Sample records for somnambulism

  1. Lord Byron's physician: John William Polidori on somnambulism. (United States)

    Finger, Stanley; Stiles, Anne


    John William Polidori (1795-1821) was the Edinburgh-trained physician hired by Lord Byron to accompany him to Switzerland, where he participated in the story-telling event proposed by Byron that led, with Polidori's help, to Mary Shelley's Frankenstein. Although those interested in English literature might also remember Polidori as the author of The Vampyre, one of the first extended works of fiction about vampires, his earlier interest in somnambulism and trance states is only beginning to be appreciated. Even more than students of Romantic literature, historians of science and medicine seem little aware of what Polidori had written about oneirodynia, a synonym for somnambulism, and how his thoughts from 1815 about such activities reflected the changing medical zeitgeist at this time. This chapter examines Polidori's medical thesis in a neuroscience context and compares what he wrote to the writings of several other physicians who were fascinated by nocturnal wanderings, their causes, their manifestations, and their possible treatments. © 2013 Elsevier B.V. All rights reserved.

  2. Sleep and wakefulness in somnambulism: a spectral analysis study. (United States)

    Guilleminault, C; Poyares, D; Aftab, F A; Palombini, L; Abat, F


    The sleep structure and the dynamics of EEG slow-wave activity (SWA) were investigated in 12 young adults and age- and gender-matched controls. Polysomnography was performed in subjects with well-documented chronic sleepwalking and in matched controls. Blinded visual scoring was performed using the international criteria from the Rechtschaffen and Kales atlas [A manual of standardized technology, techniques and scoring systems for sleep stages of human subjects. Los Angeles: UCLA Brain Information Service, Brain Research Institute, 1968.] and by determining the presence of microarousals as defined in the American Sleep Disorders Association (ASDA) atlas [Sleep 15 (1992) 173.]. An evaluation of SWA overnight was performed on total nocturnal sleep to determine if a difference existed between groups of subjects, since sleepwalking usually originates with slow-wave sleep. Investigation of the delta power in successive nonoverlapping 4-second windows in the 32 seconds just prior to EMG activity associated with a confusional arousal was also conducted. One central EEG lead was used for all analyses. Somnambulistic individuals experienced more disturbed sleep than controls during the first NREM-REM sleep cycle. They had a higher number of ASDA arousals and presented lower peak of SWA during the first cycle that led to a lower SWA decline overnight. When the investigation focused on the short segment immediately preceding a confusional arousal, they presented an important increase in the relative power of low delta (0.75-2 Hz) just prior to the confusional arousal. Sleepwalkers undergo disturbed nocturnal sleep at the beginning of the night. The increased power of low delta just prior to the confusional arousal experienced may not be related to Stages 3-4 NREM sleep. We hypothesize that it may be translated as a cortical reaction to brain activation.

  3. Komplekse skader i forbindelse med søvngaengeri

    DEFF Research Database (Denmark)

    Sillesen, Nanna Hylleholt; Nielsen, Lisa Toft; Bonde, Christian


    Up to 3% of adults walk in their sleep and some perform complex behaviours. Treatment recommendations for sleepwalking are inconsistent. This case report describes a 64-year-old man who climbed out of a 2nd floor toilet window during somnambulism. He fell 6-8 meters and fractured the tibia, fibul......, cervical columna, lumbal columna, calcaneus, costae and suffered a pneumothorax. Evidence to support sleepwalking treatment is lacking and besides benzodiazepines, prevention is the preferred treatment choice according to the literature....

