Parasomnias

STUDY OBJECTIVES: This work assesses the prevalence and development of disturbing dreams among adolescents and the association of these dreams with anxiety. DESIGN: Sex differences in prevalence were analyzed with chi-square analyses. Changes over time were assessed with Wilcoxon tests and cross-tabulation tables. Associations with anxiety and DSM-III-R symptoms were assessed with ANOVA designs. SETTING: N/A PARTICIPANTS: A total of 610 boys and girls rated their recall of disturbing and normal dreams at both 13 and 16 years of age. Subgroups of subjects were evaluated for anxiety symptoms at age 13 and for DSM-III-R symptoms of separation anxiety (SA), overanxious disorder (OD) and generalized anxiety disorder (GAD) at age 16. INTERVENTIONS: N/A MEASUREMENTS AND RESULTS: The recall of disturbing dreams was more prevalent for girls than for boys at both ages, and increased over time for girls while it decreased for boys. The recall of normal dreams was also more prevalent for girls at both ages, but this difference could not fully account for the difference in recall of disturbing dreams. Normal dream recall increased from age 13 to 16 for both sexes. The frequent occurrence of disturbing dreams was associated with anxiety at age 13 and with GAD, SA and OD symptoms at age 16 for both sexes. Evidence of more numerous OD symptoms for girls with frequent disturbing dreams suggests that this form of anxiety may partially account for the observed sex difference in disturbing dream prevalence. CONCLUSIONS: The findings highlight a prevalence of disturbing dreams that is especially marked for adolescent girls. Unlike previous cross-sectional studies, which have found the same sex difference, this longitudinal design also calls attention to within-subjects changes in disturbing dream recall. The results also confirm that the frequent recall of disturbing dreams is associated with pathological symptoms of trait anxiety-apparently even as young as 13 years of age. Further study of disturbing dreams may contribute to understanding of associated pathophysiological factors which, too, vary by sex (e.g., PTSD, insomnia, depression).

Angelman syndrome is a neurogenetic condition characterized by developmental delay, absence of speech, motor impairment, epilepsy and a peculiar behavioral phenotype that includes sleep problems. It is caused by lack of expression of the UBE3A gene on the maternal chromosome 15q11-q13. Although part of the diagnostic description, 'sleep problems' are not well characterized. A pattern emerges from the available reports. It includes reduced total sleep time, increased sleep onset latency, disrupted sleep architecture with frequent nocturnal awakenings, reduced rapid eye movement (REM) sleep and periodic leg movements. Poor sleep does not significantly interfere with daytime alertness and sleep problems commonly diminish by late childhood, with continuing improvement through adolescence and adulthood. Sleep problems in Angelman syndrome reflect abnormal neurodevelopmental functioning presumably involving dysregulation of GABA-mediated inhibitory influences in thalamocortical interactions. Management may be difficult, particularly in young children; it primarily involves behavioral approaches, though pharmacological treatment may be required. The relationship between sleep and seizure disorder, and between sleep and learning raises critical questions, but more studies are needed to address these relationships adequately.

We tested the hypothesis that weekday bedtime use of six technologies would be significantly associated with eight sleep parameters studied relating to sleep quantity, sleep quality, and parasomnias. In our cross-sectional study, we previously administered validated age-appropriate questionnaires (School Sleep Habits Survey, Technology Use Questionnaire). Participating adolescents (n=738; 54.5% boys) were aged 11-13 years and were from the Midlands region of the United Kingdom in 2010. Frequent use of all technology types was significantly inversely associated with weekday sleep duration (hours). Frequent music listeners and video gamers had significantly prolonged sleep onset (β=7.03 [standard error {SE}, 2.66]; P<.01 and β=6.17 [SE, 2.42]; P<.05, respectively). Frequent early awakening was significantly associated with frequent use of all technology types. The greatest effect was observed in frequent television viewers (odds ratio [OR], 4.05 [95% confidence interval {CI}, 2....

