Mental Activity During Episodes of Sleepwalking, Night Terrors or Confusional Arousals: Differences Between Children and Adults

How COVID-19 Affected Sleep Talking Episodes, Sleep and Dreams?

BACKGROUND

The COVID-19 pandemic increased symptoms of stress and anxiety and induced changes in sleep quality, dream activity, and parasomnia episodes. It has been shown that stressful factors and/or bad sleep habits can affect parasomnia behaviors. However, investigations on how COVID-19 has affected sleep, dreams, and episode frequency in parasomnias are rare. The current study focuses on the impact of the pandemic on a specific parasomnia characterized by speech production (sleep talking, ST).

METHODS

We selected 27 participants with frequent ST episodes (STs) during the pandemic and compared them with 27 participants with frequent STs from a previous study conducted during a pre-pandemic period. All participants performed home monitoring through sleep logs and recorded their nocturnal STs for one week.

RESULTS

We observed a higher frequency of STs in the pandemic group. Moreover, STs were related to the emotional intensity of dreams, independent of the pandemic condition. The pandemic was associated with lower bizarreness of dreams in the pandemic group. There were no differences in sleep variables between the two groups.

CONCLUSION

Overall, these results suggest a stressful effect of COVID-19 on the frequency of STs. Both the pandemic and the frequency of STs affect qualitative characteristics of dreams in this population.

Shared EEG correlates between non-REM parasomnia experiences and dreams

Sleepwalking and related parasomnias result from incomplete awakenings out of non-rapid eye movement sleep. Behavioral episodes can occur without consciousness or recollection, or in relation to dream-like experiences. To understand what accounts for these differences in consciousness and recall, here we recorded parasomnia episodes with high-density electroencephalography (EEG) and interviewed participants immediately afterward about their experiences. Compared to reports of no experience (19%), reports of conscious experience (56%) were preceded by high-amplitude EEG slow waves in anterior cortical regions and activation of posterior cortical regions, similar to previously described EEG correlates of dreaming. Recall of the content of the experience (56%), compared to no recall (25%), was associated with higher EEG activation in the right medial temporal region before movement onset. Our work suggests that the EEG correlates of parasomnia experiences are similar to those reported for dreams and may thus reflect core physiological processes involved in sleep consciousness.

The parasomnia defense in sleep-related homicide: A systematic review and a critical analysis of the medical literature

This review critically analyzes the forensic application of the Parasomnia Defense in homicidal incidents, drawing from medical literature on disorders of arousal (DOA) and rapid-eye-movement sleep behavior disorder (RBD). A systematic search of PubMed, Scopus, Embase, and Cochrane databases was conducted until October 16, 2022. We screened English-language articles in peer-reviewed journals discussing murders committed during sleep with a Parasomnia Defense. We followed PRISMA guidelines, extracting event details, diagnosis methods, factors influencing the acts, perpetrator behavior, timing, motives, concealment, mental experiences, victim demographics, and court verdicts. Three sleep experts evaluated each case. We selected ten homicides, four attempted homicides, and one homicide/attempted homicide that met inclusion/exclusion criteria. Most cases were suspected DOA as unanimously confirmed by experts. RBD cases were absent. Among aggressors, a minority reported dream-like experiences. Victims were primarily female family members killed in or near the bed by hands and/or with sharp objects. Objective sleep data and important crime scene details were often missing. Verdicts were ununiform. Homicides during DOA episodes, though rare, are documented, validating the Parasomnia Defense's use in forensics. RBD-related fatal aggression seems very uncommon. However, cases often lack diagnostic clarity. We propose updated guidelines to enhance future reporting and understanding of such incidents.

Somnambulism

Somnambulism, also called sleepwalking, classified as a non-rapid eye movement sleep parasomnia, encompasses a range of abnormal paroxysmal behaviors, leading to sleepwalking in dissociated sleep in an altered state of consciousness with impaired judgment and configuring a kind of hierarchical continuum with confusional arousal and night terror. Despite being generally regarded as a benign condition, its potential severity entails social, personal, and even forensic consequences. This comprehensive review provides an overview on the current state of knowledge, elucidating the phenomenon of somnambulism and encompassing its clinical manifestations and diagnostic approaches.

