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At least 19 recordsLinked to original sources

PubMed2026

Effects of a programmed reflexology therapy on sleep quality, insomnia, and fatigue among individuals with poor sleep quality: evidence for autonomic nervous system modulation.

Poor sleep quality is closely associated with autonomic dysregulation and increased risks of cardiovascular, metabolic, and mental disorders. Foot reflexology is a widely used complementary therapy; however, its physiological mechanisms and comparative efficacy remain insufficiently explored. This study aimed to compare the effects of manual reflexology treatment (MRT) and foot massage equipment (FEM) on autonomic nervous system function, sleep quality, insomnia severity, and fatigue in adults with poor sleep quality. Using a randomized crossover design, 32 participants with poor sleep quality received MRT and FEM interventions for 6 weeks each (once weekly, 30-40 min/session). Heart rate (HR), blood pressure, and heart rate variability (HRV; time- and frequency-domain indices) were assessed at weeks 1 and 6 before and after each intervention. Subjective outcomes included the Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), and Fatigue Assessment Scale (FAS). Following MRT, participants demonstrated significantly greater reductions in global PSQI scores and all PSQI components compared with FEM. MRT also resulted in larger improvements in insomnia severity and both mental and physical fatigue. In contrast, FEM primarily improved physical fatigue. Physiologically, MRT induced an immediate decrease in HR and significant increases in HRV time-domain indices (SDNN, RMSSD, pNN50), which were sustained after 6 weeks. Frequency-domain analysis further revealed reduced LF, increased HF, and a lower LF/HF ratio, indicating enhanced parasympathetic activity and cumulative autonomic modulation. In conclusion, programmed manual reflexology, delivered according to the TIDieR framework, is more effective than mechanical foot massage in improving autonomic balance, sleep quality, insomnia severity, and fatigue in individuals with poor sleep quality. These findings support MRT as a feasible and evidence-based non-pharmacological complementary intervention for sleep health promotion. TRIAL REGISTRATION: clinicaltrials.gov; NCT Number: NCT07402460; Registered 3 February 2026.

Adult↗

PubMed2025

Gut metagenome and plasma metabolome profiles in older adults suggest pyruvate metabolism as a link between sleep quality and frailty.

Poor sleep quality is associated with increased frailty in older adults, but the role of the gut microbiome in this relationship remains unclear. Here, gut metagenome and plasma metabolome were profiled in 1,225 individuals aged 62-96 years. Poor sleep quality was associated with reduced abundances of potential probiotics such as Faecalibacterium prausnitzii and elevated abundances of pathobionts. A gut microbiome sleep quality index (GMSI) was developed to quantify microbial balance related to better sleep quality; higher GMSI scores were inversely associated with frailty and related clinical traits. Pyruvate metabolism emerged as a key microbial pathway linking sleep quality to frailty, with features such as F. prausnitzii abundance and microbial pyridoxal 5'-phosphate biosynthesis implicated in this connection. These findings deepen our understanding of microbiome-metabolome pathways related to sleep quality and frailty in aging and provide a valuable resource for future longitudinal and interventional studies.

Humans↗

PubMed2026

Transcutaneous vagus nerve stimulation influences sleep quality and insomnia: A systematic review and meta-analysis.

Impairments in sleep quality, timing, or duration disrupt normal sleep patterns. This systematic review and meta-analysis investigated the effects of transcutaneous vagus nerve stimulation (tVNS) protocols on sleep outcomes. Thirteen randomized controlled trials with parallel or crossover designs that applied tVNS intervention and assessed sleep quality (Pittsburgh Sleep Quality Index) and insomnia severity (Athens Insomnia Scale and Insomnia Severity Index) were included. Effect sizes were calculated by comparing changes between the active tVNS and control groups. Moderator analyses examined whether stimulation of different targeted regions influences sleep outcomes. Meta-regression analyses examined potential relationships between the effects of tVNS protocols on sleep quality and demographic characteristics and multiple tVNS parameters, respectively. The random-effects meta-analysis indicated that tVNS protocols influenced better sleep quality and lower insomnia severity. Moderator variable analysis revealed that tVNS targeting the concha region induced better sleep quality. Meta-regression analysis revealed that better sleep quality was associated with lower ages of participants. These findings suggest that tVNS protocols, particularly those targeting the concha, were associated with favorable changes in sleep quality and insomnia severity, with age potentially moderating the treatment response.

