Cognitive-emotional hyperarousal as a premorbid characteristic of individuals vulnerable to insomnia.

OBJECTIVE: To examine whether cognitive-emotional hyperarousal is a premorbid characteristic of middle-aged and young good sleepers vulnerable to stress-related insomnia. METHODS: Self-reported information was collected from two samples of 305 middle-aged and 196 young adults. From those adults, 149 middle-aged (50.34 +/- 4.47 years) and 85 young (20.19 +/- 1.31 years) good sleepers were selected for the present study. The Ford Insomnia Response to Stress Test (FIRST) was used to measure vulnerability to stress-related insomnia. Trait measures of personality, arousability, rumination, presleep arousal, and coping skills were entered as predictors in the linear regression models, at the same time controlling for gender, depression, and anxiety. RESULTS: The regression models showed that arousability (beta = 0.546), neuroticism (beta = 0.413), perceived stress (beta = 0.375), and rumination (beta = 0.214) were associated with FIRST scores in middle-aged adults. Among young adults, the regression models revealed that presleep cognitive arousal (beta = 0.448), arousability (beta = 0.426), neuroticism (beta = 0.320), presleep somatic arousal (beta = 0.290), emotion-oriented coping (beta = 0.220), and rumination (beta = 0.212) were associated with FIRST scores. Finally, individuals with high FIRST scores did not show lower scores in measures of cognitive-emotional hyperarousal compared with chronic insomniacs. CONCLUSIONS: These data suggest that cognitive-emotional hyperarousal may be a premorbid characteristic of subjects vulnerable to insomnia. It seems that maladaptive coping stress strategies and cognitive-emotional hyperarousal predispose to the development of insomnia and that interventions targeting these characteristics may be important in the prevention and treatment of chronic insomnia.

Evidence of subthalamic PGO-like waves during REM sleep in humans: a deep brain polysomnographic study.

STUDY OBJECTIVES: The aim of this study was to examine whether the subthalamic nucleus (STN) plays a role in the transmission of PGO-like waves during REM sleep in humans. DESIGN: Simultaneous recordings from deep brain electrodes to record local field potentials (LFPs), and standard polysomnography to ascertain sleep/wake states. SETTING: Main Hospital, department of clinical neurophysiology sleep laboratory. PARTICIPANTS: 12 individuals with Parkinson's disease, with electrodes implanted in the STN; and, as a control for localization purposes, 4 cluster headache patients with electrodes implanted in the posterior hypothalamus. INTERVENTIONS: All subjects underwent functional neurosurgery for implantation of deep brain stimulation electrodes. RESULTS: Sharp, polarity-reversed LFPs were recorded within the STN during REM sleep in humans. These subthalamic PGO-like waves (2-3 Hz, 80-200 pV, and 300-500 msec) appeared during REM epochs as singlets or in clusters of 3-13 waves. During the pre-REM period, subthalamic PGO-like waves were temporally related to drops in the submental electromyogram and/or onset of muscular atonia. Clusters of PGO-like waves occurred typically before and during the bursts of rapid eye movements and were associated with an enhancement in fast (15-35 Hz) subthalamic oscillatory activity. CONCLUSION: Subthalamic PGO-like waves can be recorded during pre-REM and REM sleep in humans. Our data suggest that the STN may play an active role in an ascending activating network implicated in the transmission of PGO waves during REM sleep in humans.

Nighttime sleep and daytime functioning correlates of the insomnia complaint in young adults.

The nighttime and daytime correlates of the insomnia complaint (IC) were assessed in an in-class survey on a sample of 1238 first year university students (18.85+/-1.45 years) at the Universidad Autónoma of Madrid, Spain. Evidence was found that the likelihood of complaining of insomnia was increased by perceiving difficulties with initiating and maintaining sleep, reporting low quality of nocturnal sleep, having a long sleep onset latency and having an evening circadian preference. The most strongly related daytime variables to IC being perceived difficulties in concentrating, feelings of irritability and fatigue, and symptoms of anxiety and depression. The data, in addition to confirm those of clinical studies on subjects complaining of insomnia, suggest that having an evening chronotype increases the vulnerability of adolescents and young adults to complain of insomnia.