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.

Evaluation of hypersomnolence: From symptoms to diagnosis, a multidimensional approach.

Hypersomnolence is a major public health issue given its high frequency, its impact on academic/occupational functioning and on accidentology, as well as its heavy socio-economic burden. The positive and aetiological diagnosis is crucial, as it determines the therapeutic strategy. It must consider the following aspects: i) hypersomnolence is a complex concept referring to symptoms as varied as excessive daytime sleepiness, excessive need for sleep, sleep inertia, or drowsiness, all of which warrant specific dedicated investigations; ii) the boundary between physiological and abnormal hypersomnolence is blurred, since most symptoms can be encountered in the general population to varying degrees without being considered as pathological, meaning that their severity, frequency, context of occurrence and related impairment need to be carefully assessed; iii) investigation of hypersomnolence relies on scales/questionnaires as well as behavioural and neurophysiological tests, which measure one or more dimensions, keeping in mind the possible discrepancy between objective and subjective assessment; iv) aetiological reasoning is driven by knowledge of the main sleep regulation mechanisms, epidemiology, and associated symptoms. The need to assess hypersomnolence is growing, both for its management, and for assessing the efficacy of treatments. The landscape of tools available for investigating hypersomnolence is constantly evolving, in parallel with research into sleep physiology and technical advances. These investigations face the challenges of reconciling subjective perception and objective data, making tools accessible to as many people as possible and predicting the risk of accidents.

[Introduction to the hierarchical taxonomy of psychopathology]. / Introduction à la taxonomie hiérarchique de la psychopathologie.

INTRODUCTION: In clinical practice, the usefulness of diagnosis based on the Diagnostic or Statistical Manual of Mental Disorders (DSM) or the International Classification of Diseases, 11th edition, appears essential from a clinical, research, epidemiological, administrative, economic and political level. However, such diagnostic systems have shortcomings in terms of validity, little consideration of comorbidities and strong intra-class heterogeneity. On a structural level, the operationalization of its criteria is based on a reliability which has been defined a posteriori and which does not lead to improving the validity of the diagnosis but rather to the reification of the diagnostic categories. METHODS: First published in its current form in 2017, the Hierarchical Taxonomy of Psychopathology (HiTOP) constitutes a nosological alternative based on statistics. It conceptualizes psychopathology as a set of hierarchical dimensions, i.e. in "transdiagnostic" continua. The HiTOP is structured according to super-spectra, spectra, sub-factors, syndromes, components and symptoms. This comes from the current dimensional psychology and quantitative nosology. This article describes the basic principles of the HiTOP project and its potential to integrate into clinical and psychiatric research based on its advantages and limitations. RESULTS: Unlike the DSM, which is descriptive and categorical, the HiTOP is first a dimensional classification. This dimensionality describes psychiatric phenomena on continua, each dimension providing a diagnostic continuum to situate a clinical patient. This dimensionality avoids the reification of categories and it limits the dichotomy between normal and pathological. In addition, HiTOP shows a hierarchical structure: vertical refinement of dimensions allows to circumvent the problem of comorbidities, proposes a new conception of etiopathogenic mechanisms, and improves management of care. DISCUSSION: Thus, we provide an illustration of the applications of a dimensional and hierarchical classification in current clinical practice and scientific research, compared to traditional nosology. The challenges of the HiTOP arise in terms of validity, i.e. in the relation of dimensions with physiopathological mechanisms, in clinical terms, i.e. in the potential contribution of dimensions in relation to categories. Moreover, methodological challenges will be important given the inherent limitations of the HiTOP. CONCLUSION: The HiTOP allows to examine the conceptualization of psychiatric disorders, the search for explanatory mechanisms, and treatment from another perspective for psychiatry.

EEG Neurofeedback for Anxiety Disorders and Post-Traumatic Stress Disorders: A Blueprint for a Promising Brain-Based Therapy.

PURPOSE OF REVIEW: This review provides an overview of current knowledge and understanding of EEG neurofeedback for anxiety disorders and post-traumatic stress disorders. RECENT FINDINGS: The manifestations of anxiety disorders and post-traumatic stress disorders (PTSD) are associated with dysfunctions of neurophysiological stress axes and brain arousal circuits, which are important dimensions of the research domain criteria (RDoC). Even if the pathophysiology of these disorders is complex, one of its defining signatures is behavioral and physiological over-arousal. Interestingly, arousal-related brain activity can be modulated by electroencephalogram-based neurofeedback (EEG NF), a non-pharmacological and non-invasive method that involves neurocognitive training through a brain-computer interface (BCI). EEG NF is characterized by a simultaneous learning process where both patient and computer are involved in modifying neuronal activity or connectivity, thereby improving associated symptoms of anxiety and/or over-arousal. Positive effects of EEG NF have been described for both anxiety disorders and PTSD, yet due to a number of methodological issues, it remains unclear whether symptom improvement is the direct result of neurophysiological changes targeted by EEG NF. Thus, in this work we sought to bridge current knowledge on brain mechanisms of arousal with past and present EEG NF therapies for anxiety and PTSD. In a nutshell, we discuss the neurophysiological mechanisms underlying the effects of EEG NF in anxiety disorder and PTSD, the methodological strengths/weaknesses of existing EEG NF randomized controlled trials for these disorders, and the neuropsychological factors that may impact NF training success.