Purpose Catathrenia (nocturnal groaning) is a rare and relatively little-understood parasomnia. The characteristics of the sound and the recordings are not similar in all the relevant research papers. Indeed, there is currently some discussion regarding whether or not this is a single entity. For some authors, catathrenia is a particular form of parasomnia; for others, it may be a variant of snoring or a respiratory problem. The goal is to establish whether or not catathrenia may be regarded as an expiratory vocal sound. An attempt was made to classify the origin of this sound according to its sound structure. Methods We present the sound analysis of two patients, a man and a woman, with clinically diagnosed catathrenia and we compared them with the analysis of snoring. We use the spectrogram and the oscillogram. We classified the sounds according to the Yanagihara criteria. Results The vocal nature of the sound was confirmed, and several significant differences to some snoring sounds were discovered. The analysis of the catathrenia samples demonstrated that these signals are type II according to Yanagihara classification; these signals had a very short jitter, and had formants and harmonics. However, snoring is a type III, very irregular and had formants but not harmonics. Conclusions The oscillogram and the spectrogram in these patients show that the origins of the sounds are clearly different: catathrenia is laryngeal, while snoring is guttural. Catathrenia cannot be considered as expiratory snoring.

Resumen El sueño es un proceso muy importante para todo ser humano. Éste se divide en cuatro etapas una de las cuales es importante para el tema de la parálisis del sueño, siendo esta la etapa REM, donde la actividad cerebral es muy activa. La parálisis del sueño es una parasomnia que se caracteriza por la nula movilización muscular más que la de los ojos y el estar consciente de lo que sucede alrededor nuestro, situación en que muchas veces se presentan alucinaciones. Por otro lado, algunas de las causas que se creen puede influir en la presencia de ésta parálisis es la posición al dormir y el estrés tanto laboral como el trastorno de estrés postraumático. Palabras clave: Parálisis del sueño, alucinaciones, movimientos oculares rápidos, etapas del sueño, causas posibles.

Purpose: To test the usefulness of the FLEP scale in diagnosing nocturnal frontal lobe epilepsy (NFLE), arousal parasomnias, and REM sleep behavior disorder (RBD). Methods: The FLEP scale was applied to 71 subjects (60 male; 11 female; aged 54 ± 21) referred to an outpatient's sleep and epilepsy unit for diagnostic assessment of nocturnal motor-behavioral episodes, which turned to be arousal parasomnias (11 subjects), NFLE (14 subjects), or idiopathic RBD (46 subjects), based on the findings of in-lab full night video polysomnography with extended EEG montages. Results: The sensitivity of the scale as a diagnostic test for NFLE was 71.4%, the specificity 100%, the positive predictive value 100%, and the negative predictive value 91.1%. The FLEP scale gave an incorrect diagnosis in 4/71 (5.6%) of the cases, namely NFLE patients with episodes of nocturnal wandering, and uncertain diagnostic indications in 22/71 subjects (30.9%).

Nightmares are a prevalent parasomnia associated with a range of psychiatric conditions and pathological symptoms. Current knowledge about how nightmares are produced is still influenced by neo-psychoanalytic speculations as well as by more recent personality, evolutionary and neurobiological models. A majority of these models stipulate some type of emotionally adaptive function for dreaming, e.g., image contextualization, affect desomatization, mood regulation or fear extinction. Nightmares are widely seen to be either an intensified expression of an emotionally adaptive function or, conversely, as evidence of its breakdown. Our recent, affective network dysfunction (AND) model, integrates the tenets of many prior models in proposing that nightmares reflect problems with the fear extinction function of dreaming. This new model accounts for a wide range of dysphoric dream imagery (bad dreams, idiopathic nightmares, post-traumatic nightmares) and incorporates recent findings in the areas of brain imaging, sleep physiology, PTSD, anxiety disorders and the consolidation and extinction of fear memories.

This review attempts to assemble the characteristics of a distinct variant of sleepwalking called sexsomnia/sleepsex from the seemingly scarce literature into a coherent theoretical framework. Common features of sexsomnia include sexual arousal with autonomic activation (e.g. nocturnal erection, vaginal lubrication, nocturnal emission, dream orgasms). Somnambulistic sexual behavior and its clinical implications, the role of precipitating factors, diagnostic, treatment, and medico-legal issues are also reviewed. The characteristics of several individuals described in literature including their family/personal history of parasomnia as well as the abnormal behaviors occurring during sleep are reported.

