The REM microarousal and REM duration as the potential indicator in paradoxical insomnia.

OBJECTIVE: Although paradoxical insomnia is a prevalent subtype of chronic insomnia, the etiology of it is unclear. Contrary to complaints of little or no sleep, polysomnography (PSG) findings show that paradoxical insomnia patients have near normal sleep macrostructure. The purpose of this study is to determine the changes of microstructure and explore the etiology of paradoxical insomnia. METHODS: The PSG findings of 89 paradoxical insomnia patients were compared with those of 41 gender balanced healthy controls without sleep complaints. All subjects underwent nocturnal PSG recordings. Conventional PSG measures and microarousals were quantified and statistically analyzed. Receiver operating characteristic curve and correlation analysis were used to evaluate the potential of REM sleep microarousals and REM duration as indicators of paradoxical insomnia. RESULTS: Compared with the controls, paradoxical insomnia patients had no significant differences in sleep macrostructures. Statistical analysis showed that non-rapid eye movement (NREM) microarousals revealed no significant differences between paradoxical insomnia patients and controls. Noticeably, more spontaneous microarousals appeared in rapid eye movement (REM) stage for paradoxical insomnia patients. Based on receiver operating characteristic curve (ROC), the optimal cutoff value of REM sleep microarousals could predict paradoxical insomnia. Furthermore, a positive correlation between microarousals in REM sleep and the duration of REM sleep was presented in paradoxical insomnia patients. CONCLUSIONS: The frequency of REM microarousals and the duration of REM sleep could reflect the real sleep state of paradoxical insomnia patients. That suggested PSG investigation extended to microarousal could be helpful to understand the etiology in paradoxical insomnia.

Discriminating Paradoxical and Psychophysiological Insomnia Based on Structural and Functional Brain Images: A Preliminary Machine Learning Study.

Insomnia disorder (ID) is a prevalent mental illness. Several behavioral and neuroimaging studies suggested that ID is a heterogenous condition with various subtypes. However, neurobiological alterations in different subtypes of ID are poorly understood. We aimed to assess whether unimodal and multimodal whole-brain neuroimaging measurements can discriminate two commonly described ID subtypes (i.e., paradoxical and psychophysiological insomnia) from each other and healthy subjects. We obtained T1-weighted images and resting-state fMRI from 34 patients with ID and 48 healthy controls. The outcome measures were grey matter volume, cortical thickness, amplitude of low-frequency fluctuation, degree centrality, and regional homogeneity. Subsequently, we applied support vector machines to classify subjects via unimodal and multimodal measures. The results of the multimodal classification were superior to those of unimodal approaches, i.e., we achieved 81% accuracy in separating psychophysiological vs. control, 87% for paradoxical vs. control, and 89% for paradoxical vs. psychophysiological insomnia. This preliminary study provides evidence that structural and functional brain data can help to distinguish two common subtypes of ID from each other and healthy subjects. These initial findings may stimulate further research to identify the underlying mechanism of each subtype and develop personalized treatments for ID in the future.

Polysomnographic Characteristics of the Patients Having Chronic Insomnia and Obstructive Sleep Apnea: Evidence for Paradoxical Insomnia and Comorbid Insomnia with OSA (COMISA).

Background: Sleep state misperception (SSM) is seen among patients with obstructive sleep apnea (OSA) as well as those having insomnia. Moreover, OSA and insomnia can also be comorbid. This study aims at finding the proportion of SSM and "Comorbid Insomnia with OSA" (COMISA) among patients of OSA and chronic insomnia. Macroachitecture of sleep was also compared across groups. Methods: This study utilized the retrospective laboratory and medical records of two groups of patients: chronic insomnia and OSA. Sleep disorders were diagnosed according to standard criteria. Daytime sleepiness was examined using the Epworth Sleepiness Scale. Diagnosis of SSM was based on the difference between subjective and objective sleep onset latency (Subjective SOL > 1.5 × Objective SOL). Results: Sixteen adult subjects were included in each group. Based on the difference between subjective and objective sleep onset latency, SSM was reported by 62.5% subjects of chronic insomnia and 56.25% subjects having OSA (OR = 1.29; 95% CI = 0.31-5.33; P = 0.79). The proportion of COMISA in subjects with chronic insomnia was 18% and among subjects with OSA, it was 43%. Effect size for the proportion was calculated as odds ratio (33.96; 95% CI = 7.48-154.01; P < 0.0002). Thus, the odds for COMISA were higher among subjects with OSA than those with chronic Insomnia. The three groups (OSA, COMISA and Chronic Insomnia) were comparable with regard to the macro-architecture of sleep. Conclusion: SSM is common among subjects with OSA and chronic insomnia. COMISA was commoner among patients with OSA compared to those with chronic insomnia. Macro-architecture of sleep is comparable among groups.

