Cipolli Carlo, Pizza Fabio, Bellucci Claudia, Mazzetti Michela, Tuozzi Giovanni, Vandi Stefano, Plazzi Giuseppe
Department of Specialty, Diagnostic and Experimental Medicine, University of Bologna, Bologna, Italy.
Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy.
Front Neurosci. 2020 Nov 27;14:608757. doi: 10.3389/fnins.2020.608757. eCollection 2020.
The less rigid architecture of sleep in patients with narcolepsy type 1 (NT1) compared with healthy subjects may provide new insights into some unresolved issues of dream experience (DE), under the assumption that their DE frequencies are comparable. The multiple transition from wakefulness to REM sleep (sleep onset REM period: SOREMP) during the five trials of the Multiple Sleep Latency Test (MSLT) appears of particular interest. In MSLT studies, NT1 patients reported a DE after about 80% of SOREMP naps (as often as after nighttime REM sleep of themselves and healthy subjects), but only after about 30% of NREM naps compared to 60% of daytime and nighttime NREM sleep of healthy subjects. To estimate accurately the "real" DE frequency, we asked participants to report DE ("dream") after each MSLT nap and, in case of failure, to specify if they were unable to retrieve any content ("white dream") or DE did not occur ("no-dream"). The proportions of dreams, white dreams, and no dreams and the indicators of structural organization of DEs reported after NREM naps by 17 adult NT1 patients were compared with those reported by 25 subjects with subjective complaints of excessive daytime sleepiness (sc-EDS), who take multiple daytime NREM naps. Findings were consistent with the hypothesis of a failure in recall after awakening rather than in generation during sleep: white dreams were more frequent in NT1 patients than in sc-EDS subjects (42.86 vs 17.64%), while their frequency of dreams plus white dreams were similar (67.86 and 61.78%) and comparable with that of NREM-DEs in healthy subjects. The longer and more complex NREM-DEs of NT1 patients compared with sc-EDS subjects suggest that the difficulty in DE reporting depends on their negative attitude toward recall of contents less vivid and bizarre than those they usually retrieve after daytime SOREMP and nighttime REM sleep. As this attitude may be reversed by some recall training before MSLT, collecting wider amounts of DE reports after NREM naps would cast light on both the across-stage continuity in the functioning of cognitive processes underlying DE and the difference in content and structural organization of SOREM-DEs preceded by N1 or also N2 sleep.
假设发作性睡病1型（NT1）患者与健康受试者的梦境体验（DE）频率相当，那么与健康受试者相比，NT1患者睡眠结构缺乏刚性，这可能为一些尚未解决的梦境体验问题提供新的见解。多次睡眠潜伏期试验（MSLT）的五次试验中从清醒到快速眼动睡眠的多次转换（睡眠起始快速眼动期：SOREMP）似乎特别值得关注。在MSLT研究中，NT1患者在约80%的SOREMP小睡后报告有梦境体验（与他们自己及健康受试者夜间快速眼动睡眠后的频率相同），但与健康受试者白天和夜间非快速眼动睡眠的60%相比，只有约30%的非快速眼动小睡后报告有梦境体验。为了准确估计“真实”的梦境体验频率，我们要求参与者在每次MSLT小睡后报告梦境体验（“梦”），如果未能报告，则说明是无法回忆起任何内容（“白梦”）还是未发生梦境体验（“无梦”）。将17名成年NT1患者在非快速眼动小睡后报告的梦、白梦和无梦的比例以及梦境体验的结构组织指标，与25名有白天过度嗜睡主观主诉（sc-EDS）且白天有多次非快速眼动小睡的受试者报告的指标进行比较。研究结果与觉醒后回忆失败而非睡眠期间产生失败的假设一致：NT1患者的白梦比sc-EDS受试者更频繁（42.86%对17.64%），而他们的梦加白梦的频率相似（67.86%和61.78%），且与健康受试者非快速眼动梦境体验的频率相当。与sc-EDS受试者相比，NT1患者的非快速眼动梦境体验更长、更复杂，这表明梦境体验报告困难取决于他们对回忆不如白天SOREMP和夜间快速眼动睡眠后通常回忆起的内容生动和奇异的内容持消极态度。由于这种态度可能在MSLT前通过一些回忆训练得到扭转，收集更多非快速眼动小睡后的梦境体验报告会有助于阐明梦境体验背后认知过程功能的跨阶段连续性，以及N1或N2睡眠后SOREM-DEs在内容和结构组织上的差异。