Faithful replication of normal sleep through medications-can it be achieved? Departure from normal sleep with the use of drugs-when is it desired? Answers to these questions depend on accurate understanding of sleep and on concrete criteria upon which to define it. Since these elements are evolving sciences, as yet incompletely known, one might take a nihilistic approach that we simply cannot judge whether we have successfully replicated sleep, since we do not fully grasp what sleep is or what it does. To address these potential obstacles, our article is written in two sections. The first addresses theoretical considerations for how medications might be seen in the larger framework of sleep. The purpose of this section is to inform readers about key issues in evaluating whether a drug has sufficient data to persuasively argue it is re-creating sleep. (We hope that researchers interested in conducting studies, or critical readers of the drug-study literature, might find this section particularly useful.) The second section of this article approaches exemplary, current concepts of pharmacologic manipulation of sleep, organized by disorders as articulated by the International Classification of Sleep Disorders . This second section will combine practical knowledge of clinical sleep medicine, with emphasis on contemporary knowledge about molecular mechanisms that are felt to underlie some of these phenomena. We recognize that our collective knowledge about sleep will advance in the coming years. We hope that this article serves to facilitate that advance.

To describe a distinct parasomnia involving sexual behaviour, which we have named sexsomnia. We have used a case series as a basis for the description of sexsomina. Eleven patients with distinct behaviours of the sexual nature during sleep are described. The features in common with other nonrapid eye movement arousal parasomnias, such as sleepwalking are documented. Some patients had simply been referred to a tertiary sleep clinic for investigation of unrelated sleep problems. A small number had been involved in medicolegal issues. Sexsomnia has some distinct features that separate it from sleepwalking. The automatic arousal is more prominent, motor activities are relatively restricted and specific, and some form of dream mentation is often present. A significant number of patients with this unusual parasomnia behaviour were identified only after specific questions were asked, suggesting that the behaviour is more common than previously thought.

Resumo Resumo Resumo Resumo Casos de comportamento violento (CV) durante o sono são relatados na literatura. A incidência de comportamento violento durante o sono não é muito conhecida. Um estudo epidemiológico mostra que cerca de 2% da população geral apresentava comportamento violento dormindo e eram predominantemente homens. Neste artigo, os autores descrevem aspectos clínicos e médico-legais envolvidos na investigação do comportamento violento. O comportamento violento se refere a ferimentos autoinfligidos ou infligidos a um terceiro durante o sono. Ocorre, muito freqüentemente, seguindo um despertar parcial no contexto de um transtorno de despertar (parassonias). Os transtornos do sono predominantes diagnosticados são: transtorno de comportamento REM e sonambulismo. O comportamento violento poderia ser precipitado pelo estresse, uso de álcool e drogas, privação do sono ou febre.

Los trastornos del sueño son una patología muy frecuente tanto aislada, propia como tal, o asociada a otros trastornos. Sin embargo, es una parte de la medicina relativamente nueva, dado que ha sido en los últimos 40 años cuando se ha trabajado realmente en ella, y se han producido los avances tanto diagnósticos como terapéuticos. Las clasificaciones de estas enfermedades han ido sufriendo cierta evolución, fijándose primero en los síntomas, y luego en las enfermedades. La nueva clasificación del 2005 vuelve a basarse en los síntomas. En ella se incluyen más de 90 enfermedades del sueño, y se intentan incluir tanto los síntomas, como las enfermedades propiamente del sueño y aquellas en las que los trastornos del sueño son fundamentales. Conocer y dominar esta completa clasificación es esencial para poder manejar adecuadamente estos pacientes.

We describe a peculiar parasomnia observed in four Costello infants, characterized by periodic rhythmic movements of the tongue. Ten Costello patients (4 male; age range 9 months to 29 years) underwent 1 full-night laboratory-based video polysomnography. The four youngest patients (2 male and 2 female; age range 9 -31 months) presented during sleep repeated stereotyped movements of the tongue, producing a sucking-like or licking-like movement, mostly during non-rapid eye movement (NREM) sleep. Rhythmic tongue movements in Costello syndrome show the features of an NREM sleep parasomnia. Tongue movements during sleep probably originate from brainstem structures and could be facilitated by an impaired control of the oropharyngeal and tongue muscles.

