Ambulatorio di Neurologia, Polo Sanitario Barberini di Crevalcore, AUSL di Bologna, Italy.
Sleep Med. 2010 Apr;11(4):343-50. doi: 10.1016/j.sleep.2009.09.006. Epub 2010 Feb 4.
To describe the unique case of a middle-aged woman with severe insomnia recurring with a regular infradian period without any other significant clinical condition. To infer the existence of a circadian dysfunction modeled according to the physical phenomenon of the "beats."
PATIENT/METHODS: A two-year prospective observation by means of a sleep log was performed during the patient's normal life. She underwent one month of motor activity recording and also polysomnography, circadian rhythm of body core temperature and psychiatric evaluation during periods with and without insomnia.
Visual inspection of the 293-day plot of the sleep log disclosed a regular 42-day rhythm of insomnia recurrence confirmed by a Discrete Fourier Transform. During the periods of insomnia, lasting 5-7days, only moderate mood symptoms (depressive overlapping hypomaniac symptoms) were present. Treatment with sodium valproate was effective in curtailing insomnia.
The wax and wane infradian modulation of the sleep length suggested the presence of a basic mechanism similar to the physical phenomenon of the "beats," i.e., a long period modulation of the amplitude of an oscillating system due to the interference of two uncoupled oscillators with a slightly different oscillation frequency. Hypothesizing a dysfunction of the circadian component of sleep, namely two uncoupled circadian cycles, a simple mathematical model estimated the difference of their periods of oscillation |34+/-2min| and reproduced the sleep-log data of the drug-free period of observation.
描述一位中年女性严重失眠的独特案例，其失眠复发具有规律的亚日周期，且无其他明显临床症状。根据“拍”的物理现象推断存在昼夜节律功能障碍。
患者/方法：通过睡眠日志进行为期两年的前瞻性观察，记录患者正常生活期间的睡眠情况。在有和无失眠期间，她接受了一个月的运动活动记录和多导睡眠图、核心体温昼夜节律以及精神评估。
对睡眠日志的 293 天数据进行直观检查，揭示了失眠复发的规律 42 天周期，离散傅里叶变换对此进行了确认。在持续 5-7 天的失眠期间，仅存在中度情绪症状（抑郁重叠轻躁狂症状）。用丙戊酸钠治疗可有效缩短失眠期。
睡眠时长的亚日调制的起伏表明存在类似于“拍”的物理现象的基本机制，即由于两个略微不同的振荡频率的未耦合振荡器的干扰，振荡系统的幅度的长周期调制。假设睡眠的昼夜节律成分（即两个未耦合的昼夜节律周期）存在功能障碍，根据一个简单的数学模型，我们估计了它们的振荡周期的差异|34+/-2min|，并重现了观察期无药物治疗期间的睡眠日志数据。
