NIMH Center for the Study of Emotion and Attention, University of Florida, Gainesville, FL 32608, USA.
Neuropsychologia. 2010 Oct;48(12):3580-4. doi: 10.1016/j.neuropsychologia.2010.08.007. Epub 2010 Aug 14.
We tested whether visual cortical sensitivity to external cues in the context of an acute defensive reaction is heightened or attenuated. A strong cardiac defense (fear) response was elicited by presenting an abrupt, loud acoustic stimulus following a 10-min period of quiescence. Electrocortical responses to aversive and neutral pictures following defensive stimulus onset were measured using dense-array EEG. Pictures were flickered at 12.5 Hz to evoke steady-state visual evoked potentials (ssVEP), which can be reliably extracted on the basis of single trials. Visual cortical activity indexing perceptual processing was substantially heightened when pictures were shown in temporal proximity to (i.e., 5s after) the defense stimulus. Replicating previous studies, aversive visual stimuli were associated with enhanced ssVEP amplitude, compared to neutral stimuli. Acute defense facilitates visual perception of external cues and preserves accurate discrimination between threatening and safe cues.
我们测试了在急性防御反应的背景下，对外界线索的视觉皮层敏感性是增强还是减弱。在安静 10 分钟后，突然发出响亮的声音刺激，会引发强烈的心脏防御（恐惧）反应。使用密集型 EEG 测量防御性刺激开始后对厌恶和中性图片的脑电反应。通过闪烁图片以 12.5 Hz 的频率来引发稳态视觉诱发电位（ssVEP），可以基于单次试验可靠地提取。当图片在时间上接近（即防御刺激后 5 秒）时显示时，视觉皮层活动指示感知处理大大增强。与之前的研究一致，与中性刺激相比，厌恶视觉刺激与增强的 ssVEP 幅度相关。急性防御促进对外界线索的视觉感知，并保持对威胁和安全线索的准确区分。