Purpose This study aims to report on catathrenia occurring in narcolepsy with cataplexy (NC) patients under sodium oxybate (SO) treatment. Catathrenia is a parasomnia characterized by groaning and an abnormal respiratory pattern during sleep. Methods Fifty-one patients with NC and starting SO therapy underwent a baseline overnight polysomnography (PSG) to detect any sleep-related breathing disorders (SRBD). To avoid risks due to a possible central respiratory control depression by SO, all patients with concomitant obstructive sleep apnea (OSA) were treated with a nasal continuous positive airway pressure (nCPAP) device. After 2 months of treatment with SO, all patients underwent a follow-up overnight PSG to investigate possible newly occurring SRBD. They also underwent a semi-structured clinical interview to monitor other potential SO side effects. Results At baseline, four out of 51 patients showed simple snoring, and eight, mild to severe OSA. After a titration PSG night, patients with OSA received a nCPAP device. After 2 months of SO treatment, 28 patients (54.9%) showed SO-related side effects, including SRBD in 11 (21.6%). The follow-up PSG showed a respiratory pattern characteristic of catathrenia in seven patients (13.7%) as a newly observed and possibly benign SO side effect, and ruled out a worsening of OSA. Conclusions Catathrenia should be considered a possible side effect in NC patients under SO treatment and should be accurately identified to prevent unnecessary SO withdrawal.

Objective: The majority of women develop sleep impairments during pregnancy, but alterations in dream experiences remain poorly understood. This study aimed to assess prospectively and comparatively the recall of dreaming and of disturbed dreaming in late pregnancy. Methods: Fifty-seven nulliparous, third-trimester pregnant women (mean age ± SD, 28.7 ± 4.06 years) and 59 non-pregnant controls (mean age ± SD, 26.8 ± 4.21 years) completed demographics and psychological questionnaires. A 14-day prospective home log assessed sleep and dream characteristics and the Sleep Disorders Questionnaire measured retrospective dream and disturbed dream recall. Results: Even though pregnant and non-pregnant women showed similar prospective dream recall (P = 0.47), pregnant women reported prospectively more bad dreams (P = 0.004). More pregnant women (21%) than non-pregnant women (7%) reported a nightmare incidence exceeding moderately severe pathology (>1/week) (P = 0.03). Pregnant women also reported overall lower sleep quality (P = 0.007) and more night awakenings (P = 0.003). Higher prospective recall of bad dreams (r = À0.40, P = 0.002) and nightmares (r = À0.32, P = 0.001) both correlated with lower sleep quality in pregnant women. Conclusions: Late pregnancy is a period of markedly increased dysphoric dream imagery that may be a major contributor to impaired sleep at this time. Further polysomnographic assessments of pregnant women are needed to clarify relationships between sleep and disturbed dream production in this population.

Recibido el 13 de abril de 2010; aceptado el 18 de septiembre de 2010 Accesible en línea el 19 de noviembre de 2010 PALABRAS CLAVE Ictus; Sueño; Apnea; Parasomnia; Insomnio; Ritmo circadiano; Hipersomnia; Movimiento periódico de las piernas Resumen Introducción: Los ictus son una causa importante de morbimortalidad en la población actual.

Objectives. This study examines the prevalence and developmental changes of parasomnias and assesses gender differences, relationships between parasomnias, and associations with anxiety and family adversity using data collected during the course of a longitudinal study of a representative sample of children from Québec.

Nightmares and other common disturbances of dreaming involve a perturbation of emotional expression during sleep. Nightmares, the most prevalent dream disturbance, are now recognized as comprising several dysphoric emotions, including especially fear, although some argue that existential (or grief) dreams should be considered a separate entity. A genetic basis for nightmares has been demonstrated and their pathophysiology involves a surprising underactivation of the sympathetic nervous system in many instances. Personality factors, such as nightmare chronicity and distress and coping styles are mediating determinants of their clinical severity, as are drug and alcohol use. Many treatments have been described, with much support for the effectiveness of shortterm cognitive and behavior interventions such as systematic desensitization and imagery rehearsal. Several related dream disturbances occur at the transitions into or out of sleep and involve dysphoric emotions ranging from malaise to fear to frank terror. These disturbances include sleep starts, terrifying hypnagogic hallucinations, sleep paralysis, somniloquy with dream content, false awakenings, and disturbed lucid dreaming. The distinctive nature of these disturbances may be mediated by immediately preceding waking state processes (e.g., consciousness, sensory vividness) that intrude upon or carry over into dreaming.