Negative and positive sleep state misperception in patients with insomnia: factors associated with sleep perception.

STUDY OBJECTIVES: In the present study, factors associated with sleep perception were identified by comparing clinical characteristics and polysomnographic variables between insomnia patients with negative and positive sleep state misperception (NSSM and PSSM, respectively). METHODS: Self-reported and objective sleep measures were retrospectively collected, including the Pittsburgh Sleep Quality Index (PSQI), Beck Depression Inventory, and a questionnaire on "morning feeling" after nocturnal polysomnography in 150 patients with insomnia. Based on the misperception index (MI), participants were classified into NSSM (MI > 0, n = 115) and PSSM (MI < 0, n = 35) groups. RESULTS: The PSSM group had more N3 sleep on nocturnal polysomnography than the NSSM group (P = .002). The NSSM group showed a higher PSQI score (P < .001), longer self-reported sleep-onset latency (SOL) (P = .001), and a greater SOL discrepancy (P = .001). Self-reported feelings of tiredness and morning awakenings in the morning were higher in the NSSM group (P = .029 and P = .038). The MI negatively correlated with a proportion of N3 sleep (P = .005) and positively correlated with PSQI (P < .001), morning awakenings (P = .01), self-reported SOL (P < .001), and SOL discrepancy (P < .001) in patients with insomnia. Multiple regression analysis showed that N3 sleep, PSQI, and morning awakenings were significantly associated with MI in patients with insomnia. CONCLUSIONS: The proportion of slow-wave sleep and self-reported measures may be associated with perception of sleep in patients with insomnia. Objective and self-reported characteristics of patients with insomnia should be carefully evaluated and managed because they may influence the perception of sleep. CITATION: Yoon G, Lee MH, Oh SM, Choi J-W, Yoon SY, Lee YJ. Negative and positive sleep state misperception in patients with insomnia: factors associated with sleep perception. J Clin Sleep Med. 2022;18(7):1789-1795.

Conscious experiences and high-density EEG patterns predicting subjective sleep depth.

What accounts for feeling deeply asleep? Standard sleep recordings only incompletely reflect subjective aspects of sleep and some individuals with so-called sleep misperception frequently feel awake although sleep recordings indicate clear-cut sleep. To identify the determinants of sleep perception, we performed 787 awakenings in 20 good sleepers and 10 individuals with sleep misperception and interviewed them about their subjective sleep depth while they underwent high-density EEG sleep recordings. Surprisingly, in good sleepers, sleep was subjectively lightest in the first 2 h of non-rapid eye movement (NREM) sleep, generally considered the deepest sleep, and deepest in rapid eye movement (REM) sleep. Compared to good sleepers, sleep misperceptors felt more frequently awake during sleep and reported lighter REM sleep. At the EEG level, spatially widespread high-frequency power was inversely related to subjective sleep depth in NREM sleep in both groups and in REM sleep in misperceptors. Subjective sleep depth positively correlated with dream-like qualities of reports of mental activity. These findings challenge the widely held notion that slow wave sleep best accounts for feeling deeply asleep. Instead, they indicate that subjective sleep depth is inversely related to a neurophysiological process that predominates in early NREM sleep, becomes quiescent in REM sleep, and is reflected in high-frequency EEG activity. In sleep misperceptors, this process is more frequently active, more spatially widespread, and abnormally persists into REM sleep. These findings help identify the neuromodulatory systems involved in subjective sleep depth and are relevant for studies aiming to improve subjective sleep quality.

