #1650, University of California Berkeley, Berkeley, California 94720-1650, USA.
Nat Neurosci. 2009 Jan;12(1):92-8. doi: 10.1038/nn.2242. Epub 2008 Dec 14.
Many neurocognitive models of anxiety emphasize the importance of a hyper-responsive threat-detection system centered on the amygdala, with recent accounts incorporating a role for prefrontal mechanisms in regulating attention to threat. Here we investigated whether trait anxiety is associated with a much broader dysregulation of attentional control. Volunteers performed a response-conflict task under conditions that posed high or low demands on attention. High trait-anxious individuals showed reduced prefrontal activity and slower target identification in response to processing competition when the task did not fully occupy attentional resources. The relationship between trait anxiety and prefrontal recruitment remained after controlling for state anxiety. These findings indicate that trait anxiety is linked to impoverished recruitment of prefrontal attentional control mechanisms to inhibit distractor processing even when threat-related stimuli are absent. Notably, this deficit was observed when ongoing task-related demands on attention were low, potentially explaining the day-to-day difficulties in concentration that are associated with clinical anxiety.
许多焦虑的神经认知模型强调以杏仁核为中心的过度反应性威胁检测系统的重要性,最近的研究认为前额叶机制在调节对威胁的注意力方面发挥作用。在这里,我们研究了特质焦虑是否与注意力控制的更广泛失调有关。志愿者们在对注意力要求高或低的条件下执行反应冲突任务。当任务没有完全占用注意力资源时,高特质焦虑个体在面对处理竞争时,前额叶活动减少,目标识别变慢。在控制状态焦虑后,特质焦虑与前额叶激活之间的关系依然存在。这些发现表明,即使在没有与威胁相关的刺激时,特质焦虑也与前额叶注意力控制机制的募集不足有关,从而难以抑制干扰物的处理。值得注意的是,当正在进行的与任务相关的注意力要求较低时,就会出现这种缺陷,这可能解释了与临床焦虑相关的日常注意力集中困难。