Department of Psychiatry and Psychotherapy, Freiburg University Medical Center, Freiburg, Germany.
Pharmacopsychiatry. 2012 Jul;45(5):167-76. doi: 10.1055/s-0031-1299721. Epub 2012 Jan 30.
Chronic insomnia afflicts approximately 10% of the adult population and is associated with daytime impairments and an elevated risk for developing somatic and mental disorders. Current pathophysiological models propose a persistent hyperarousal on the cognitive, emotional and physiological levels. However, the marked discrepancy between minor objective alterations in standard parameters of sleep continuity and the profound subjective impairment in patients with insomnia is unresolved. We propose that "instability" of REM sleep contributes to the experience of disrupted and non-restorative sleep and to the explanation of this discrepancy. This concept is based on evidence showing increased micro- and macro-arousals during REM sleep in insomnia patients. As REM sleep represents the most highly aroused brain state during sleep it seems particularly prone to fragmentation in individuals with persistent hyperarousal. The continuity hypothesis of dream production suggests that pre-sleep concerns of patients with insomnia, i. e., worries about poor sleep and its consequences, dominate their dream content. Enhanced arousal during REM sleep may render these wake-like cognitions more accessible to conscious perception, memory storage and morning recall, resulting in the experience of disrupted and non-restorative sleep. Furthermore, chronic fragmentation of REM sleep might lead to dysfunction in a ventral emotional neural network, including limbic and paralimbic areas that are specifically activated during REM sleep. This dysfunction, along with attenuated functioning in a dorsal executive neural network, including frontal and prefrontal areas, might contribute to emotional and cognitive alterations and an elevated risk of developing depression.
慢性失眠影响约 10%的成年人群，与日间损伤和躯体及精神障碍风险增加有关。目前的病理生理模型提出认知、情感和生理水平持续的过度觉醒。然而，在失眠患者中，标准睡眠连续性参数的微小客观改变与深刻的主观损伤之间存在明显的差异，这一差异仍未得到解决。我们提出，快速眼动（REM）睡眠的“不稳定性”导致了睡眠中断和非恢复性睡眠的体验，并解释了这一差异。这一概念基于以下证据：失眠患者在 REM 睡眠期间微觉醒和大觉醒增加。由于 REM 睡眠是睡眠期间大脑最活跃的状态，因此在持续过度觉醒的个体中，它似乎特别容易碎片化。梦产生的连续性假说表明，失眠患者的睡前担忧，即对睡眠质量差及其后果的担忧，主导了他们的梦境内容。REM 睡眠期间增强的觉醒可能使这些类似于清醒的认知更容易被意识感知、记忆存储和早晨回忆，从而导致睡眠中断和非恢复性睡眠。此外，REM 睡眠的慢性碎片化可能导致包括边缘和旁边缘区域在内的腹侧情绪神经网络功能障碍，这些区域在 REM 睡眠期间特异性激活。这种功能障碍，以及包括额极和前额区在内的背侧执行神经网络功能减弱，可能导致情绪和认知改变，并增加患抑郁症的风险。