Paradoxical Insomnia in a Frustrated Patient Treated With Hypnotics for Ten Years.

Insomnia remains a common complaint for which patients present to their primary care providers. The reflex response by most primary care providers to treat insomnia is by prescribing hypnotics. The most commonly prescribed hypnotic is a sedative, such as a benzodiazepine or a benzodiazepine receptor agonist (BRZA). Paradoxical insomnia is a subtype of insomnia described as a complaint of severe insomnia disproportional to the presence of objective sleep disturbance or daytime impairment. Previously known as sleep-state misperception, this subtype of insomnia is not well known among the primary care community. We present a case of a 60-year-old female who had been prescribed multiple hypnotics for over 10 years and presented to our sleep clinic frustrated due to failure of treatment with each medicine. She was eventually diagnosed with paradoxical insomnia after an evaluation of her sleep parameters. This was effectively treated with cognitive-behavioral therapy. This case report aims to raise awareness of this subtype of insomnia in patients at the primary care level and to help minimize the use of hypnotics.

Changes in sleep structure and sleep spindles are associated with the neuropsychiatric profile in paradoxical insomnia.

AIM: Sleep spindles have an important role in the pathophysiology and perception of sleep. We aimed to investigate the link between sleep spindles and microstructural architecture of sleep in regard to psychiatric characteristics in paradoxical insomnia. METHOD: A total of 40 participants (20 with paradoxical insomnia, 20 healthy controls) were included in the study. All participants were evaluated by somnologists and undergone a full-night polysomnography at sleep laboratory. In addition, psychiatric interview was made by the same psychiatrist, and questionnaires were performed to assess the dimensions of the personality such as the neuroticism or extroversion (Eysenck Personality Questionnaire, EPQR-A); to evaluate the tendency to exaggerate somatic perceptions (Somatosensory Amplification Scale, SSAS), somatic parts of dissociation (Somatoform Dissociation Questionnaire, SDQ-20), and somatization (Somatization Scale, SS); to measure participants' feelings about their health and disease anxiety (Health Anxiety Inventory, HAI-18), and the level of uncontrollable and persistent anxiety (Penn State Worry Questionnaire, PSWQ); to investigate the tendency to ruminative thinking (Ruminative Thought Style Questionnaire, RTSQ), alexithymia (Toronto Alexithymia Scale, TAS-20); and to define the presence and the severity of depressive symptoms (Beck Depression Inventory, BDI). RESULTS: The duration and frequency of the sleep spindles were similar between two groups, while the density was significantly decreased in paradoxical insomnia. The duration of sleep spindles, on the other hand, showed positive correlations with the extroversion dimension scores of EPQR-A and PSWQ scores. DISCUSSION: Sleep protective mechanisms are disturbed in paradoxical insomnia as shown by the lower density of sleep spindles. In addition, fast spindle activity is associated with the personality traits, characterized by an increase in the expression of feelings and the level of anxiety.

Extreme sleep state misperception: From psychopathology to objective-subjective sleep measures.

STUDY OBJECTIVES: We tested the hypothesis that patients with extreme sleep state misperception display higher levels of psychopathology and reduced quantitative estimation abilities compared to other patients with insomnia. Secondary aims included the evaluation of group differences in subjective self-reported quality of life and sleep quality and objective sleep parameters. METHODS: In this cross-sectional, observational study, 249 patients with insomnia underwent a video-polysomnography with a subsequent morning interview to assess self-reported sleep estimates and filled in a large battery of questionnaires. Patients were classified into High Misperception (HM) and Moderate Misperception (MM) groups, according to the complement of the ratio between self-reported total sleep time and objective total sleep time (Misperception Index). RESULTS: No significant differences emerged in any of the psychopathological measures considered between the HM and the MM group. Similarly, no effect was observed in quantitative estimation abilities. HM patients displayed a significantly increased number of awakenings per hour of sleep and a reduced dream recall rate. Their overall sleep quality and quality of life was significantly impaired. CONCLUSIONS: Future research on sleep misperception should focus on factors other than the level of psychopathology and estimation abilities, in particular sleep microstructure and quantitative EEG studies in both REM and NREM sleep.