Humans↗

PubMedDate not supplied

[Studies on sleep quality in old age].

A survey of 480 randomly chosen men and women over 65 years of age observed complaints concerning the quality of sleep in 26%, the use of sleeping drugs in 33%; complaints and/or drugs were found in 45% of cases. On the average complaints were more often made by women. The percentage of men complaining increased from 65 to 90+ years. In the group over 90 years of age both sexes showed the same frequency. The quality of sleep was correlated with self-rated health-status, mobility and impairment especially of the cardiovascular system. No correlations were found with contentment, place of residence, noise, outdoor exercise and socioeconome status. Sleeping drugs were most effective in subjects with cerebral impairment and of least effect when subjects suffered from cardiovascular trouble.

Age Factors↗

PubMed2026

Sex modifies the association of high-altitude hypoxia with poor sleep quality and depression in school-age children and adolescents.

BACKGROUND: While chronic exposure to high-altitude hypoxia is known to impair sleep and mental health, whether these effects are sex-dependent remains unclear. This study addresses a critical gap by investigating how sex modifies the association between high-altitude hypoxia and risks of poor sleep quality, depressive symptoms, and their co-occurrence in children and adolescents. METHODS: In this cross-sectional study (March-May 2024), we enrolled 1,345 long-term residents of the Shannan Tibet Autonomous Prefecture (altitude: 3,650-4,800 m) and 2,909 age-matched controls from low-altitude plains (Anhui Province, China). Sleep quality and depression were assessed using the Pittsburgh Sleep Quality Index (PSQI) and Montgomery-Asberg Depression Rating Scale (MADRS), respectively. Sex-stratified analyses and interaction metrics (RERI/AP/SI) were employed to evaluate additive and multiplicative effects. RESULTS: High-altitude residents exhibited significantly higher prevalence of poor sleep (24.2% vs. 18.7%, P < 0.001), depression (23.6% vs. 15.3%, P < 0.001), and their co-occurrence (12.6% vs. 8.6%, P < 0.001) compared to low-altitude controls. A significant negative additive interaction (RERI = - 0.78, 95% CI: -1.35 to - 0.3; P < 0.001) indicated that sex modifies the altitude-outcome association. Specifically: (1) high-altitude residence significantly increased poor sleep risk in males (OR = 1.60, 95% CI: 1.26-2.03) but not in females (OR = 1.39, 95% CI: 1.07-1.79); and (2) the expected female predominance in poor sleep observed in the plain region (OR = 1.452, 95% CI: 1.191-1.769) disappeared in the plateau region (OR = 0.865, 95% CI: 0.667-1.121). Similar patterns were independently replicated for depressive symptoms. These findings confirm that high-altitude exposure differentially increases risk in males rather than protecting females. CONCLUSION: Males show marked vulnerability to high-altitude-associated sleep and mood impairments, while females demonstrate resilience. Sex-tailored interventions for high-altitude populations, particularly targeting male adolescents, are urgently needed.

Humans↗

PubMed2026

Efficacy of transcranial alternating current stimulation for musculoskeletal pain and sleep quality: a systematic review and meta-analysis.

BACKGROUND: Transcranial alternating current stimulation (tACS) is a non-invasive neuromodulation technique, emerging as a potential therapeutic option for musculoskeletal pain management. OBJECTIVE: To comprehensively evaluate the efficacy and safety of tACS for alleviating pain and improving sleep quality in adults with musculoskeletal pain. METHODS: We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs). Seven major databases and other sources were searched from inception until April 2026. Two reviewers independently screened studies, extracted data, and assessed risk of bias. A random-effects model was used to pool standardized mean differences (SMDs). The certainty of evidence was evaluated using the Grading of Recommendation Assessment, Development, and Evaluation framework. RESULTS: Six RCTs involving 232 participants were included. Meta-analysis showed that tACS could significantly reduce pain intensity compared to control (SMD = -0.355, 95% CI: -0.625 to -0.084, p = 0.010, I² = 28.7%). However, no significant improvement was found for sleep quality (SMD = 0.004, 95% CI: -0.310-0.317, p = 0.982, I² = 0.0%). Adverse effects were mild and transient, comparable to sham stimulation. The overall certainty of evidence was rated as low for both pain and sleep quality outcomes. CONCLUSION: Current evidence suggests that tACS may be beneficial for musculoskeletal pain; however, the available evidence remains limited and should be interpreted cautiously. The effect of tACS on sleep quality remains uncertain because of the limited number of available studies. Future well-designed RCTs with standardized outcome measures, condition-specific stimulation protocols, and longer follow-up are required to establish the efficacy and long-term safety of tACS.