STUDY OBJECTIVES: This work assesses the prevalence and development of disturbing dreams among adolescents and the association of these dreams with anxiety. DESIGN: Sex differences in prevalence were analyzed with chi-square analyses. Changes over time were assessed with Wilcoxon tests and cross-tabulation tables. Associations with anxiety and DSM-III-R symptoms were assessed with ANOVA designs. SETTING: N/A PARTICIPANTS: A total of 610 boys and girls rated their recall of disturbing and normal dreams at both 13 and 16 years of age. Subgroups of subjects were evaluated for anxiety symptoms at age 13 and for DSM-III-R symptoms of separation anxiety (SA), overanxious disorder (OD) and generalized anxiety disorder (GAD) at age 16. INTERVENTIONS: N/A MEASUREMENTS AND RESULTS: The recall of disturbing dreams was more prevalent for girls than for boys at both ages, and increased over time for girls while it decreased for boys. The recall of normal dreams was also more prevalent for girls ...

Objective: To estimate lifetime and current prevalence (defined as having experienced the specific parasomnia at least once during the last 3 months) of different parasomnias in the general population. In addition, to study the relationship between the different parasomnias and gender, depressive mood, and symptoms of sleep apnea, insomnia and restless legs, as well as estimating the prevalence of having multiple parasomnias. Methods: Population based cross-sectional study. One thousand randomly selected adults (51% female), 18 years and above, participated in a telephone interview in Norway. Results: Lifetime prevalence of the different parasomnias varied from about 4% to 67%. For sleep walking lifetime prevalence was 22.4% and current prevalence 1.7%. For the other parasomnias, lifetime and current prevalence were as follows: sleep talking 66.8% and 17.7%, confusional arousal 18.5% and 6.9%, sleep terror 10.4% and 2.7%, injured yourself during sleep 4.3% and 0.9%, injured somebody else during sleep 3.8% and 0.4%, sexual acts during sleep 7.1% and 2.7%, nightmare 66.2% and 19.4%, dream enactment 15.0% and 5.0%, sleep related groaning 31.3% and 13.5%, and sleep-related eating 4.5% and 2.2%. Depressive mood was associated with confusional arousal, sleep terror, sleep-related injury, and nightmare. There were few associations between the parasomnias and gender and symptoms of sleep apnea, insomnia, and restless legs, respectively. About 12% reported having five or more parasomnias.

Benign neonatal sleep myoclonus is a non-epileptic disorder. This phenomenon of the first weeks of life is characterized by erratic myoclonic jerks occurring only during sleep and with no electroencephalographic changes. It is not associated with perinatal complications, disappears spontaneously within two to four months, and it does not compromise future development. We illustrate with a video this relatively frequent condition, which is often misdiagnosed as epileptic in nature, and discuss the clinical characteristics and differential diagnosis. [Published with video sequences].

Nocturnal frontal lobe epilepsy (NFLE) is characterized by seizures with complex, often bizarre, violent behaviour arising only or mainly during sleep. These unusual seizures and their occurrence during sleep are often accompanied by normal EEG tracings and neuroradiological findings, making it difficult to distinguish NFLE seizures from other non-epileptic nocturnal paroxysmal events, namely parasomnias. NFLE was described for the first time in 1981, but, as its epileptic origin was controversial, the condition was called nocturnal paroxysmal dystonia. Even though many aspects of parasomnias and NFLE have been clarified in the last two decades, the problem of differential diagnosis remains a challenge for clinicians. This paper discusses some controversial points still under debate. The difficulties in distinguishing nocturnal epileptic seizures from parasomnias reflect just one aspect of the intriguing issue of the pathophysiological relationships between all types of paroxysmal m...

Benign neonatal sleep myoclonus is a non-epileptic disorder. This phenomenon of the first weeks of life is characterized by erratic myoclonic jerks occurring only during sleep and with no electroencephalographic changes. It is not associated with perinatal complications, disappears spontaneously within two to four months, and it does not compromise future development. We illustrate with a video this relatively frequent condition, which is often misdiagnosed as epileptic in nature, and discuss the clinical characteristics and differential diagnosis. [Published with video sequences].

