Nightmares do result in psychophysiological arousal: A multimeasure ambulatory assessment study.

Individuals who frequently experience nightmares report compromised sleep quality, poor daytime mood, and functioning. Previous research has aimed at linking these impairments with altered sleep architecture, but results were inconclusive. One plausible explanation is that only a few studies recorded markers of autonomic nervous system activity. For the first time, this study collected such markers under ecologically valid conditions with ambulatory assessment. In 19 individuals with frequent nightmares (≥1 nightmare/week) and 19 healthy control participants (<1 nightmare/month), measures indicating autonomic activation (heart rate, heart rate variability, respiration cycle length, electrodermal fluctuations, EEG arousals, saliva cortisol, REM density) were collected while applying ambulatory polysomnographic assessment during 3 consecutive nights. When nightmare participants reported a nightmare, we analyzed the last 5 min of REM sleep before awakening and compared these data to their non-nightmares as well as to the dream episodes of control participants. Overall, there were no general differences in autonomic activation of nightmare sufferers compared to control participants. However, when nightmare participants experienced nightmares, autonomic activation was markedly increased compared to their own non-nightmares and, to some extent, to control participant's dreams. Significant intraindividual differences were found for all autonomic measures except in participant's EEG arousals and cortisol levels. Group differences were found in EEG arousals and heart rate. In conclusion, ambulatory polysomnography demonstrates that nightmares are accompanied by increased autonomic activation. Results support the notion of impaired self-reported sleep quality caused by one's autonomic response rather than altered sleep pattern.

Nightmares affect the experience of sleep quality but not sleep architecture: an ambulatory polysomnographic study.

BACKGROUND: Nightmares and bad dreams are common in people with emotional disturbances. For example, nightmares are a core symptom in posttraumatic stress disorder and about 50% of borderline personality disorder patients suffer from frequent nightmares. Independent of mental disorders, nightmares are often associated with sleep problems such as prolonged sleep latencies, poorer sleep quality, and daytime sleepiness. It has not been well documented whether this is reflected in objectively quantifiable physiological indices of sleep quality. METHODS: Questionnaires regarding subjective sleep quality and ambulatory polysomnographic recordings of objective sleep parameters were collected during three consecutive nights in 17 individuals with frequent nightmares (NM) and 17 healthy control participants (HC). RESULTS: NM participants reported worse sleep quality, more waking problems and more severe insomnia compared to HC group. However, sleep measures obtained by ambulatory polysomnographic recordings revealed no group differences in (a) overall sleep architecture, (b) sleep cycle duration as well as REM density and REM duration in each cycle and (c) sleep architecture when only nights with nightmares were analyzed. CONCLUSIONS: Our findings support the observation that nightmares result in significant impairment which is independent from disturbed sleep architecture. Thus, these specific problems require specific attention and appropriate treatment.

Pineal gland volume in primary insomnia and healthy controls: a magnetic resonance imaging study.

Little is known about the relation between pineal volume and insomnia. Melatonin promotes sleep processes and, administered as a drug, it is suitable to improve primary and secondary sleep disorders in humans. Recent magnetic resonance imaging studies suggest that human plasma and saliva melatonin levels are partially determined by the pineal gland volume. This study compares the pineal volume in a group of patients with primary insomnia to a group of healthy people without sleep disturbance. Pineal gland volume (PGV) was measured on the basis of high-resolution 3 Tesla MRI (T1-magnetization prepared rapid gradient echo) in 23 patients and 27 controls, matched for age, gender and educational status. Volume measurements were performed conventionally by manual delineation of the pineal borders in multi-planar reconstructed images. Pineal gland volume was significantly smaller (P < 0.001) in patients (48.9 ± 26.6 mm(3) ) than in controls (79 ± 30.2 mm(3) ). In patients PGV correlated negatively with age (r = -0.532; P = 0.026). Adjusting for the effect of age, PGV and rapid eye movement (REM) latency showed a significant positive correlation (rS  = 0.711, P < 0.001) in patients. Pineal volume appears to be reduced in patients with primary insomnia compared to healthy controls. Further studies are needed to clarify whether low pineal volume is the basis or the consequence of functional sleep changes to elucidate the molecular pathology for the pineal volume loss in primary insomnia.

Sleep and dreaming in patients with borderline personality disorder: a polysomnographic study.

Previous research has demonstrated disturbances in sleep continuity in subjects with borderline personality disorders (BPD). Moreover, depression-like sleep abnormalities like reduced REM latency have been found in BPD subjects, even without comorbid major depression disorder. Yet it is still unknown what the effect is of co-morbid posttraumatic stress disorder on sleep continuity and dream content in BPD patients group. The present study compared 27 unmedicated female BPD subjects and healthy controls. The patients exhibited increased sleep fragmentation, increased REM density, and reduced REM latency. The findings were independent from co-morbid posttraumatic stress response (PTSD), which was present in 33% of the patient sample. Negatively toned dreams obtained by REM awakenings and nightmares were also reported more often by the patients-also irrespective of co-morbid PTSD-whereas dreams of specific BPD behavior, like self-mutilation, were rare. Taking these finding into account, one might productively investigate whether the sleep abnormalities improve during successful treatment of BPD and whether efficient methods for treating nightmares can be beneficial for this patient group.