Alterations of Subcortical Brain Structures in Paradoxical and Psychophysiological Insomnia Disorder.

Insomnia disorder (ID) is a common illness associated with mood and cognitive impairments. Subtyping ID is an ongoing debate in sleep medicine, but the underlying mechanisms of each subtype is poorly understood. Growing evidence suggests that subcortical brain structures play the key roles in pathophysiology of ID and its subtypes. Here, we aimed to investigate structural alteration of subcortical regions in patients with two common ID subtypes i.e., paradoxical and psychophysiological insomnia. Fifty-five patients and 49 healthy controls were recruited for this study and T1-weighted images and subjective and objective sleep parameters (i.e., Pittsburgh Sleep Quality Index and polysomnography) were collected from participants. Subcortical structures including the hippocampus, amygdala, caudate, putamen, globus pallidus, nucleus accumbens, and thalamus were automatically segmented in FSL. Volume and shape (using surface vertices) of each structure were compared between the groups, controlled for covariates, and corrected for multiple comparisons. In addition, correlations of sleep parameters and surface vertices or volumes were calculated. The caudate's volume was smaller in patients than controls. Compared with controls, we found regional shrinkage in the caudate, nucleus accumbens, posterior putamen, hippocampus, thalamus, and amygdala in paradoxical insomnia and shrinkage in the amygdala, caudate, hippocampus, and putamen in psychophysiological insomnia. Interestingly, comparing two patients groups, shape alteration in the caudate, putamen, and nucleus accumbens in paradoxical insomnia and shrinkage in the thalamus, amygdala, and hippocampus in psychophysiological insomnia were observed. Both subjective and objective sleep parameters were associated with these regional shape alterations in patients. Our results support the differential role of subcortical brain structures in pathophysiology of paradoxical and psychophysiological insomnia.

Personality profiles in paradoxical insomnia: a case-control study.

INTRODUCTION: Paradoxical insomnia (PARA-I) is a clinically challenging condition to diagnose and treat. Previous findings suggest that personality profiles of patients with PARA-I may be different from other subtypes of insomnia. Therefore, investigation of these profiles can be helpful in the clinical management of these patients. OBJECTIVE: The current study compares personality profiles of individuals with paradoxical insomnia (PARA-I), psycho-physiological insomnia (PSY-I), and normal sleepers (NS). MATERIAL AND METHODS: A cross-sectional case-control study was conducted in the Sleep Disorders Research Center of Kermanshah University of Medical Sciences, Kermanshah, Iran between 2015 and 2017. Patients with PARA-I (n=20), PSY-I (n=20), and NS (n=60) were matched for age, gender, education, and history of mental and/or physical illness and completed the Minnesota Multiphasic Personality Inventory (MMPI) short form. One-way analysis of variance (ANOVA) and the Kruskal-Wallis test were used to compare subscale means across groups. RESULTS: With the exception of the schizophrenia scale (P =.059), significant differences were found in all subscales of the insomnia groups compared to the NS group (P=.001). Compared to the NS group, patients with PARA-I showed significant differences in the hysteria and hypomania subscales (P<.05) and patients with PSY-I showed significant differences in the hysteria, hypochondriasis, and psychopathic subscales (P=.001). No significant differences were found between the PARA-I and PSY-I groups on any subscale. CONCLUSION: This study demonstrates that significant differences in the personality profiles on the MMPI exist between PARA-I and PSY-I patients compared to NS. These findings should inform the diagnosis and future treatment approaches for insomnia.

The paradox of paradoxical insomnia: A theoretical review towards a unifying evidence-based definition.

