Nielsen Tore
Dream and Nightmare Laboratory, Center for Advanced Research in Sleep Medicine, CIUSSS-NÎM - Hôpital du Sacré-Coeur de Montréal, Montreal, QC, Canada.
Department of Psychiatry, Université de Montreal, Montreal, QC, Canada.
Front Neurol. 2017 Jun 1;8:201. doi: 10.3389/fneur.2017.00201. eCollection 2017.
Adverse childhood experiences can deleteriously affect future physical and mental health, increasing risk for many illnesses, including psychiatric problems, sleep disorders, and, according to the present hypothesis, idiopathic nightmares. Much like post-traumatic nightmares, which are triggered by trauma and lead to recurrent emotional dreaming about the trauma, idiopathic nightmares are hypothesized to originate in early adverse experiences that lead in later life to the expression of early memories and emotions in dream content. Accordingly, the objectives of this paper are to (1) review existing literature on sleep, dreaming and nightmares in relation to early adverse experiences, drawing upon both empirical studies of dreaming and nightmares and books and chapters by recognized nightmare experts and (2) propose a new approach to explaining nightmares that is based upon the Stress Acceleration Hypothesis of mental illness. The latter stipulates that susceptibility to mental illness is increased by adversity occurring during a developmentally sensitive window for emotional maturation-the that ends around age 3½. Early adversity accelerates the neural and behavioral maturation of emotional systems governing the expression, learning, and extinction of fear memories and may afford short-term adaptive value. But it also engenders long-term dysfunctional consequences including an increased risk for nightmares. Two mechanisms are proposed: (1) disruption of infantile amnesia allows normally forgotten early childhood memories to influence later emotions, cognitions and behavior, including the common expression of threats in nightmares; (2) alterations of normal emotion regulation processes of both waking and sleep lead to increased fear sensitivity and less effective fear extinction. These changes influence an affect network previously hypothesized to regulate fear extinction during REM sleep, disruption of which leads to nightmares. This network consists of a fear circuit that includes amygdala, hippocampus, and medial prefrontal cortex and whose substantial overlap with the stress acceleration findings allows the latter to be incorporated into a wider, more developmentally coherent framework.
童年不良经历会对未来的身心健康产生有害影响，增加患多种疾病的风险，包括精神问题、睡眠障碍，以及根据目前的假设，特发性噩梦。与创伤后噩梦非常相似，创伤后噩梦由创伤引发，导致反复出现关于创伤的情感梦境，特发性噩梦据推测起源于早期不良经历，这些经历在以后的生活中导致早期记忆和情感在梦境内容中表达。因此，本文的目的是：（1）回顾关于睡眠、做梦和噩梦与早期不良经历相关的现有文献，借鉴关于做梦和噩梦的实证研究以及知名噩梦专家的书籍和章节；（2）提出一种基于精神疾病应激加速假说的解释噩梦的新方法。后者规定，在情感成熟的发育敏感期（大约在3岁半结束）发生的逆境会增加患精神疾病的易感性。早期逆境加速了控制恐惧记忆表达、学习和消退的情感系统的神经和行为成熟，可能具有短期适应性价值。但它也会产生长期的功能失调后果，包括噩梦风险增加。提出了两种机制：（1）婴儿期遗忘的破坏使通常被遗忘的童年早期记忆影响后来的情绪、认知和行为，包括噩梦中威胁的常见表达；（2）清醒和睡眠中正常情绪调节过程的改变导致恐惧敏感性增加和恐惧消退效果降低。这些变化影响了一个先前假设在快速眼动睡眠期间调节恐惧消退的情感网络，该网络的破坏会导致噩梦。这个网络由一个恐惧回路组成，包括杏仁核、海马体和内侧前额叶皮质，其与应激加速研究结果的大量重叠使得后者能够被纳入一个更广泛、更具发育连贯性的框架。