Challenges in diagnosing NREM parasomnias: Implications for future diagnostic classifications

NREM parasomnias are frequent and potentially disabling sleep disorders characterized by recurrent abnormal behaviors emerging from NREM sleep. Recently, several studies provided more detailed clinical and polysomnographic characterization of NREM parasomnia which may enhance the diagnostic process. Several revisions of the diagnostic criteria have been proposed in the classification of sleep disorders, the latest being ICSD-3-TR in 2023 with no changes on NREM parasomnias since ICSD-3 published in 2014. We performed an extensive literature review to assess the evidence on the procedure of its diagnosis. We dissected the inconsistencies and shortcomings in the ICSD-3-TR to propose a revision of the current diagnostic criteria. We highlighted the limits of several clinical criteria which should rather be supportive features than mandatory criteria. Infrared cameras with video-recordings with are promising tools to precisely characterize home episodes. Sensitive and specific polysomnographic markers of NREM parasomnias have been identified and should be considered in future revisions. We also suggest the use of diagnostic specifiers (clinical subtypes, clinical significance, levels of severity, age effect, levels of certainty) to define homogeneous subgroups of patients for therapeutic intervention and research purposes. In conclusion, we advocate for significant changes in the current diagnostic criteria of NREM parasomnias for future classification.

Nocturnal agitation: From sleep state dissociation to sleep-related dissociative state

Nocturnal agitation refers to a broad spectrum of symptoms from simple movements to aggressive behaviors with partial or complete loss of awareness. An accurate identification of its etiology is critical for appropriate therapeutic intervention. In children and young adults, distinguishing between non-rapid eye movement (NREM) sleep parasomnias and psychogenic non-parasomniac manifestations, a condition known as sleep-related dissociative disorder (SRDD), can be challenging. This review aims to summarize current clinical, neurophysiological, and epidemiological knowledge on NREM parasomnia and SRDD, and to present the pathophysiological hypotheses underlying these nocturnal manifestations. Sleepwalking, sleep terror and confusional arousals are the three main presentations of NREM parasomnias and share common clinical characteristics. Parasomniac episodes generally occur 30minutes to three hours after sleep-onset, they are usually short, lasting no more than few minutes and involve non-stereotyped, clumsy behaviors with frequent amnesia. The prevalence of NREM parasomnia decreases from 15-30% in children to 2-4% in adults. Parasomniac episodes are incomplete awakening from the deepest NREM sleep and are characterized by a dissociated brain activity, with a wake-like activation in motor and limbic structures and a preserved sleep in the fronto-parietal regions. SRDD is a less known condition characterized by dramatic, often very long episodes with frequent aggressive and potentially dangerous behaviors. SRDD episodes frequently occur in quiet wakefulness before falling asleep. These dissociative manifestations are frequently observed in the context of psychological trauma. The pathophysiology of SRDD is poorly understood but could involve transient changes in brain connectivity due to labile sleep-wake boundaries in predisposed individuals. We hypothesize that SRDD and NREM parasomnia are forms of sleep-related dissociative states favored by a sleep-wake state dissociation during sleep-onset and awakening process, respectively.

Home nocturnal infrared video to record non-rapid eye movement sleep parasomnias

To assess the feasibility, the acceptability and the usefulness of home nocturnal infrared video in recording the frequency and the complexity of non-rapid eye movement sleep parasomnias in adults, and in monitoring the treatment response. Twenty adult patients (10 males, median age 27.5 years) with a diagnosis of non-rapid eye movement parasomnia were consecutively enrolled. They had a face-to-face interview, completed self-reported questionnaires to assess clinical characteristics and performed a video-polysomnography in the Sleep Unit. Patients were then monitored at home during at least five consecutive nights using infrared-triggered cameras. They completed a sleep diary and questionnaires to evaluate the number of parasomniac episodes at home and the acceptability of the home nocturnal infrared video recording. Behavioural analyses were performed on home nocturnal infrared video and video-polysomnography recordings. Eight patients treated by clonazepam underwent a second home nocturnal infrared video recording during five consecutive days. All patients had at least one parasomniac episode during the home nocturnal infrared video monitoring, compared with 75% during the video-polysomnography. A minimum of three consecutive nights with home nocturnal infrared video was required to record at least one parasomniac episode. Most patients underestimated the frequency of episodes on the sleep diary compared with home nocturnal infrared video. Episodes recorded at home were often more complex than those recorded during the video-polysomnography. The user-perceived acceptability of the home nocturnal infrared video assessment was excellent. The frequency and the complexity of the parasomniac episodes decreased with clonazepam. Home nocturnal infrared video has good feasibility and acceptability, and may improve the evaluation of the phenotype and severity of the non-rapid eye movement parasomnias and of the treatment response in an ecological setting.