Paradoxical insomnia is one of the most intriguing yet challenging subtypes of insomnia. Despite being recognized for a long time by the international community, it is still unclear whether this entity really exists, which are its features and boundaries. Much of the debate is fuelled by the lack of a consensus on its precise definition. To help filling some of the existing gaps, a systematic review of the literature was conducted, through which 19 different quantitative definitions were obtained. These definitions were then applied to two distinct datasets. The first consisted of 200 chronic primary insomnia patients, diagnosed according to the DSM-IV-TR criteria. The second consisted of 200 age- and sex-matched healthy persons without insomnia. For each dataset, available data from the objective sleep parameters and their subjective estimation were imported and analysed in MATLAB. Depending on the definition used, the prevalence of paradoxical insomnia ranged from 8 to 66%, while agreement between different definitions ranged from -0.19 to 0.9 (using Cohen's kappa coefficient). Based on the results garnered, necessary features for a quantitative definition of paradoxical insomnia were identified. Several open questions remain, such as whether there is a minimum number of hours a patient should sleep to fulfill the criteria for a diagnosis of paradoxical insomnia, and whether sleep latency can be used in the definition along with total sleep time. We conclude by advocating continued study of paradoxical insomnia and sleep state misperception and by providing specific directions for future research. STATEMENT OF SIGNIFICANCE: The current understanding of paradoxical insomnia and, more broadly, of sleep state misperception, is greatly hampered by the lack of agreement on a quantitative and evidence-base measure of the discrepancy between subjective and objective sleep evaluation. The current study provides a critical analysis about the strength and the limitations of the available definitions, using both a data-driven and a theory-driven approach. The overarching goal is to motivate a rigorous discussion involving the main experts of the field, to build a consensus, and develop an evidence-based measure of sleep state misperception and/or of paradoxical insomnia.

Sleep EEG spectral power is correlated with subjective-objective discrepancy of sleep onset latency in major depressive disorder.

We aimed to identify the sleep electroencephalography (EEG) spectral power correlates of the subjective-objective discrepancy (SOD) of sleep onset latency (SOL) in major depressive disorder (MDD), primary insomnia (PI), and normal sleeping control (NSC) groups. We examined relative power values in standard frequency bands of the EEG spectra during the first Non-Rapid Eye Movement (NREM) sleep period as correlates of SOD of SOL between sleep diary and polysomnography in MDD (n = 36), PI (n = 19), and NSC (n = 23) groups. We also compared the relative spectral power of sleep EEG among MDD (n = 40), PI (n = 19), and NSC (n = 23) groups. SOD of SOL in MDD patients was positively correlated with relative sigma (r = 0.622, p corrected < 0.001), beta power (r = 0.559, p corrected = 0.002), and alpha power (r = 0.469, p corrected = 0.024) in the first NREM sleep period. There was no significant difference of sleep EEG power spectra among the three groups. SOD was positively correlated with high frequency EEG in MDD. High frequency EEG power is thought to be associated with hyperarousal and memory consolidation, and future larger-scale studies may further elucidate the neurophysiological mechanisms underlying SOD of sleep onset duration.

Anxiety and depression in paradoxical insomnia: a case-control study.

PURPOSE: To compare anxiety and depression among patients with paradoxical insomnia (Para-I), patients with psychophysiological insomnia (Psy-I), and normal sleepers (NS). PATIENTS AND METHODS: A cross-sectional case-control study was conducted in patients with Para-I (n=63), patients with Psy-I (n=63), and NS (n=63) from southwest China. The three groups were matched for age (mean age: 42.0±10.30 years), gender (per group: male =22; female =41), educational level, and nature of occupation. Anxiety and depression were evaluated using the Self-Rating Anxiety Scale and Self-Rating Depression Scale and compared among the groups. RESULTS: Concerning anxiety, patients with Para-I had a significantly higher mean Self-Rating Anxiety Scale score (P<0.05) and significantly higher incidence of anxiety compared to NS (P<0.0167). There were no significant differences between the two insomnia groups on anxiety measures. Concerning depression, patients with Para-I had a significantly higher mean Self-Rating Depression Scale score than patients with Psy-I and NS (both, P<0.05), as well as a significantly higher incidence of moderate to severe depression than in the Psy-I group and NS (both, P<0.0167). CONCLUSION: Both Psy-I and Para-I patients had significantly higher anxiety and depression than NS. Compared to Psy-I, Para-I patients had slightly (but not significantly) lower anxiety and significantly higher depression.