Humans↗

PubMed2026

Effectiveness of Auricular Acupressure in Improving Sleep Quality and Reducing Insomnia Severity in Middle-Aged and Older Women in Taiwan.

Poor sleep quality impacts cognition, emotions, and immunity. This study evaluated the efficacy of auricular acupressure in improving sleep conditions. Eighty-eight women aged ≥40 years with insomnia were randomly assigned to acupoint, sham, or comparison groups. Magnetic pellets were applied to heart, liver, and shenmen acupoints for the acupoint group and were offset by 1 to 2 cm for the sham group. Participants pressed pellets thrice daily for 1 month. In the acupoint and sham groups, insomnia was reduced and sleep quality improved dramatically in the acupoint group at 4 weeks. Auricular acupressure may improve sleep and support equitable, cultural patient-centered care.

Adult↗

PubMed2026

Blue light therapy delivered through light glasses improves sleep quality and daytime sleepiness in Parkinson's disease: A randomized trial.

BackgroundSleep disturbances, including excessive daytime sleepiness (EDS) and fragmented nocturnal sleep, are common in Parkinson's disease (PD) and significantly reduce quality of life. This pilot study evaluated the efficacy of a novel approach using blue light, delivered via dedicated glasses with integrated LED lights, to improve sleep and non-motor symptoms.MethodsRandomised, placebo-controlled, single-blind pilot study with a 2-week light intervention. Participants were assessed at baseline, two weeks, and five weeks. The study was designed to evaluate between- and within-group changes. Participants were randomly allocated to receive blue light therapy (n = 15) or red light placebo (n = 15), delivered via LED-integrated glasses for one hour, twice daily, given for a 2-week period. Primary outcome was improvement in sleep quality, assessed via the Pittsburgh Sleep Quality Index. Secondary outcomes included diary-based sleep outcomes, excessive daytime sleepiness, mood, anxiety, and motor symptoms.ResultsThere was a significant group × time effect with blue light therapy leading to better Pittsburgh Sleep Quality Index scores (p = 0.021). Between-group analyses showed that at two weeks a trend toward significance was observed (p = 0.065), while sleep quality significantly improved at five weeks compared to placebo (p = 0.029) with a large effect size (0.896). Excessive sleepiness improved in the blue light group (p < 0.001), with a reduction in clinically relevant sleepiness from 50.0% to 6.7% (p = 0.005).ConclusionsBlue light therapy delivered through dedicated glasses appeared to show an improvement in sleep quality and daytime sleepiness in individuals with PD. Blue light therapy offers a promising alternative to traditional light therapy utilising lower light intensities and eliminating the need for light boxes.

Aged↗

PubMed2026

Efficacy of Mindfulness-Based Interventions on Anxiety and Sleep Quality in Patients with Breast Cancer: A Systematic Review and Meta-Analysis.

INTRODUCTION: Patients with breast cancer commonly experience anxiety and sleep disturbance during and after treatment, and these symptoms are closely interrelated, negatively affecting the quality of life. Mindfulness-based interventions (MBIs) have been increasingly used as a nonpharmacological supportive approach. This systematic review and meta-analysis aimed to evaluate the effects of MBIs on anxiety and sleep quality in patients with breast cancer. METHODS: A systematic search of PubMed, Web of Science, Cochrane Library, CINAHL, and Embase was conducted up to May 15, 2025. Random-effects meta-analysis was used to estimate standardized mean differences (SMDs) with 95% confidence intervals (CIs). Risk of bias was assessed using the Cochrane RoB 2.0, and the certainty of evidence was evaluated with Grading of Recommendations, Assessment, Development, and Evaluation. RESULTS: Twenty-four randomized controlled trials (RCTs) including 3,212 participants were analyzed. MBIs significantly reduced anxiety compared with control groups receiving usual care, no intervention, or wait-list conditions (SMD: -0.47, 95% CI: -0.62 to -0.32), whereas no significant effect was observed for sleep quality. Subgroup analysis indicated that intervention duration accounted for 55.5% of the heterogeneity in anxiety outcomes. All studies were rated as having some concerns regarding risk of bias, primarily due to self-reported outcomes and lack of blinding. Certainty of evidence was moderate for anxiety and low for sleep quality. DISCUSSION: MBIs appear to be effective in reducing anxiety among patients with breast cancer; however, no significant effect was observed for sleep quality. All included studies were rated as having some concerns regarding risk of bias, and the limited reporting of adverse events represents a limitation of the evidence. In addition, substantial heterogeneity in sleep quality outcomes and the limited number of included RCTs restrict exploration of heterogeneity sources and limit generalizability. Further high-quality well-designed RCTs are needed to strengthen and confirm the evidence.

