Department of Psychiatry, Oxford University, Oxford, UK.
Neuroimage. 2012 Jan 16;59(2):1942-8. doi: 10.1016/j.neuroimage.2011.09.007. Epub 2011 Sep 16.
Attention is preferentially deployed toward those stimuli which are threatening and those which are surprising. The current paper examines the intersection of these phenomena; how do expectations about the threatening nature of stimuli influence the deployment of attention? The predictions tested were that individuals would direct attention toward stimuli which were expected to be threatening (regardless of whether they were or not) and toward stimuli which were surprising. As anxiety has been associated with deficient control of attention to threat, it was additionally predicted that high levels of trait anxiety would be associated with deficits in the use of threat-expectation to guide attention. During fMRI scanning, 29 healthy volunteers completed a simple task in which threat-expectation was manipulated by altering the frequency with which fearful or neutral faces were presented. Individual estimates of threat-expectation and surprise were created using a Bayesian computational model. The degree to which the model derived estimates of threat-expectation and surprise were able to explain both a behavioral measure of attention to the faces and activity in the visual cortex and anterior attentional control areas was then tested. As predicted, increased threat-expectation and surprise were associated with increases in both the behavioral and neuroimaging measures of attention to the faces. Additionally, regions of the orbitofrontal cortex and left amygdala were found to covary with threat-expectation whereas anterior cingulate and lateral prefrontal cortices covaried with surprise. Individuals with higher levels of trait anxiety were less able to modify neuroimaging measures of attention in response to threat-expectation. These results suggest that continuously calculated estimates of the probability of threat may plausibly be used to influence the deployment of visual attention and that use of this information is perturbed in anxious individuals.
注意优先分配给那些具有威胁性和令人惊讶的刺激。本文研究了这两种现象的交集；对于刺激的威胁性的期望如何影响注意力的分配？测试的预测是，个体将注意力集中在预期具有威胁性的刺激上（无论它们是否具有威胁性），并集中在令人惊讶的刺激上。由于焦虑与对威胁的注意力控制不足有关，因此还预测高水平的特质焦虑与使用威胁预期来指导注意力的缺陷有关。在 fMRI 扫描过程中，29 名健康志愿者完成了一项简单的任务，通过改变呈现恐惧或中性面孔的频率来操纵威胁预期。使用贝叶斯计算模型创建了个体对威胁预期和惊讶的估计。然后测试该模型对视觉皮层和前注意控制区域的面孔注意力的行为测量和活动的解释程度，以及模型对威胁预期和惊讶的估计程度。正如预测的那样，增加威胁预期和惊讶与行为和神经影像学测量的面孔注意力都增加了。此外，发现眶额皮层和左侧杏仁核与威胁预期相关，而前扣带皮层和外侧前额叶皮层与惊讶相关。特质焦虑水平较高的个体在响应威胁预期时，对神经影像学注意力测量的调整能力较差。这些结果表明，不断计算的威胁概率估计可能合理地用于影响视觉注意力的分配，并且在焦虑个体中，这种信息的使用受到干扰。
Zotero 插件
