对特定事物的恐惧涉及恐惧调节过程中几个环节的异常，就是个起承转合的过程，当恐惧建立后就是恐惧的巩固，再来是恐惧的消退，恐惧消退的维持，以及恐惧的恢复和更新。主要有以下几个过程：
恐惧的形成过程依赖于杏仁核和海马、vmPFC、dlPFC之间的连接。可能由于疼痛、不愉快的情绪等多种因素导致。但是形成归形成，后面还依赖很长一串过程的。
Tzschoppe J, Nees F, Banaschewski T, Barker GJ, Buchel C, Conrod PJ et al (2014). Aversive learning in adolescents: modulation by amygdala-prefrontal and amygdala-hippocampal connectivity and neuroticism. Neuropsychopharmacology 39: 875–884.
恐惧的巩固：依靠杏仁核到dacc以及海马到岛叶功能连通性的增强，以及杏仁核到内侧前额叶皮层功能连接的减少。
Feng P, Feng T, Chen Z, Lei X (2014). Memory consolidation of fear conditioning: bi-stable amygdala connectivity with dorsal anterior cingulate and medial prefrontal cortex. Soc Cogn Affect Neurosci 9: 1730–1737.
恐惧的消除：消退学习（extinction learning）杏仁核也激活了。这时候如果杏仁核不灵了那就只能继续怕着了啊！！！但是腹内侧前额叶皮层在恐惧消退过程的启动和巩固是灰常灰常重要的！！！灰质薄的人也容易感到害怕啊！！！而且在恐惧消退阶段还有抑制条件反射的重要作用！！！
Linnman C, Zeidan MA, Pitman RK, Milad MR (2012). Resting cerebral metabolism correlates with skin conductance and functional brain activation during fear conditioning. Biol Psychol 89: 450–459.
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Phelps EA, Delgado MR, Nearing KI, LeDoux JE (2004). Extinction learning in humans: role of the amygdala and vmPFC. Neuron 43: 897–905.
此外REM睡眠在恐惧消退中也很重要！！！REM睡眠简直就是玄学啊！！！剥夺REM睡眠导致早期消退保持期间的皮肤电导增加，以及左中颞回的激活。
Spoormaker VI, Schroter MS, Andrade KC, Dresler M, Kiem SA, Goya-Maldonado R et al (2012). Effects of rapid eye movement sleep deprivation on fear extinction recall and prediction error signaling. Hum Brain Mapp 33: 2362–2376.
此外恐惧消退期间还要靠双侧岛叶、扣带回和楔前叶的激活啊！！！不灵了继续怕着啊！！！
Garfinkel SN, Abelson JL, King AP, Sripada RK, Wang X, Gaines LM et al (2014). Impaired contextual modulation of memories in PTSD: an fMRI and psychophysiological study of extinction retention and fear renewal. J Neurosci 34: 13435–13443.
最后就是恐惧恢复的过程了，劳资明明没什么感觉了，怎么今天看到突然又怕了啊！！！一个是和内脏刺激有关的恐惧，在恢复期间观察到海马旁皮质和后扣带皮层明显的激活！！在条件刺激下海马和丘脑的激活似乎就是恐惧的元凶啊，海马萎缩了条件反射也没了啊！！哎哟！！
Gramsch C, Kattoor J, Icenhour A, Forsting M, Schedlowski M, Gizewski ER et al (2014). Learning pain-related fear: neural mechanisms mediating rapid differential conditioning, extinction and reinstatement processes in human visceral pain. Neurobiol Learn Mem 116: 36 –45.
Benson S, Kattoor J, Kullmann JS, Hofmann S, Engler H, Forsting M et al (2014). Towards understanding sex differences in visceral pain: enhanced reactivation of classically-conditioned fear in healthy women. Neurobiol Learn Mem 109: 113–121.
LaBar KS, Phelps EA (2005). Reinstatement of conditioned fear in humans is context dependent and impaired in amnesia. Behav Neurosci 119: 677 –686.
综上所述，对特定事物过度的恐惧涉及几个环节：恐惧的巩固太牢、恐惧消退的功能太弱和恐惧恢复太活跃。
结合上面所说的基础知识，对于蜘蛛恐惧症的研究普遍认为蜘蛛恐惧症是由于杏仁核、岛叶、丘脑对于恐惧相关刺激过度的活化而导致的。尤其是在条件刺激（给怕蜘蛛的人看蜘蛛图片）时杏仁核暴走了啊！！！此外在条件刺激（看蜘蛛图）和非条件刺激（看蜘蛛本体）的时候脑区活动是由区别的，前者暴走的是杏仁核，而后者涉及工作记忆处理的dlPFC激活，是不是开始思考要怎么逃了！！
Curtis CE, D'Esposito M (2003). Persistent activity in the prefrontal cortex during working memory. Trends Cogn Sci 7: 415–423.
Schweckendiek J, Klucken T, Merz CJ, Tabbert K, Walter B, Ambach W et al (2011). Weaving the (neuronal) web: fear learning in spider phobia. Neuroimage 54: 681–688.
本文内容出自文献阅读汇报笔记部分内容。主题文献： Greco, J. A., & Liberzon, I. (2015). Neuroimaging of fear-associated learning. Neuropsychopharmacology Official Publication of the American College of Neuropsychopharmacology, 41(1).