[Network analysis by systemic text excavation of the concept of personalized psychiatry and precision]. / Analyse en réseau par fouille de données textuelles systématique du concept de psychiatrie personnalisée et de précision.

OBJECTIVES: The current challenges of psychiatric nosology and semiology are part of an interdisciplinary and integrative framework. The paradigm of the personalized and precision psychiatry proposes to study this discipline according to new approaches and methodologies. Personalized and precision psychiatry therefore requires clarification of its concepts. To our knowledge, there is no systematic exploration of the literature on the application of the concepts of personalized and precision medicine in the field of psychiatry. This article proposes thus to explore the framework of personalized and precision medicine applied to psychiatry. METHODS: We explored the framework of personalized and precision medicine applied to psychiatry by a textual network analysis. Firstly, we performed a systematic text-mining (Natural Language Processing) from an exhaustive review of the international literature with the terms "precision psychiatry" and "personalized psychiatry". Secondly, this analysis of textual data allowed us to build a textual network which made it possible to visualize the most proximal terms (the most frequently associated in the literature). Finally, we extracted from the network the main dimensions explored in the scientific literature, and we studied the relative importance of each term by analyzing the network centrality. In addition, a brief bibliometric analysis was conducted. RESULTS: We show that personalized and precision psychiatry refers to six dimensions found in the textual network analysis which correspond to the scientific fields which study personalized and precision psychiatry: genetics, pharmacogenetics, artificial intelligence, therapeutic trials, biomarkers and staging. We explore how each dimension relates to the mechanization of psychiatric disorders. However, precision and personalized psychiatry, which tries to refine the levels of mechanistic explanations for psychiatry, suffers from a conceptual heterogeneity. Indeed, textual analysis also allows us to find terms referring to a set of heterogeneous concepts. Many methodological fields and epistemological concepts are invoked in this literature, without standardization. CONCLUSIONS: The paradox of personalized and precision psychiatry is to associate a strong conceptual heterogeneity with a well-defined mechanistic component. Heterogeneity found in literature on personalized and precision psychiatry testifies to the lack of a pluralist and integrative theoretical framework. This framework could be based on a naturalizing but non-reducing formalism, aware of the societal challenges of the sciences and their implementation in the research and clinical systems of psychiatry.

Practical considerations for the evaluation and management of Attention Deficit Hyperactivity Disorder (ADHD) in adults.

