Department of Psychology, Université de Montréal, Montréal, Québec, Canada.
Center for Advanced Research in Sleep Medicine, CIUSSS-NÎM - Hôpital du Sacré-Coeur de Montréal, Montréal, Québec, Canada.
J Clin Sleep Med. 2019 Feb 15;15(2):253-264. doi: 10.5664/jcsm.7628.
Growing evidence suggests that nightmares have considerable adverse effects on waking behavior, possibly by increasing post-sleep negative emotions. Dysphoric reactions to nightmares are one component of nightmare severity for which the neural correlates are unknown. Here, we investigate possible neural correlates of nightmare severity in a sample of individuals who frequently recall nightmares.
Our principal measure of nightmare severity is nightmare distress as indexed by the Nightmare Distress Questionnaire (NDQ), and secondary measures are retrospective and prospective estimates of frequency of recalling dysphoric dreams (DD). We used high-resolution technetium 99m ethyl cysteinate dimer single photon emission computed tomography to assess regional cerebral blood flow (rCBF) while 18 individuals who were frequent nightmare recallers viewed negative and neutral pictures from the International Affective Picture System. We correlated rCBF with NDQ scores and DD recall frequency estimates.
Negative correlations were observed between NDQ scores and rCBF during negative picture viewing in bilateral insula and anterior cingulate, right medial frontal gyrus, bilateral superior temporal gyrus, right inferior frontal and precentral gyri, and bilateral putamen. Retrospective DD recall correlated with rCBF activity primarily in regions overlapping those related to NDQ scores. Prospective DD recall was only weakly related to rCBF. Results for the neutral condition overlapped partially with those for the negative condition; in particular, NDQ and retrospective DD recall were related to rCBF in medial prefrontal and anterior cingulate gyri.
Results point to a possible overlap in brain mechanisms involved in nightmare dysphoria (during sleep) and distress (during wakefulness) among individuals who frequently recall nightmares. They provide partial support for a neurocognitive model of nightmares.
A commentary on this article appears in this issue on page 179.
越来越多的证据表明，噩梦对清醒行为有很大的负面影响，可能是通过增加睡眠后的负面情绪。对噩梦的抑郁反应是噩梦严重程度的一个组成部分，其神经相关性尚不清楚。在这里，我们研究了一组经常回忆噩梦的个体中噩梦严重程度的可能神经相关性。
我们衡量噩梦严重程度的主要指标是噩梦困扰程度，用噩梦困扰问卷（NDQ）来衡量，次要指标是回忆不愉快梦（DD）的频率的回顾性和前瞻性估计。我们使用高分辨率锝 99m 乙基半胱氨酸二聚体单光子发射计算机断层扫描来评估 18 名经常回忆噩梦的个体在观看国际情感图片系统的负面和中性图片时的局部脑血流（rCBF）。我们将 rCBF 与 NDQ 评分和 DD 回忆频率估计值相关联。
在观看负面图片时，NDQ 评分与双侧岛叶和前扣带回、右侧额内侧回、双侧颞上回、右侧额下回和中央前回以及双侧壳核的 rCBF 呈负相关。回顾性 DD 回忆与 rCBF 活动主要在与 NDQ 评分相关的区域重叠。前瞻性 DD 回忆与 rCBF 的相关性较弱。中性条件的结果与负面条件部分重叠；特别是，NDQ 和回顾性 DD 回忆与内侧前额叶和前扣带回回的 rCBF 相关。
结果表明，在经常回忆噩梦的个体中，睡眠时的噩梦抑郁（在睡眠中）和觉醒时的痛苦（在觉醒时）可能涉及到相同的大脑机制。它们为噩梦的神经认知模型提供了部分支持。
本文的一篇评论见本期第 179 页。