Female↗

PubMed1978

[Vigilance pattern and sleep quality under the effect of flunitrazepam].

Explore the source record for details and available documents.

Adult↗

PubMed1976

[Proceedings: Psychotropic drugs and quality of sleep: quantitative neurophysiological and subjective parameters (author's transl)].

The effect of drugs of the 3 main psychopharmaceutical classes (anxiolytics, neuroleptics, antidepressants) on objective and subjective sleep parameters was studied in healthy normal volunteers. Objective parameters included: computerclassified sleep stages, visually evaluated REM-activity as well as 22 variables of the quantitatively analyzed all-night sleep and REM-sleep EEG. Alterations of the subjective sleep quality were rated based on a sleep self-rating scale. It was found that anxiolytics, neuroleptics and antidepressants induce characteristic changes in the objective sleep parameters. Subjectively, the quality of sleep was best after anxiolytics, while the quality of awakening in the morning was dependent on the dose of the anxiolytic drug. Finally, the relationship between objective and subjective sleep parameters was explored.

Adult↗

PubMed1978

Relationship of arousal threshold to sleep stage distribution and subjective estimates of depth and quality of sleep.

The relationship of arousal threshold, amounts of various sleep stages, and subjective rating of sleep was studied in two separate experiments involving 7 and 26 young adult subjects, respectively. Electroencephalographic sleep stage data, subjective response data, and arousal threshold data were collected over a series of nights in the sleep laboratory. Only nonsignificant relationships were found between magnitude of arousal threshold and amounts of various sleep stages or subjective rating of sleep quality in between-subjects analyses. However, when the nights representing extremes in arousal threshold were examined within-subject, it was found that nights of high threshold were accompanied by subjective reports of significantly better sleep in both studies and by a significant decrease in the amount of stage W in one study. Arousal threshold was not related to subjective depth of sleep in either study. Rather, subjective ratings of depth of sleep were significantly related to the amount of EEG-defined wakefulness and stage 1.

Adolescent↗

PubMed2026

Efficacy of Proton Pump Inhibitor Therapy for Nocturnal GERD Symptoms and Associated Sleep Disturbances: A Systematic Review of Randomized Controlled Trials.

GOALS: A systematic review was conducted to evaluate the efficacy and safety of proton pump inhibitor (PPI) therapy in relieving nocturnal reflux symptoms and sleep disturbances. BACKGROUND: Nocturnal gastroesophageal reflux disease (GERD) is commonly associated with sleep disturbances. The benefits of PPI therapy for GERD-related nocturnal reflux and sleep disturbance remain unclear. STUDY: We searched the MEDLINE, EMBASE, and Cochrane CENTRAL databases from inception to March 1, 2026, for randomized controlled trials (RCTs) in adults with GERD and sleep disturbances that compared any PPI to placebo or an alternative therapy. The primary outcome was the proportion of patients experiencing relief from nighttime heartburn. Secondary outcomes included relief from GERD-related sleep disturbances, changes in subjective sleep quality, work productivity, and treatment-emergent adverse events (TEAEs). RESULTS: Five RCTs involving 1495 patients met the inclusion criteria. Three placebo-controlled trials consistently showed that PPI therapy improved nighttime heartburn relief and GERD-related sleep disturbances compared with placebo. Subjective sleep quality and sleep-related daytime functioning also generally improved with PPI therapy. However, the findings were more heterogeneous across trials because of differences in study populations, comparators, and outcome measures. Across the placebo-controlled studies, TEAEs were generally similar between the PPI and placebo groups. CONCLUSIONS: PPI therapy was associated with improvement in nighttime heartburn and reflux-related sleep disturbances, especially in patients with reflux-driven nocturnal symptoms. The available evidence also suggests potential improvement in subjective sleep quality and sleep-related daytime functioning.