  4. Quetiapine-induced sleep-related eating disorder-like behavior: a case series

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    Tamanna Sadeka


    Full Text Available Abstract Introduction Somnambulism or sleepwalking is a disorder of arousal from non-rapid eye movement sleep. The prevalence of sleep-related eating disorder has been found to be approximately between 1% and 5% among adults. Many cases of medication-related somnambulism and sleep-related eating disorder-like behavior have been reported in the literature. Quetiapine, an atypical antipsychotic medication, has been associated with somnambulism but has not yet been reported to be associated with sleep-related eating disorder. Case presentation Case 1 is a 51-year-old obese African American male veteran with a body mass index of 34.11kg/m2 and severe sleep apnea who has taken 150mg of quetiapine at bedtime for more than one year for depression. He developed sleepwalking three to four nights per week which resolved after stopping quetiapine while being compliant with bi-level positive pressure ventilation therapy. At one year follow-up, his body mass index was 32.57kg/m2. Case 2 is a 50-year-old African American female veteran with a body mass index of 30.5kg/m2 and mild sleep apnea who has taken 200mg of quetiapine daily for more than one year for depression. She was witnessed to sleepwalk three nights per week which resolved after discontinuing quetiapine while being treated with continuous positive airway pressure. At three months follow-up, her body mass index was 29.1kg/m2. Conclusion These cases illustrate that quetiapine may precipitate complex motor behavior including sleep-related eating disorder and somnambulism in susceptible patients. Atypical antipsychotics are commonly used in psychiatric and primary care practice, which means the population at risk of developing parasomnia may often go unrecognized. It is important to recognize this potential adverse effect of quetiapine and, to prevent injury and worsening obesity, discuss this with the patients who are prescribed these medications.

  5. Nocturnal enuresis in a longitudinal perspective. A primary problem of maturity and/or a secondary environmental reaction? (United States)

    Klackenberg, G


    The study is part of a prospective longitudinal investigation, involving annual somatic, psychological and social check-ups in a random sample of 212 children. Data are presented on the gradual achievement of bladder control, with relapses into wetting. Information is provided on relationships with training, with behavioural variables, with emotional maturity (Rorschach) and with sleep. It seems probable that primary enuresis usually ceases by the age of 8 at the latest and that enuresis in older children is a secondary emotional disorder which may, however, have started at an earlier age. The 6-year-old enuretic shows signs of delayed emotional maturity. The relation with somnambulism is ambiguous. Enuresis is not significantly related to training. None of the data obtained in this study conflict with the theory that primary enuresis is chiefly a maturity problem, the nature of which can be emotional. The neurophysiological aspect has not been investigated.

  6. Preaching What We Practice: Teaching Ethical Decision-Making to Computer Security Professionals (United States)

    Fleischmann, Kenneth R.

    The biggest challenge facing computer security researchers and professionals is not learning how to make ethical decisions; rather it is learning how to recognize ethical decisions. All too often, technology development suffers from what Langdon Winner terms technological somnambulism - we sleepwalk through our technology design, following past precedents without a second thought, and fail to consider the perspectives of other stakeholders [1]. Computer security research and practice involves a number of opportunities for ethical decisions. For example, decisions about whether or not to automatically provide security updates involve tradeoffs related to caring versus user autonomy. Decisions about online voting include tradeoffs between convenience and security. Finally, decisions about routinely screening e-mails for spam involve tradeoffs of efficiency and privacy. It is critical that these and other decisions facing computer security researchers and professionals are confronted head on as value-laden design decisions, and that computer security researchers and professionals consider the perspectives of various stakeholders in making these decisions.

  7. Buenos Aires mesmérica. Hipnosis y magnetismo en la cultura y la ciencia de la capital argentina (1870-1900

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    Mauro Sebastián Vallejo


     Abstract The purpose of this paper is to analyze the topic of hypnotism in the science and the culture of Buenos Aires during the last quarter of the nineteenth century. When Argentine medicine became conceptually and practically interested in hypnosis it encoun­tered a multiplicity of actors (spirititsts, illusionists, quacks that also used it with different aims. This text intends to describe the tensions and disputes sustained between physi­cians and their competitors. In addition to pointing out which were the professionals that contributed to the study of the new therapy, this paper identifies the strategies carried out by representatives of the official science in order to finish with other uses of artificial somnambulism

