研究人员发现，岛叶皮层作为恐惧的状态依赖性调节器，对于建立小鼠恐惧记忆的消除和维持之间的平衡是必要的。虽然岛叶皮层对恐惧线索的反应性随其预测伤害的确定性而增加，但这种活动通过身体的负反馈而减弱，这种反馈产生于僵住期间的心率减速。通过迷走神经刺激扰乱了身体-大脑的交流，破坏了类似于岛叶皮层抑制的恐惧消除和维持之间的平衡。
这些数据显示，岛叶皮层整合了预测性的感觉和互感信号，从而提供分级和双向的指导信号，为恐惧的消除把关，并说明身体反馈信号如何被用来在功能平衡中维持恐惧。
据悉，大脑如何将恐惧维持在一个适应的范围内仍未知。
附：英文原文
Title: Fear balance is maintained by bodily feedback to the insular cortex in mice
Author: Alexandra S. Klein, Nate Dolensek, Caroline Weiand, Nadine Gogolla
Issue&Volume: 2021-11-19
Abstract: How does the brain maintain fear within an adaptive range We found that the insular cortex acts as a state-dependent regulator of fear that is necessary to establish an equilibrium between the extinction and maintenance of fear memories in mice. Whereas insular cortex responsiveness to fear-evoking cues increased with their certainty to predict harm, this activity was attenuated through negative bodily feedback that arose from heart rate decelerations during freezing. Perturbation of body-brain communication by vagus nerve stimulation disrupted the balance between fear extinction and maintenance similar to insular cortex inhibition. Our data reveal that the insular cortex integrates predictive sensory and interoceptive signals to provide graded and bidirectional teaching signals that gate fear extinction and illustrate how bodily feedback signals are used to maintain fear within a functional equilibrium.
DOI: abj8817
Source: https://www.science.org/doi/10.1126/science.abj8817