Paradoxical insomnia and subjective-objective sleep discrepancy: A review.

Paradoxical insomnia is characterized by discrepancy between subjective and objective assessments of sleep and is challenging to diagnosis and treat. Typically, polysomnographic (PSG) findings show significantly longer total sleep time than patients' report of sleep, and the difference between subjective and PSG sleep is greater than that seen in other insomnia subtypes. Subjective-objective sleep discrepancy may also present in different clinical pictures, as marked discrepancies between patients' perception of sleep and objective findings are common in a variety of medical, sleep and psychiatric disorders. However, there is a paucity of literature about the etiology and treatment of sleep discrepancy and paradoxical insomnia. Therefore, the underlying neurophysiological mechanisms of sleep discrepancy and paradoxical insomnia should be further investigated. Additionally, well-controlled clinical trials are needed to establish an evidence based intervention for treatment.

Personal characteristics of paradoxical insomnia: A case-control study / 中南大学学报(医学版)

Objective:To compare the personal characteristics between the patients with paradoxical insomnia and the patients with primary insomnia or the normal sleepers.Methods:A case-control study with the proportion at 1∶1∶1 was carried out.The patients with paradoxical insomnia were diagnosed in Sleep Medicine Center of West China Hospital of Sichuan University between March 2013 and December 2013.A case of paradoxical insomnia was matched with two controls:a primary insomnia patient and a normal sleeper.A total of 63 matched cases were collected.A face-to-face survey was conducted by using the following scales:General Data Scale and Eysenck Personality Questionnaire (EPQ).Results:The average scores of psychoticism,extraversion,and neuroticism for paradoxical insomnia cases were (52.1±10.2),(49.6±9.8),and (56.0±12.0),respectively.In general,31.7% of paradoxical insomnia patients had psychoticism or psychoticism tendency in their personality,which were more obvious than those in primary insomnia patients (7.9%) (x2=l 1.228,p0.0125).Conclusion:The personal characteristics for paradoxical insomnia patients did not reached obviously abnormal level.However,their psychoticism tendency,extroversion tendency and neuroticism tendency needed to be paid attention.

Sleep disturbances, TBI and PTSD: Implications for treatment and recovery.

Post-Traumatic Stress Disorder (PTSD), traumatic brain injury (TBI), and sleep problems significantly affect recovery and functional status in military personnel and Veterans returning from combat. Despite recent attention, sleep is understudied in the Veteran population. Few treatments and rehabilitation protocols target sleep, although poor sleep remains at clinical levels and continues to adversely impact functioning even after the resolution of PTSD or mild TBI symptoms. Recent developments in non-pharmacologic sleep treatments have proven efficacious as stand-alone interventions and have potential to improve treatment outcomes by augmenting traditional behavioral and cognitive therapies. This review discusses the extensive scope of work in the area of sleep as it relates to TBI and PTSD, including pathophysiology and neurobiology of sleep; existing and emerging treatment options; as well as methodological issues in sleep measurements for TBI and PTSD. Understanding sleep problems and their role in the development and maintenance of PTSD and TBI symptoms may lead to improvement in overall treatment outcomes while offering a non-stigmatizing entry in mental health services and make current treatments more comprehensive by helping to address a broader spectrum of difficulties.

Positive Sleep State Misperception Mimicking Hypersomnia

A condition of underestimation of sleep is classified as paradoxical insomnia or sleep state misperception. However, overestimation of sleep, so called positive sleep state misperception has not been clearly described. Here we report a middle-aged woman with positive sleep state misperception who presented excessive sleepiness mimicking hypersomnia.

Insomnia and sleep misperception.