Hyperkinetic seizures are considered a typical manifestation of nocturnal frontal lobe epilepsy (NFLE). Patients with temporal lobe epilepsy with mainly sleeprelated seizures have been described; however they commonly lack hyperkinetic activity and seizure frequency is low. We retrospectively analysed our population of 442 consecutive patients surgically treated between January 1996 and January 2004. Among these there were 25 patients with sleep-related hyperkinetic epileptic seizures, with a frontal lobe onset in 18 cases and a temporal lobe onset in 7. Patients with sleep-related hyperkinetic seizures with temporal lobe origin had anamnestic and clinical features strikingly similar to those with a frontal onset, with agitated movements, high seizure frequency and no history of febrile convulsions. We confirm our previous findings that this kind of epileptic manifestation is not only peculiar to frontal lobe epilepsy.

To describe a distinct parasomnia involving sexual behaviour, which we have named sexsomnia. We have used a case series as a basis for the description of sexsomina. Eleven patients with distinct behaviours of the sexual nature during sleep are described. The features in common with other nonrapid eye movement arousal parasomnias, such as sleepwalking are documented. Some patients had simply been referred to a tertiary sleep clinic for investigation of unrelated sleep problems. A small number had been involved in medicolegal issues. Sexsomnia has some distinct features that separate it from sleepwalking. The automatic arousal is more prominent, motor activities are relatively restricted and specific, and some form of dream mentation is often present. A significant number of patients with this unusual parasomnia behaviour were identified only after specific questions were asked, suggesting that the behaviour is more common than previously thought.

Background: Sleep disorders (SD) are one of the most frequent non-motor manifestations of Parkinson's disease (PD). Recent studies showed that SD may precede the onset of PD. Objectives: We reviewed current literature concerning 1) the incidence of PD among subjects with SD; and 2) the occurrence and possible clinical correlations of SD during the course of PD. Methods: A Medline search found 17 longitudinal studies. Results: The incidence of PD among patients with rapid eye-movement sleep behavioural disorders ranged from 20% to 65% of cases, within a wide interval of time (range: 2.2e13.3). The incidence of SD during PD progressively increased with disease duration in population-based studies but presented marked fluctuations in clinical based studies. Older age, male gender, dopaminergic treatment with higher dosage, cognitive impairment and hallucinations were associated with the onset of SD during PD. In the only population-based study among Japanese men excessive daytime sleepiness was associated with a threefold increased risk of developing PD. Conclusions: Available data suggest that SD could be the heralding clinical manifestation or a risk factor for PD onset. The prevalence of SD increases during the course of the PD and may be related to specific phenotype and rapid progression of PD. However, the current data are limited because of limited sample size and poor study design; prospective studies with larger sample size are warranted.

Purpose: To better understand the nature of the focal spike-wave discharges (FSWDs) and focally led generalized spike-wave discharges (GSWDs) in typical childhood absence epilepsy (CAE) and by implication their nosologic and taxonomic significance. Methods: Twenty-four abnormal video-electroencephalography (EEG) studies from 13 consecutive children with CAE and good response to appropriate antiepileptic drugs (AEDs) were analyzed. We studied the association between the topography of absence onset and the ictal automatisms, and the topographic correlation between FSWDs and GSWDs and their respective behavior during hyperventilation and the different states of phasic and nonphasic non-rapid eye movement (NREM) sleep. GSWDs were considered as of ''focal'' onset if a lead-in could be visibly recognized at a paper speed of 60 mm/s, and were classified by their topography. Key Findings: (1) Multifocal absences occurred in 10 children; anterior onset was noted in 81 absences (73.6%) from 12 children and posterior in 18 (16.4%) from 7 children; there was no association between topography of absence onset and ictal automatisms; (2) FSWDs occurred in 85% of children and were multifocal in 73% of them; 85% of FSWDs were anterior and 14% posterior; (3) there was good topographic association between FSWDs and the leading spike of GSWDs of ''focal'' onset in all children with FSWDs; (4) both FSWDs and GSWDs increased during hyperventilation; (5) FSWDs occurred mainly during noncyclical NREM sleep and during periods of reduced vigilance of cyclical NREM sleep, whereas GSWDs occurred during the periods of enhanced vigilance of NREM sleep; GSWDs occurred significantly more frequently than FSWDs at the transition from reduced to enhanced vigilance of NREM sleep. Significance: Our findings suggest that in CAE focal EEG paroxysms reflect a system of multifocal nonlocalizing electrically unstable cortical areas that under the facilitatory influence of exogenous or endogenous factors like sleep instability can foster a corticothalamic response of sufficient strength to generate 3-Hz GSWDs that are conditionally sustainable and potentially ictal. FSWDs can be viewed as incomplete forms of the GSWDs; together they define the EEG identity of idiopathic ''generalized'' epileptogenesis.