  8. A comparison of complex sleep behaviors with two short-acting Z-hypnosedative drugs in nonpsychotic patients

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    Chen LF


    Full Text Available Li-Fen Chen,1 Ching-En Lin,1–3 Yu-Ching Chou,4 Wei-Chung Mao,1,5 Yi-Chyan Chen,1–3 Nian-Sheng Tzeng1,6 1Department of Psychiatry, Tri-Service General Hospital, School of Medicine, National Defense Medical Center, Taipei City, Taiwan; 2Taipei Tzu Chi Hospital, The Buddhist Medical Foundation, Taipei, Taiwan; 3School of Medicine, Tzu Chi University, Hualien, Taiwan; 4School of Public Health, National Defense Medical Center, Taipei City, Taiwan; 5Institute of Brain Science, School of Medicine, National Yang-Ming University, Taipei City, Taiwan; 6Student Counseling Center, National Defense Medical Center, Taipei City, Taiwan Objective: Complex sleep behaviors (CSBs are classified as “parasomnias” in the International Classification of Sleep Disorders, Second Edition (ICSD-2. To realize the potential danger after taking two short-acting Z-hypnosedative drugs, we estimated the incidence of CSBs in nonpsychotic patients in Taiwan. Methods: Subjects (N = 1,220 using zolpidem or zopiclone were enrolled from the psychiatric outpatient clinics of a medical center in Taiwan over a 16-month period in 2006–2007. Subjects with zolpidem (N = 1,132 and subjects with zopiclone (N = 88 were analyzed. All subjects completed a questionnaire that included demographic data and complex sleep behaviors after taking hypnotics. Results: Among zolpidem and zopiclone users, 3.28% of patients reported incidents of somnambulism or amnesic sleep-related behavior problems. The incidence of CSBs with zolpidem and zopiclone were 3.27%, and 3.41%, respectively, which was significantly lower than other studies in Taiwan. Conclusion: These results serve as a reminder for clinicians to make inquiries regarding any unusual performance of parasomnic activities when prescribing zolpidem or zopiclone. Keywords: parasomnia, somnambulism, amnesic sleep-related behavior, sleepwalking, zolpidem, zopiclone

  9. Relationships between non-pathological dream-enactment and mirror behaviors. (United States)

    Nielsen, Tore; Kuiken, Don


    Dream-enacting behaviors (DEBs) are behavioral expressions of forceful dream images often occurring during sleep-to-wakefulness transitions. We propose that DEBs reflect brain activity underlying social cognition, in particular, motor-affective resonance generated by the mirror neuron system. We developed a Mirror Behavior Questionnaire (MBQ) to assess some dimensions of mirror behaviors and investigated relationships between MBQ scores and DEBs in a large of university undergraduate cohort. MBQ scores were normally distributed and described by a four-factor structure (Empathy/Emotional Contagion, Behavioral Imitation, Sleepiness/Anger Contagion, Motor Skill Imitation). DEB scores correlated positively with MBQ total and factor scores even with social desirability, somnambulism and somniloquy controlled. Emotion-specific DEB items correlated with corresponding emotion-specific MBQ items, especially crying and smiling. Results provide preliminary evidence for cross-state relationships between propensities for dream-enacting and mirror behaviors--especially behaviors involving motor-affective resonance--and our suggestion that motor-affective resonance mediates dream-enactment imagery during sleep and emotional empathy during waking. Copyright © 2013 Elsevier Inc. All rights reserved.