Sleep misperception is often observed in insomnia individuals (INS). The extent of misperception varies between different types of INS. The following paper comprised sections which will be aimed at studying the sleep EEG and compares it to subjective reports of sleep in individuals suffering from either psychophysiological insomnia or paradoxical insomnia and good sleeper controls. The EEG can be studied without any intervention (thus using the raw data) via either PSG or fine quantitative EEG analyses (power spectral analysis [PSA]), identifying EEG patterns as in the case of cyclic alternating patterns (CAPs) or by decorticating the EEG while scoring the different transient or phasic events (K-Complexes or sleep spindles). One can also act on the on-going EEG by delivering stimuli so to study their impact on cortical measures as in the case of event-related potential studies (ERPs). From the paucity of studies available using these different techniques, a general conclusion can be reached: sleep misperception is not an easy phenomenon to quantify and its clinical value is not well recognized. Still, while none of the techniques or EEG measures defined in the paper is available and/or recommended to diagnose insomnia, ERPs might be the most indicated technique to study hyperarousal and sleep quality in different types of INS. More research shall also be dedicated to EEG patterns and transient phasic events as these EEG scoring techniques can offer a unique insight of sleep misperception.

Sleep-wake misperception in sleep apnea patients undergoing diagnostic versus titration polysomnography.

OBJECTIVE: Insomnia is commonly co-morbid with obstructive sleep apnea. Among patients reporting insomnia symptoms, sleep misperception occurs when self-reported sleep duration under-estimates objective measures. Misperception represents a clinical challenge since insomnia management is based entirely on patient self-report. We tested the hypothesis that misperception occurring in sleep apnea patients would improve with subsequent treatment. METHODS: We compared subjective sleep-wake reports with objective sleep in adults with obstructive sleep apnea (n=405) in two nights of polysomnography (diagnostic and treatment) within a median interval of 92 days. RESULTS: Sleep latency was generally over-estimated, while wake after sleep onset and number of awakenings were under-estimated. None of these estimations differed between diagnostic and treatment polysomnograms. We observed a large spectrum of total sleep time misperception values during the diagnostic polysomnogram, with one third of the cohort under-estimating their total sleep time by at least 60 min. Of those with >60 minute misperception, we observed improved total sleep time perception during treatment polysomnography. Improved perception correlated with improvements in self-reported sleep quality and response confidence. We found no polysomnogram or demographic predictors of total sleep time misperception for the diagnostic polysomnogram, nor did we find objective correlates of improved perception during titration. CONCLUSION: Our results suggest that misperception may improve with treatment of obstructive sleep apnea in patients who also exhibit misperception. Within subject changes in misperception are consistent with misperception being, at least to some extent, a state characteristic, which has implications for management of patients with comorbid insomnia and sleep apnea.

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

The objectives of the study were to examine EEG activities using power spectral analysis (PSA) of good sleepers (GS), psychophysiological (PsyI) and paradoxical (ParI) insomnia sufferers on two consecutive nights. Participants completed three nights of PSG recordings in a sleep laboratory following a clinical evaluation. Participants were 26 PsyI, 20 ParI and 21 GS (mean age=40 years, SD=9.4). All sleep cycles of Nights 2 and 3 were retained for PSA. The absolute and relative activity in frequency bands (0.00 to 125.00 Hz) were computed at multiple frontal, central and parietal sites in REM and NREM sleep. Mixed model ANOVAs were performed with absolute and relative PSA data to assess differences between groups and nights. Over the course of the two nights, more absolute delta activity at F3, C3, and P3 was observed in ParI compared with PsyI suggesting deactivation of the left hemisphere in ParI and/or hyperactivation in PsyI. Further analysis on absolute PSA data revealed that differences between groups relate mostly to NREM. In REM, lower relative activity in slower frequency bands was found in ParI in comparison with GS and less relative theta activity was found in PsyI compared with GS implying higher activation in insomnia. In addition, between nights variability has been found in absolute powers of faster frequency bands (beta to omega). Signs of decreased cortical activity in absolute PSA in NREM combined with increased relative cortical activation in REM were found in ParI which might contribute to the misperception of sleep in ParI.