Sleep microstructure around sleep onset differentiates major depressive insomnia from primary insomnia

Abstract

Summary In the present study we investigate whether alterations of sleep propensity or of wake propensity are implicated in sleep initiation disturbances encountered in major depressive insomnia and in primary insomnia. For this purpose, the time course of electroencephalogram (EEG) power density during the period preceding sleep onset and during the first non‐rapid eye movement (REM) period was examined in three age and gender matched groups of 10 women and 11 men (healthy controls, primary insomniacs and depressive insomniacs). In contrast to healthy controls and depressive insomniacs, patients with primary insomnia did not experience a gradual decrease of their alpha and beta1 power during the sleep onset period and had a lower delta activity in the 5 min preceding sleep onset. Compared with the two other groups, depressive patients exhibit less dynamic changes in slow wave activity during the first non‐REM period. The present results suggest that hyperarousal (high ‘Process W’) may mainly be implicated in the sleep initiation difficulties of primary insomniacs whereas the homeostatic sleep regulation process seems to be partially maintained. In our major depressed patients, the sleep initiation disturbances appeared to relate to a lower sleep pressure (low ‘Process S’) rather than to hyperarousal. This study supports the idea that different mechanisms are implicated in sleep disturbances experienced by primary insomniacs and major depressive insomniacs.

Next-day residual effects of hypnotics in DSM-IV primary insomnia: a driving simulator study with simultaneous electroencephalogram monitoring

“…This issue is of particular importance since many reports show electrophysiological and psychomotor evidences of increased daytime hyperarousal in insomniac patients (Schneider-Helmert 1987;Regenstein et al 1993;Stepanski et al 1988;Staner et al 2003). At first sight, one may hypothesise that daytime hyperarousal could have a protective effect against residual hypnotic-induced sedation.…”

REM and NREM power spectral analysis on two consecutive nights in psychophysiological and paradoxical insomnia sufferers

“…Sleep microstructure, mainly assessed through the activity of different frequency bands at central sites with power spectral analysis (PSA), presents also particularities in PI compared to GS. At sleep onset, less delta power and more beta and alpha spectral powers are observed (Merica and Gaillard, 1992;Lamarche and Ogilvie, 1997;Staner et al, 2003). Altogether, results in non rapid eye movement (NREM) sleep suggest higher beta1, beta2 and gamma spectral power (Merica et al, 1998;Perlis et al, 2001a).…”

Ambulatory sleep-wake patterns and variability in young people with emerging mental disorders

“…In the context of both anxiety and affect ive J Psychiatry Neurosci 2015;40(1) disorders, difficulties in sleep initiation and maintenance have been postulated to result from hyperarousal and/or impaired sleep drive. [49][50][51][52] This is likely to feed a vicious cycle between sleep disturbances and mood alterations. For instance, elevated cortisol around sleep onset has been associated with depression recurrence in adolescents.…”