  10. From catalepsy to psychical research: The itinerary of Timothée Puel (1812-1890). (United States)

    Evrard, Renaud; Pratte, Erika Annabelle


    The physician and botanist Timothée Puel (1812-1890) lived through a pivotal period of psychology (1848-1878), between the academic prohibition of the study of animal magnetism to its disjointed recovery in hypnotism and psychical research. One of his cases of "catalepsy complicated with somnambulism" triggered a lively debate on "extraordinary neuroses" within the young Société médico-psychologique [Medico-psychological Society]. In 1874, Puel founded the Revue de psychologie expérimentale [Journal of Experimental Psychology], the first of its kind in French, which he intended as the vehicle of international interest in psychical research, the scholarly and institutionalized study of "psychism" that prepared the way for the recognition of academic psychology. Puel circulated between these different currents by taking advantage of the polysemy of concepts like "sleep," "experimental psychology," and "psychism." This article discusses his role in the context of emerging French psychology in the mid- to late 19th century. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  11. Formative factors of the Maria Åkerblom movement

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    Gustav Björkstrand


    Full Text Available The Åkerblom movement exemplifies the best known impact on the cultural and religious environment of Swedish Finland, of a geographically and historically extensive phenomenon—the prophet movement. An obvious prerequisite for the emergence of a prophet movement is the prophet figure. The character and development of the movement are, to a great extent, dependent on the background and personality of this figure. The adolescence of Ida Maria Åkerblom (IMÅ, a cottar's daughter, born in Snappertuna in rural West Nyland in 1898, was both materially and spiritually barren. In matter of religion, she grew up in an atmosphere of piety best described as 'traditional and formalistic', with elements of evangelistic and later, also Anglo-Saxon revivalist piety. On the day on which IMÅ's confirmation priest and curate at Snappertuna, Karl-Erik Lindström died, IMÅ assumed the role of prophet and preacher, according to her account, after a severe illness. Lying in bed, she prophesied, while in a somnambulic state, imminent periods of hardship, and depicted her heavenly vision.

  12. Sleepwalking associated with hyperthyroidism. (United States)

    Ajlouni, Kamel M; Ahmad, Azmi T; El-Zaheri, Mohamed M; Al-Zahiri, Mohammad M; Ammari, Fawwaz L; Jarrah, Nadim S; AbuJbara, Mousa A; Ajlouni, Heitham K; Daradkeh, Tewfik K


    To report several cases of hyperthyroidism in patients presenting with the unusual symptom of sleepwalking and to discuss the possible pathophysiologic basis for this novel association. After encountering and reporting the first case of new-onset somnambulism in a patient presenting with thyrotoxicosis at our institution, we routinely inquired about the sleep history of patients with thyrotoxicosis, questioning both the patients and family members when applicable. Those patients who actually had sleepwalking episodes coinciding with the onset of thyrotoxicosis underwent close follow-up, and the relationship between the sleepwalking and the results of thyroid function tests was analyzed. In addition, we reviewed the literature on psychiatric disorders and sleep problems, and the pathophysiologic rationale for a cause-and-effect relationship is discussed. We collected 8 cases of patients with new-onset sleepwalking episodes that coincided with the start of thyrotoxicosis. The disappearance of the sleepwalking with successful achievement of euthyroidism supports a cause-and-effect relationship. This hypothesis is further supported by the absence of a family history, the adult onset, and the relapse of sleepwalking in 2 of the patients when their thyrotoxicosis became poorly controlled as a result of noncompliance with medications and its subsequent disappearance with reachievement of euthyroidism. Of note, such a presentation was seen only in patients with thyrotoxicosis caused by diffuse toxic goiter or Graves' disease and never in patients with other causes of thyrotoxicosis. New-onset sleepwalking could be caused by thyrotoxicosis or, more specifically, by thyrotoxicosis resulting from diffuse toxic goiter. The mechanism is hypothesized to be related to the combination of prolongation of non-rapid eye movement sleep and the associated fatigue. Specific inquiry about this unusual presentation of thyrotoxicosis is encouraged, and more studies are needed to confirm

  13. Dream-Enacting Behaviors in a Normal Population (United States)

    Nielsen, Tore; Svob, Connie; Kuiken, Don


    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 dream-talking 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

