Department of Psychology, University of Cape Town, Cape Town, South Africa.
Department of Experimental Psychology, Utrecht University, Utrecht, the Netherlands; Department of Psychiatry and Mental Health, University of Cape Town, Groote Schuur Hospital, Cape Town, South Africa.
Cortex. 2019 Apr;113:169-183. doi: 10.1016/j.cortex.2018.12.016. Epub 2018 Dec 25.
Neuroimaging studies have repeatedly shown amygdala activity during sleep (REM and NREM). Consequently, various theorists propose central roles for the amygdala in dreaming - particularly in the generation of dream affects, which seem to play a major role in dream plots. However, a causal role for the amygdala in dream phenomena has never been demonstrated. The traditional first step in determining this role is to observe the functional effects of isolated lesions to the brain structure in question. However, circumscribed bilateral amygdala lesions are extremely rare. Furthermore, the treatment of the amygdala as a unitary structure is problematic, as the basolateral and centromedial amygdala (BLA and CMA) may serve very different functions. We analysed 23 dream reports collected from eight adult patients with bilateral calcification of the BLA as a result of a very rare genetic condition called Urbach-Wiethe Disease (UWD). We compared these dream reports to 52 reports collected from 17 matched controls. Given that the BLA has been implicated in various affective processes in waking life, we predicted that the emotional content of the patients' dreams would differ from that of controls. Due to the exploratory nature of this research, a range of different dream characteristics were analysed. A principal components analysis run on all data returned three key factors, namely pleasantness, length and danger. The UWD patients' dream reports were significantly more pleasant and significantly shorter and less complex than control reports. No differences were found in levels of threat or danger. The results support some current hypotheses concerning the amygdala's role in dreaming, and call others into question. Future research should examine whether these UWD patients show generally impaired emotional episodic memory due to BLA damage, which could explain some of the current findings.
神经影像学研究反复表明，杏仁核在睡眠（REM 和 NREM）期间活动。因此，各种理论家提出杏仁核在做梦中的核心作用 - 特别是在产生梦的影响方面，这些影响似乎在梦情节中起着主要作用。然而，杏仁核在梦现象中的因果作用从未得到证明。确定这一作用的传统第一步是观察孤立的脑结构损伤对大脑结构的功能影响。然而，局限性双侧杏仁核损伤极为罕见。此外，将杏仁核视为单一结构存在问题，因为基底外侧和中央杏仁核（BLA 和 CMA）可能具有非常不同的功能。我们分析了从八位患有双侧 BLA 钙化的成年患者中收集的 23 份梦境报告，这是一种非常罕见的遗传疾病，称为乌尔巴赫 - 威蒂病（UWD）。我们将这些梦境报告与从 17 名匹配的对照组中收集的 52 份报告进行了比较。鉴于杏仁核在清醒状态下的各种情感过程中都有牵连，我们预测患者的梦境的情绪内容会与对照组有所不同。由于这项研究具有探索性，因此分析了一系列不同的梦境特征。对所有数据进行的主成分分析返回了三个关键因素，即愉悦度、长度和危险。UWD 患者的梦境报告比对照组的报告明显更愉悦、明显更短、更简单。在威胁或危险水平上没有发现差异。结果支持了一些关于杏仁核在做梦中的作用的当前假设，并对其他假设提出了质疑。未来的研究应该检查这些 UWD 患者是否由于 BLA 损伤而表现出一般的情感情景记忆受损，这可以解释一些当前的发现。