Diagnosis and Management of NREM Sleep Parasomnias in Children and Adults

Non-rapid eye movement (NREM) sleep parasomnias are recurrent abnormal behaviors emerging as incomplete arousals out of NREM sleep. Mounting evidence on NREM sleep parasomnias calls for an update of clinical and therapeutical strategies. In the current review, we summarize the state of the art and provide the necessary background to stimulate a critical revision of diagnostic criteria of disorders of arousal (DoA), the most common NREM sleep parasomnia. In particular, we highlight the poor sensitivity of the diagnostic items related to amnesia and absence of conscious experiences during DoA episodes, encourage the role of video-polysomnography and home-video recordings in the diagnostic and treatment work-up, and suggest three levels of diagnostic certainty based on clinical and objective findings. Furthermore, we highlight current gaps of knowledge that prevent the definition of standard guidelines and future research avenues.

Transdiagnostic cognitive behavioral therapy for nightmares and parasomnias

STUDY OBJECTIVES

This pilot study determined whether transdiagnostic cognitive behavioral therapy for parasomnias (CBTp) reduces parasomnia and activity levels during sleep in a sample of adult sleep clinic outpatients. A secondary objective was to assess whether treatment produces improvements in daytime fatigue/sleepiness, perceived cognition, mood, and depression/anxiety/stress, as well as functional impairment in work and leisure activities.

METHODS

This was a randomized controlled trial with CBTp and self-monitoring control conditions. Participants were 19 adults with a DSM 5 parasomnia disorder who received individual CBTp virtually from their homes. CBTp consisted of psychoeducation, sleep hygiene and safety instructions, relaxation training, parasomnia techniques, and relapse prevention in a 6-week manualized, structured program.

RESULTS

Using a repeated measures analysis of variance model, and relative to a self-monitoring control condition, results showed that CBTp produced statistically significant improvements in parasomnia frequency, severity, nocturnal activity, and sleep efficiency. There was a trend toward reduced sleep-onset latency and improved work and social adjustment. Of treated participants, 100% rated themselves as improved at study conclusion.

CONCLUSIONS

Implications of these findings are that cognitive behavioral interventions for parasomnias are effective in lessening parasomnias. More investigation into this type of treatment is warranted.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: Impact of Cognitive Behavioral Therapy on Parasomnias; URL: https://clinicaltrials.gov/ct2/show/NCT04633668; Identifier: NCT04633668.

CITATION

Vincent N, Dirkse D, Giannouli E, McQuarrie A. Transdiagnostic cognitive behavioral therapy for nightmares and parasomnias. J Clin Sleep Med. 2023;19(3):499-509.

Psychobiological personality traits of children and adolescents with disorders of arousal

INTRODUCTION

Disorders of arousal (DOA) are parasomnias that emerge from incomplete arousal out of Non-Rem Sleep (NREM) and lead to a broad variety of emotional and motor behaviours. Increasing evidence supports the hypothesis that specific psychopathological traits contribute to the multifactorial origin of these phenomena. The aim of the current multicenter study was to compare the personality profile of children and adolescents with and without DOA using the Junior Temperament and Character Inventory (JTCI).

METHODS

We enrolled 36 patients with a diagnosis of DOA (mean age of 11 ± 3 years, 64% males), and 36 healthy age and gender matched control subjects (mean age of 11.2 ± 3.6, years, 67% males). Their parents completed the Paris Arousal Disorder Severity Scale (PADSS), the Sleep Disturbance Scale for Children (SDSC) and the JTCI.