Study objectives: Sleep problems are associated with reduced physical and mental health. Altered function of the hypothalamic-pituitary-adrenocortical axis (HPAA) may be one underlying mechanism. We studied the associations between sleep problems and HPAA activity in children. Design: A cross-sectional epidemiological cohort study. Setting: Salivary cortisol was sampled throughout one day at home and during the Trier Social Stress Test for Children (TSST-C) in clinic. Sleep disorders were measured with a parent-rated Sleep Disturbance Scale for Children, and sleep duration measured by actigraphy for one week. Participants: 284 (51% girls) 8-year-old children. Results: Boys with sleep problems (!85th percentile in any of the sleep-wake transition, arousal, excessive daytime somnolence or sleep hyperhydrosis subscales) had lower diurnal salivary §

the (equally unknown) function of REM sleep. .. should be uncoupled from one another" (sect. 9, para. 4). In both the Introduction and in section 4 solms states that "not all dreaming is correlated with REM sleep." This may be the starting point to confront his model with nielsen's. Nielsen recognizes the difficulty of establishing a rigid correlation between REM/NREM sleep on one hand and different types of mentation on the other hand (the two generator isomorphic model). His proposed solution is straightforward: Whenever we encounter mentation during sleep, REM sleep processes, manifest or covert, must be at work. It is therefore a one-generator model, which identifies in REM sleep processes the unique source of mental activity during sleep. In my view, the model implicitly assumes that covert REM sleep processes are responsible for some form of brain activation, a feature that is hence shared by the two models. In fact, by disturbing the homeostatic condition of SWS, all physiological variables that connote the covert REM sleep processes may contribute to shifting the level of brain activation; nielsen specifically mentions cortical EEG desynchronisation in the "atypical NREM sleep episodes" (sect. 3.3) that may depend on covert REM sleep processes. Moreover, in the list of factors that might induce "convert REM sleep to be activated during NREM sleep" (sect. 3.2) quite a few (arousal processes, sensory stimulation, drug effects, sleep deprivation) are known to enhance the energy metabolism of the brain. The two facets of brain activation (electroencephalographic and metabolic) are therefore prerequisites for the model. nielsen's hypothesis is based on well known physiological evidence, and has the merit of being experimentally testable. Polygraphic recordings show that the transition from NREM to REM sleep is not a clearcut, abrupt event. Rather, different physiological variables change with different, contradictory time courses, and the macroscopic result may be the REM episode or an awakening or a return into NREM sleep. A single physiological variable can change alone, and may anticipate by many seconds, even minutes, the state change. It can be assumed that the complex process ultimately generating the full-blown REM sleep episode may have false starts and aborted outcomes; in this troubled transition (dynamic stage of train stem release in Parmeggiani's model, 1968); many physiological variables (increments in brain temperature and cerebral blood flow, heart rate, and blood pressure, Franzini 2000; motorneuron excitability changes, Nakamura et al. 1978) show a loose temporal link with the REM episode. All this can be translated, in the terminology of nielsen's model, as "covert REM sleep processes" (sect. 3.2). As nielsen acknowledges, "evidence of mentation in stage 3 and 4 sleep (Cavallero et al. 1992) is particularly difficult for this model to explain" (sect. 3.14, para. 4). The difficult task of validating the model requires: (1) that some of the physiological markers of "covert REM sleep processes" be identified in the uniform and stable conditions of stage 3 and 4 sleep; and (b) that the apparently "deactivated brain" of SWS may show focal signs of metabolic brain activation linked to the same physiological markers.