Humans↗

PubMed2026

Comparative effectiveness and safety of pharmacological interventions for sleep outcomes in chronic non-cancer pain: a systematic review and network meta-analysis.

Sleep disturbances are highly prevalent among individuals with chronic non-cancer pain and are associated with worse pain severity and poorer prognosis. The comparative trade-offs between the effectiveness and safety of available pharmacotherapies for sleep outcomes in this population remain poorly defined. Ninety-eight RCTs involving 28,920 participants (mean age 53.2 years, 71.2% female) were included. Moderate-certainty evidence demonstrated that melatonin significantly improved sleep quality compared with placebo (standardized mean difference [SMD] = -0.60, 95%CI: -0.98, -0.22). Ten agents (e.g., amitriptyline, oxycodone, gabapentin, pregabalin, duloxetine) also showed statistically significant improvements in subjective sleep quality (SMD = -0.24 to -1.07), but most effects were supported by low-certainty evidence and were accompanied by an increased risk of adverse events (odds ratio [OR] = 1.90 to 37.00). Conversely, melatonin was not associated with an increased risk (OR = 0.88, 95%CI: 0.19, 3.94). Our findings indicate that melatonin shows promise as a safe, adjunctive option for improving sleep quality in this population, but larger, condition-specific trials are warranted to confirm these effects. Other pharmacological agents are limited by lower-certainty and unfavorable safety profiles. These results should be interpreted cautiously given limited direct comparisons, heterogeneous chronic pain populations, the high proportion of trials at high risk of bias, and the predominance of subjective sleep outcomes.

Humans↗

PubMed2026

Ginkgo biloba versus desmopressin in treatment of children with monosymptomatic nocturnal enuresis: A randomized controlled trial.

OBJECTIVE: To evaluate the efficacy and safety of Ginkgo biloba extract (GBE) compared with Desmopressin and their combination in children with monosymptomatic nocturnal enuresis (MNE). METHODS: In this double-blind, randomized, placebo-controlled trial, 398 children aged 5-14 years with MNE were assigned to four groups: placebo, GBE (60 mg daily), Desmopressin (0.2 mg daily), or GBE plus Desmopressin for 3 months. Primary outcomes included the number of wet nights per week. Secondary outcomes assessed sleep quality using the Sleep Disturbance Scale for Children (SDSC), arousal by the Disorders of Arousal (DA) score, and quality-of-life using the Pediatric Incontinence Questionnaire (PinQ). RESULTS: After 3 months, the combination group demonstrated the greatest improvement in wet nights (median 0 [IQR 0-2]) compared to GBE (6 [0.5-6.5]) and Desmopressin (2 [0-6]) (p < 0.001). Full response rates (≥90% reduction in wet nights) were highest with combination therapy (88.3%), followed by Desmopressin (46.5%), GBE (24.8%), and placebo (9.5%) (p < 0.001). GBE-containing groups showed significantly increased DA and SDSC scores, indicating enhanced arousal and lighter sleep. Quality-of-life (PinQ) score decreased in all treatment groups denoting improvement, with the best outcomes observed in the combination arm. Adverse effects were mild and comparable across groups, and serum sodium levels remained stable. CONCLUSION: GBE is a safe and effective novel therapy for MNE, improving sleep arousal and symptom control. Its combination with Desmopressin offers superior efficacy, better quality of life, and lower relapse rates than either agent alone.

Humans↗

PubMed2026

Effects of six weeks of guanidinoacetic acid supplementation with and without creatine monohydrate on cognitive function and markers of health in healthy adults.