RESULTS

Patients with DOA reached significantly higher levels compared to their control group in total PADSS (p < 0.0001) and in total SDSC (p < 0.0001). They also displayed higher scores in novelty seeking (p = 0.005), harm avoidance (p = 0.01), self-transcendence (p = 0.006) JTCI subscales, and lower scores on the self-directedness subscale (p = 0.004).

CONCLUSION

Our pediatric sample with DOA exhibited specific psychobiological personality traits compared to age and gender matched subjects without DOA. These results shed light on new possible etiopathogenetic mechanisms, as TCI traits have been linked to specific genetic variants and brain circuits, like the reward system. Prospective studies are required to assess the effect of targeted psychological/psychiatric treatment on DOA symptomatology.

Violent and Complex Behaviors and Non-Restorative Sleep Are the Main Features of Disorders of Arousal in Adulthood: Real Picture or a More Severe Phenotype?

Disorders of arousal (DoA) are NREM parasomnias characterized by motor and emotional behaviors emerging from incomplete arousals from deep sleep. DoA are largely present in pediatric populations, a period during which they are labeled as self-limited manifestations. However, an extensive literature has shown that DoA can persist in adulthood, with different characteristics from childhood DoA. Adult DoA patients usually report excessive daily sleepiness, sleep-related violence during DoA episodes or potentially harmful behaviors, which are rare in childhood. The semeiological features of DoA episodes in adulthood may complicate differential diagnoses with other motor manifestations during sleep, in particular sleep-related hypermotor epilepsy. However, it cannot be excluded that adults with DoA attending sleep centers constitute a more severe phenotype, thus not being representative of adult DoA in the general population. Video-polysomnographic studies of DoA document a spectrum of motor patterns of different complexities, the simplest of which may often go unnoticed. Despite the different complexities of the episodes, neurophysiologic studies showed the co-existence of deep sleep and wakefulness during DoA episodes or even before their onset. These aspects make DoA an ideal model to investigate the mechanisms regulating local sleep, sleep arousal and cognitive functions including spatial and temporal orientation, attention or memory.

The Influence of Sleep Talking on Nocturnal Sleep and Sleep-Dependent Cognitive Processes

BACKGROUND

Sleep talking (ST) is characterized by the production of unaware verbal vocal activations (VBs) during sleep. ST seems potentially linked to linguistic and memory consolidation processes. However, sleep and dream characteristics and the relationship between verbal vocalizations (VBs) and cognitive functions are still unknown. Our study aimed to investigate qualitative sleep and dream features in sleep talkers (STs) compared to healthy subjects (CNTs) through retrospective and longitudinal measures and explore the relationship between ST and memory consolidation.

METHODS

We recruited N = 29 STs and N = 30 CNTs (age range of 18-35). Participants recorded their dreams and filled out sleep logs for seven consecutive days. Vocal activations of STs were audio-recorded. On the eighth day, we administered a word-pair task.

RESULTS

We showed that STs had significantly worse self-reported sleep quality. VBs were positively correlated with sleep fragmentation and negatively associated with the oneiric emotional load. No difference between groups was found in the memory consolidation rate.

CONCLUSIONS

Although ST is a benign phenomenon, we revealed that ST is associated with more sleep alterations and lower emotional intensity of dreams. In this vein, we support that ST depends on sleep fragmentation and could represent a potential window into sleep-dependent cognitive processes.

NREM Sleep Parasomnias Commencing in Childhood: Trauma and Atopy as Perpetuating Factors