Attention deficit with or without hyperactivity disorder (ADHD) is one of the most frequent neuropsychiatric disorders, and affects 2-4% of adults. In contrast with many European countries, the identification and management of adult ADHD remains underdeveloped in France, and a subject of controversy. This review provides a practical update on current knowledge about ADHD in adults for French-speaking professionals who have to detect or manage adult patients with ADHD. ADHD is classified as a neurodevelopmental disorder in the recent update of the international diagnostic classification. While symptoms and impairment due to ADHD are frequently severe during childhood, they often evolve as children grow older, with frequent persistent disabilities in adulthood. In adulthood, the clinical presentation, as in childhood, involves the symptom triad of inattention, hyperactivity and impulsivity. However, differences are noted: hyperactivity is more often internalized, symptoms of inattention may be masked by anxiety symptoms or obsessive-like compensation strategies. ADHD is often diagnosed during childhood, but it is not rare for the diagnosis to be made later. Failure to recognise symptoms resulting in misdiagnosis, or alternatively well-developed compensation factors could be two underlying reasons for the long delay until diagnosis. Other symptoms, such as emotional deregulation or executive function-related symptoms are also usually observed in adults. In addition, in adults, ADHD is often associated with other psychiatric disorders (in 80% of cases); this makes the diagnosis even more difficult. These disorders encompass a broad spectrum, from mood disorders (unipolar or bipolar), to anxiety disorders, and other neurodevelopmental disorders and personality disorders, especially borderline and antisocial personality disorder. Substance-use disorders are very common, either as a consequence of impulsivity and emotional dysregulation or as an attempt at self-treatment. Sleep disorders, especially restless leg syndrome and hypersomnolence, could share common pathophysiological mechanisms with ADHD. ADHD and comorbidity-related symptoms are responsible for serious functional impairment, in various domains, leading to academic, social, vocational, and familial consequences. The impact on other psychiatric disorders as an aggravating factor should also be considered. The considerable disability and the poorer quality of life among adults with ADHD warrant optimal evaluation and management. The diagnostic procedure for ADHD among adults should be systematic. Once the positive diagnosis is made, the evaluation enables characterisation of the levels of severity and impairment at individual level. A full examination should also assess medical conditions associated with ADHD, to provide personalized care. In recent years, a growing number of assessment tools have been translated and validated in French providing a wide range of structured interviews and standardized self-report questionnaires for the evaluation of core and associated ADHD symptoms, comorbidities and functional impairment. The treatment of ADHD in adults is multimodal, and aims to relieve the symptoms, limit the burden of the disease, and manage comorbidities. The most relevant and validated psychological approaches are psycho-education, cognitive-behavioural therapy and "third wave therapies" with a specific focus on emotional regulation. Cognitive remediation and neurofeedback are promising strategies still under evaluation. Medications, especially psychostimulants, are effective for alleviating ADHD symptoms with a large effect size. Their safety and tolerance are satisfactory, although their long-term clinical benefit is still under discussion. In France, methylphenidate is the only stimulant available for the treatment of ADHD. Unfortunately, there is no authorization for its use among adults except in continuation after adolescence. Hence the prescription, which is subject to the regulations on narcotics, is off-label in France. This article aims to provide practical considerations for the management of ADHD and associated disorders in adults, in this particular French context.

The use of melatonin in adult psychiatric disorders: Expert recommendations by the French institute of medical research on sleep (SFRMS).

Melatonin is a hormone secreted by the pineal gland at night. This hormone has many physiological functions, the main one being to synchronise individuals' biological rhythms. Exogenous melatonin has the same chronobiotic action, even at small doses (0.125mg). In addition, a sleep-inducing (soporific) action appears to occur in a dose-effect relationship, i.e. as the dose increases. In psychiatric disorders, these two effects could have interesting applications in clinical practice. The French institute of medical research on sleep (SFRMS) appointed a group of experts to conduct a consensus conference to study the indications of melatonin and the conditions of its prescription. An account of the conclusions on adult psychiatric disorders (presented orally at the Congress on Sleep in Marseille, 23 November 2017) is given here. Exogenous melatonin proves to be useful among patients with a stabilized psychiatric disorder or in remission, to prevent relapse in case of associated complaints of insomnia, poor quality sleep or delayed sleep phase syndrome. During acute phases, melatonin could be used as an adjuvant treatment when there are insomnia symptoms, in mood disorders (bipolar disorder, major depressive disorder, seasonal affective disorder), in attention deficit hyperactivity disorder (ADHD), in peri-surgical anxiety and in schizophrenia. In somatoform disorders, melatonin is a possible treatment for painful symptoms in fibromyalgia, irritable bowel syndrome, functional dyspeptic syndrome and temporomandibular joint dysfunction.

EEG neurofeedback research: A fertile ground for psychiatry?

The clinical efficacy of neurofeedback is still a matter of debate. This paper analyzes the factors that should be taken into account in a transdisciplinary approach to evaluate the use of EEG NFB as a therapeutic tool in psychiatry. Neurofeedback is a neurocognitive therapy based on human-computer interaction that enables subjects to train voluntarily and modify functional biomarkers that are related to a defined mental disorder. We investigate three kinds of factors related to this definition of neurofeedback. We focus this article on EEG NFB. The first part of the paper investigates neurophysiological factors underlying the brain mechanisms driving NFB training and learning to modify a functional biomarker voluntarily. Two kinds of neuroplasticity involved in neurofeedback are analyzed: Hebbian neuroplasticity, i.e. long-term modification of neural membrane excitability and/or synaptic potentiation, and homeostatic neuroplasticity, i.e. homeostasis attempts to stabilize network activity. The second part investigates psychophysiological factors related to the targeted biomarker. It is demonstrated that neurofeedback involves clearly defining which kind of relationship between EEG biomarkers and clinical dimensions (symptoms or cognitive processes) is to be targeted. A nomenclature of accurate EEG biomarkers is proposed in the form of a short EEG encyclopedia (EEGcopia). The third part investigates human-computer interaction factors for optimizing NFB training and learning during the closed loop interaction. A model is proposed to summarize the different features that should be controlled to optimize learning. The need for accurate and reliable metrics of training and learning in line with human-computer interaction is also emphasized, including targeted biomarkers and neuroplasticity. All these factors related to neurofeedback show that it can be considered as a fertile ground for innovative research in psychiatry.