BACKGROUND: Guanidinoacetic acid (GAA) supplementation has been reported to increase brain creatine content more effectively than creatine monohydrate (CrM). However, the effects on cognitive function are unclear. PURPOSE: The purpose of this proof-of-concept exploratory clinical trial was to determine whether GAA supplementation with and without CrM affects cognitive function and/or markers of health. METHODS: In a double-blind, randomized, and counterbalanced manner, 58 healthy and active adults (33 females, 35.5 ± 14 years, 76.2 ± 14 kg) ingested a PLA (PLA, 2 × 6 g/d maltodextrin), GAA (2 × 1 g/d) + PLA (2 × 5 g/d), or GAA (2 × 1 g/d) + CrM (2 × 5 g/d) for six weeks. The participants donated fasting blood samples and completed a battery of tests and questionnaires assessing various aspects of function, mood, stress, sleep quality, and markers of health at baseline and after six weeks of supplementation. Data were analyzed using General Linear Model (GLM) multivariate and univariate with repeated measures, and mean changes from baseline with 95% confidence intervals, and Chi-squared analysis, and considered significant when the probability of error was 0.05 or less, and approaching significance (p > 0.05-p < 0.10). RESULTS: GAA supplementation tended to improve overall reaction time (-241.8 ms [-533, 50], p = 0.10) while significant interaction effects were observed in overall reaction time (p = 0.031-330 ms [-629, -31]) and YES reaction time (-290 ms [-484, -96], p = 0.004) while recalled correct reaction time (-178 ms [-374, 21], p = 0.078) and recalled correct YES (7.4 % [-1, 15.8], p = 0.084) approached significance compared to PLA. Limited to no effects were observed on the Delayed Picture Recognition Task Test, Digit Vigilance Task Test, Corsi Block Task Test, or Stroop Color-Word Task Test. The amount of time engaged in moderate physical activity was significantly greater (p < 0.05) in the GAA group compared to PLA. Participants in the GAA group reported a lower frequency of controlling irritations (p = 0.036), and feeling like difficulties are mounting (p = 0.053) on the Perceived Stress Scale. Some positive and potentially undesirable effects were observed in sleep quality assessments. The quality of life assessment revealed that participants in the GAA group reported less frequent feelings of being worn out (p = 0.068) and that their health was excellent (p = 0.092) while those in the GAA + CrM group reported more frequent limitations when bending, kneeling, or stooping (p = 0.053), more often feeling full of life (p = 0.081), and less frequency in feeling downhearted and depressed (p = 0.066). No clinically meaningful changes were observed in blood markers or self-reported side effects among the groups. CONCLUSION: Dietary supplementation with GAA (2 g/d) and the combination of CrM (10 g/d + GAA 2 g/d) for six weeks improved delayed verbal episodic recognition memory and retrieval speed and some measures of perceived stress, sleep quality, and quality of life. However, most cognitive tests were not affected, particularly when comparing the GAA to the PLA group; there were some inconsistencies in the findings, and several differences only approached significance. Additional research is needed before conclusions can be drawn. Clinical trial registration: ISRCTN68542582.

Humans↗

PubMed2026

Diet and sleep among college student populations: a systematic review.

College students are at-risk for both poor diet and poor sleep. We aimed to systematically review the evidence regarding associations between diet and sleep health within this population. A comprehensive electronic search was conducted in PubMed, Embase, Scopus, Web of Science, and PsycINFO from the earliest possible date through February 6, 2026. A total of 57 studies representing 44 countries were retained; most were cross-sectional. There were 22 studies that examined dietary patterns in relation to sleep, generally showing that healthier diet patterns, including the Mediterranean Diet, were related to better sleep quality. Among 20 studies that examined individual foods or nutrients, there was evidence that fruits, vegetables, dairy, protein, and lower intake of sugar-sweetened beverages were linked to better sleep health, although some findings were mixed. Finally, 15 studies related meal timing to sleep quality, showing that breakfast skipping and later last meals were associated with poor sleep health. Overall, these studies reveal robust cross-sectional associations between diet and sleep among college students, but more longitudinal studies and randomized controlled trials are needed to evaluate directionality. Moreover, a key direction for future study is consideration of sleep and nutrition situated within the unique contexts of college settings and academic schedules.

Humans↗

PubMed1975

[Some indices of the activity of the brain in "rapid" sleep preceeded or not preceeded by delta-sleep].

In order to study the functional interaction between the delta sleep and the REM sleep some psychophysiological features of REM sleep were examined in REM-onset (without any preceding delta sleep--"early REM period") and in the REM period (REMP) terminating the normal sleep cycle (with the preceding delta sleep) of 92 daytime sleep attacks in 10 narcoleptic patients. Under these conditions the significant differences exist in the characteristics of the dream reports and in subjective estimations of sleep quality and duration. Sleep was evaluated as "superficial" and underestimations of sleep duration took place after an early REMP. Correct estimations of sleep duration and evaluations of sleep as "deep" dominated after REMP enging sleep cycles. The results obtained indicate the functional interaction between the delta sleep and REM sleep existing in the sleep cycle and largely determining the psychic content of the brain activity in the REM sleep.

Brain↗