Objective/Background: Phenotyping of non-rapid-eye-movement (NREM) parasomnias is currently poorly undertaken. This study aimed to determine whether there are differences phenotypically among childhood-, adolescent-, and adult-onset NREM parasomnias continuing into and presenting in adulthood. Patients/Methods: A retrospective, cohort study of patients presenting with NREM parasomnia between 2008 and 2019 (n = 307) was conducted. Disorders included sleepwalking (n = 231), night terrors (n = 150), sexualised behaviour in sleep (n = 50), and sleep-related eating disorder (n = 28). Results: Compared to the adult-onset NREM behaviours group, the childhood- and adolescent-onset groups were more likely to have a family history of NREM behaviours (p < 0.001), experience a greater spectrum of NREM disorders (p = 0.001), and report a history of sleep-talking significantly more frequently (p = 0.014). Atopy was most prevalent in the childhood-onset group (p = 0.001). Those with childhood-onset NREM parasomnias were significantly more likely to arouse from N3 sleep on video polysomnography (p = 0.0003). Psychiatric disorders were more likely to be comorbid in the adult-onset group (p = 0.012). A history of trauma coinciding with onset of NREM behaviours was significantly more common in the childhood- and adolescent-onset groups (p < 0.001). Conclusions: Significant differences exist across childhood-, adolescent-, and adult-onset NREM parasomnia presenting in adulthood. This study suggests that adult-onset slow-wave sleep disorders may be confounded by psychiatric disorders resulting in nocturnal sleep disruption and that unresolved traumatic life experiences perpetuate NREM disorders arising in childhood and comprise one of the strongest external risk factors for triggering and perpetuating these disorders in adolescence.

Sleepwalking, sleep terrors, sexsomnia and other disorders of arousal: the old and the new

Disorders of arousal (DOA) is an umbrella term initially covering classical sleepwalking, sleep terrors, and confusional arousals, and now including a wider spectrum of specialised forms of non rapid eye movement (non REM) parasomnias such as sexsomnia, sleep-related eating disorder, and sleep-related choking syndrome. Growing evidence has shown that DOA are not restricted to children but are also prevalent in adults (2%-4% of the adult population). While DOA run in family, genetics studies remain scarce and inconclusive. In addition to the risk of injury on themselves and others (including sexual assaults in sexsomnia), adults with DOA frequently suffer from excessive daytime sleepiness, pain, and altered quality of life. The widespread view of DOA as automatic and amnesiac behaviours has now been challenged by subjective (dream reports) and objective (dream-enacting behaviours documented on video-polysomnography) observations, suggesting that sleepwalkers are 'dream walking' during their episodes. Behavioural, experiential, cognitive, and brain (scalp electroencephalography [EEG], stereo-EEG, high density-EEG, functional brain imaging) data converge in showing a dissociated pattern during the episodes. This dissociated pattern resembles the new concept of local arousal with a wake-like activation in motor and limbic regions and a preserved (or even increased) sleep intensity over a frontoparietal network. EEG and behavioural criteria supporting the DOA diagnosis with high sensitivity and specificity are now available. However, treatment is still based on controlling priming and precipitating factors, as well as on clinicians' personal experience with sedative drugs. Placebo-controlled trials are needed to improve patients' treatment. DOA deserve more attention from sleep researchers and clinicians.

EEG Activation Does Not Differ in Simple and Complex Episodes of Disorders of Arousal: A Spectral Analysis Study

PURPOSE

Disorders of arousal (DoA) are characterized by incomplete awakening from NREM sleep, with the admixture of both deep sleep and wake EEG activity. Previous observations suggested that changes in EEG activity could be detected in the seconds preceding DoA episodes. The aims of this work were to characterize the topography of EEG spectral changes prior to DoA episodes and to investigate whether or not behavioral complexity could be predicted by changes in EEG immediately preceding behavioral onsets.

PATIENTS AND METHODS

We collected 103 consecutive video-polysomnographic recordings of 53 DoA adult patients and classified all episodes as simple, rising and complex arousal movements. For each episode, a 5-second window preceding its motor onset ("pre-event") and a 60-second window from 2 to 3 minutes before the episodes ("baseline") were compared. Subsequently, a between-group comparison was performed for the pre-event of simpler versus the more complex episodes.

RESULTS

Spectral analysis over 325 DoA episodes showed an absolute significant increase prior to DoA episodes in all frequency bands excluding sigma, which displayed the opposite effect. In normalized maps, the increase was relatively higher over the central/anterior areas for both slow and fast frequency bands. No significant differences emerged from the comparison between simpler and more complex episodes.

CONCLUSION

Taken together, these results show that deep sleep and wake-like EEG rhythms coexist over overlapping areas before DoA episodes, suggesting an alteration of local sleep mechanisms. Episodes of different complexity are preceded by a similar EEG activation, implying that they possibly share a similar pathophysiology.