Making psychiatric semiology great again: A semiologic, not nosologic challenge.

This article analyzes whether psychiatric disorders can be considered different from non-psychiatric disorders on a nosologic or semiologic point of view. The supposed difference between psychiatric and non-psychiatric disorders relates to the fact that the individuation of psychiatric disorders seems more complex than for non-psychiatric disorders. This individuation process can be related to nosologic and semiologic considerations. The first part of the article analyzes whether the ways of constructing classifications of psychiatric disorders are different than for non-psychiatric disorders. The ways of establishing the boundaries between the normal and the pathologic, and of classifying the signs and symptoms in different categories of disorder, are analyzed. Rather than highlighting the specificity of psychiatric disorders, nosologic investigation reveals conceptual notions that apply to the entire field of medicine when we seek to establish the boundaries between the normal and the pathologic and between different disorders. Psychiatry is thus very important in medicine because it exemplifies the inherent problem of the construction of cognitive schemes imposed on clinical and scientific medical information to delineate a classification of disorders and increase its comprehensibility and utility. The second part of this article assesses whether the clinical manifestations of psychiatric disorders (semiology) are specific to the point that they are entities that are different from non-psychiatric disorders. The attribution of clinical manifestations in the different classifications (Research Diagnostic Criteria, Diagnostic Statistic Manual, Research Domain Criteria) is analyzed. Then the two principal models on signs and symptoms, i.e. the latent variable model and the causal network model, are assessed. Unlike nosologic investigation, semiologic analysis is able to reveal specific psychiatric features in a patient. The challenge, therefore, is to better define and classify signs and symptoms in psychiatry based on a dual and mutually interactive biological and psychological perspective, and to incorporate semiologic psychiatry into an integrative, multilevel and multisystem brain and cognitive approach.

[What do virtual reality tools bring to child and adolescent psychiatry?] / Qu'apportent les outils de réalité virtuelle en psychiatrie de l'enfant et l'adolescent ?

Virtual reality is a relatively new technology that enables individuals to immerse themselves in a virtual world. It offers several advantages including a more realistic, lifelike environment that may allow subjects to "forget" they are being assessed, allow a better participation and an increased generalization of learning. Moreover, the virtual reality system can provide multimodal stimuli, such as visual and auditory stimuli, and can also be used to evaluate the patient's multimodal integration and to aid rehabilitation of cognitive abilities. The use of virtual reality to treat various psychiatric disorders in adults (phobic anxiety disorders, post-traumatic stress disorder, eating disorders, addictions…) and its efficacy is supported by numerous studies. Similar research for children and adolescents is lagging behind. This may be particularly beneficial to children who often show great interest and considerable success on computer, console or videogame tasks. This article will expose the main studies that have used virtual reality with children and adolescents suffering from psychiatric disorders. The use of virtual reality to treat anxiety disorders in adults is gaining popularity and its efficacy is supported by various studies. Most of the studies attest to the significant efficacy of the virtual reality exposure therapy (or in virtuo exposure). In children, studies have covered arachnophobia social anxiety and school refusal phobia. Despite the limited number of studies, results are very encouraging for treatment in anxiety disorders. Several studies have reported the clinical use of virtual reality technology for children and adolescents with autistic spectrum disorders (ASD). Extensive research has proven the efficiency of technologies as support tools for therapy. Researches are found to be focused on communication and on learning and social imitation skills. Virtual reality is also well accepted by subjects with ASD. The virtual environment offers the opportunity to administer controlled tasks such as the typical neuropsychological tools, but in an environment much more like a standard classroom. The virtual reality classroom offers several advantages compared to classical tools such as more realistic and lifelike environment but also records various measures in standardized conditions. Most of the studies using a virtual classroom have found that children with Attention Deficit/Hyperactivity Disorder make significantly fewer correct hits and more commission errors compared with controls. The virtual classroom has proven to be a good clinical tool for evaluation of attention in ADHD. For eating disorders, cognitive behavioural therapy (CBT) program enhanced by a body image specific component using virtual reality techniques was shown to be more efficient than cognitive behavioural therapy alone. The body image-specific component using virtual reality techniques boots efficiency and accelerates the CBT change process for eating disorders. Virtual reality is a relatively new technology and its application in child and adolescent psychiatry is recent. However, this technique is still in its infancy and much work is needed including controlled trials before it can be introduced in routine clinical use. Virtual reality interventions should also investigate how newly acquired skills are transferred to the real world. At present virtual reality can be considered a useful tool in evaluation and treatment for child and adolescent disorders.