Polysomnography (PSG) is considered the gold standard for diagnosis of non-rapid eye movement (NREM) parasomnias, however its diagnostic yield has been rarely reported. We aimed to assess the diagnostic value of polysomnography in different categories of patients with suspected NREM parasomnia and define variables that can affect the outcome. 124 adults referred for polysomnography for suspected NREM parasomnia were retrospectively identified and divided into clinical categories based on their history. Each polysomnography was analysed for features of NREM parasomnia or different sleep disorders and for presence of potential precipitants. The impact on the outcome of number of recording nights and concomitant consumption of benzodiazepines and antidepressants was assessed. Overall, PSG confirmed NREM parasomnias in 60.5 % patients and showed a different sleep disorder in another 16 %. Precipitants were found in 21 % of the 124 patients. However, PSG showed limited value when the NREM parasomnia was clinically uncomplicated, since it rarely revealed a different diagnosis or unsuspected precipitants (5 % respectively), but became essential for people with unusual features in the history where different or overlapping diagnoses (18 %) or unsuspected precipitants (24 %) were commonly identified. Taking benzodiazepines or antidepressants during the PSG reduced the diagnostic yield. PSG has a high diagnostic yield in patients with suspected NREM parasomnia, and can reveal a different diagnosis or precipitants in over 40 % of people with complicated or atypical presentation or those with a history of epilepsy. We suggest that PSG should be performed for one night in the first instance, with leg electrodes and respiratory measurements and after benzodiazepine and antidepressant withdrawal.

Relations between common nightmares and chronobiological factors remain poorly understood. The possibility that nightmare frequency and distress are associated with chronotype (“morningness-eveningness”) was investigated in a sample of respondents to an Internet questionnaire. Over a 4½-year period, a total of 3978 subjects (mean age = 26.5 ± 11.6 yrs; age range = 10-69; 2933 female, 1045 male) submitted responses to single items about chronotype and nightmares as well as to other demographic variables. Analyses of chronotype and nightmares items by age and gender replicated most previous findings
for these measures—validating their further assessment—and uncovered abrupt increases in nightmare distress between ages 10-19 and 20-29 for females and ages 30-39 and 40-49 for males. Most important, there was a strong association
between nightmares and eveningness for female subjects. The latter was expressed as a linear association between nightmare frequency and increasing eveningness and a cubic association between nightmare distress and increasing eveningness; the definite evening types displayed the most severe nightmares.
The effect for nightmare frequency was independent of age and sleep duration but was eliminated when nightmare distress was covaried. For females, the nightmare/eveningness association appeared at ages 20 to 29 for the definite evening type and only later, at ages 30 to 39, for the moderate evening type. Findings are consistent with the possibility that nightmares are the expression of a more general pathological factor that is characteristic of eveningness and that is responsible for affective symptoms such as neuroticism and depression. This pathological factor appears to be expressed in late adolescence/
early adulthood, and relative morningness may be a protective factor delaying its onset. The well-established circadian modulations of cognitive, social, and affective tasks that are influenced by chronotype may extend to the memory and affective processes of sleep—including dreaming. This chronotypic influence, together with a likely gender difference in the neurophysiological substrate of emotional processing, may result in the differential occurrence of nightmares for female evening types.

study objectives: Determine the prevalence and gender distributions of behaviors enacted during dreaming ("dream-enacting [DE] behaviors") in a normal population; the independence of such behaviors from other parasomnias; and the influence of different question wordings, socially desirable responding and personality on prevalence. Design: 3-group questionnaire study setting: University classrooms Participants: Three undergraduate samples (Ns = 443, 201, 496; mean ages = 19.9 ± 3.2 y; 20.1 ± 3.4 y; 19.1 ± 1.6 y) interventions: N/A measurements and results: Subjects completed questionnaires about DE behaviors and Social Desirability. Study 1 employed a nonspecific question about the behaviors, Study 2 employed the same question with examples, and Study 3 employed 7 questions describing specific behavior subtypes (speaking, crying, smiling/laughing, fear, anger, movement, sexual arousal). Somnambulism, somniloquy, nightmares, dream recall, alexithymia, and absorption were also assessed. Factor analyses were conducted to determine relationships among DE behaviors and their independence from other parasomnias. Prevalence increased with increasing question specificity (35.9%, 76.7%, and 98.2% for the 3 samples). No gender difference obtained for the nonspecific question, but robust differences occurred for more specific questions. Females reported more speaking, crying, fear and smiling/laughing than did males; males reported more sexual arousal. When controlling other parasomnias and dream recall frequency, these differences persisted. Factor solutions revealed that DE behaviors were independent of other parasomnias and of dream recall frequency, except for an association between dreamtalking and somniloquy. Sexual arousal was related only to age. Behaviors were independent of alexithymia but moderately related to absorption. conclusions: Dream-enacting behaviors are prevalent in healthy subjects and sensitive to question wording but not social desirability. Subtypes are related, differ with gender and occur independently of other parasomnias.