  14. Violência durante o sono Violent behavior during sleep

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    Dalva Poyares


    Full Text Available 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 auto-infligidos 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.Cases of violent behavior during sleep have been reported in the literature. However, the incidence of violent behavior during sleep is not known. One epidemiological study showed that approximately 2% of the general population, predominantly males, presented violent behavior while asleep. In the present study, the authors describe clinical and medico-legal aspects involved in violent behavior investigation. Violent behavior refers to self-injury or injury to another during sleep. It happens most frequently following partial awakening in the context of arousal disorders (parasomnias. The most frequently diagnosed sleep disorders are REM behavior disorder and somnambulism. Violent behavior might be precipitated by stress, use of alcohol or drugs, sleep deprivation or fever.

  15. Non-Rapid Eye Movement Sleep Parasomnias and Migraine: A Role of Orexinergic Projections

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    Antonietta Messina


    Full Text Available IntroductionSleep and migraine share a common pathophysiological substrate, although the underlying mechanisms are unknown. The serotonergic and orexinergic systems are both involved in the regulation of sleep/wake cycle, and numerous studies show that both are involved in the migraine etiopathogenesis. These two systems are anatomically and functionally interconnected. Our hypothesis is that in migraine a dysfunction of orexinergic projections on the median raphe (MR nuclei, interfering with serotonergic regulation, may cause Non-Rapid Eye Movement parasomnias, such as somnambulism.Hypothesis/theoryActing on the serotonergic neurons of the raphe nuclei, the dysfunction of orexinergic neurons would lead to a higher release of serotonin. The activation of serotonergic receptors located on the walls of large cerebral vessels would lead to abnormal vasodilatation and consequently increase transmural pressure. This process could activate the trigeminal nerve terminals that innervate vascular walls. As a consequence, there is activation of sensory nerve endings at the level of hard vessels in the meninges, with release of pro-inflammatory peptides (e.g., substance P and CGRP. Within this hypothetical frame, the released serotonin could also interact with trigeminovascular afferents to activate and/or facilitate the release of the neuropeptide at the level of the trigeminal ganglion. The dysregulation of the physiological negative feedback of serotonin on the orexinergic neurons, in turn, would contribute to an alteration of the whole system, altering the sleep–wake cycle.ConclusionSerotonergic neurons of the MR nuclei receive an excitatory input from hypothalamic orexin/hypocretin neurons and reciprocally inhibit orexin/hypocretin neurons through the serotonin 1A receptor (or 5-HT1A receptor. Considering this complex system, if there is an alteration it may facilitate the pathophysiological mechanisms involved in the migraine, while it may produce

  16. Increasing trends of sleep complaints in the city of Sao Paulo, Brazil. (United States)

    Santos-Silva, Rogerio; Bittencourt, Lia Rita Azeredo; Pires, Maria Laura Nogueira; de Mello, Marco Tulio; Taddei, Jose Augusto; Benedito-Silva, Ana Amelia; Pompeia, Celine; Tufik, Sergio


    The aim of this study was to compare the prevalence of sleep habits and complaints and to estimate the secular trends through three population-based surveys carried out in 1987, 1995, and 2007 in the general adult population of the city of Sao Paulo, Brazil. Surveys were performed using the same three-stage cluster-sampling technique in three consecutive decades to obtain representative samples of the inhabitants of Sao Paulo with respect to gender, age (20-80 years), and socio-economic status. Sample sizes were 1000 volunteers in 1987 and 1995 surveys and 1101 in a 2007 survey. In each survey, the UNIFESP Sleep Questionnaire was administered face-to-face in each household selected. For 1987, 1995, and 2007, respectively, difficulty initiating sleep (weighted frequency %; 95% CI) [(13.9; 11.9-16.2), (19.15; 16.8-21.6), and (25.0; 22.5-27.8)], difficulty maintaining sleep [(15.8; 13.7-18.2), (27.6; 24.9-30.4), and (36.5; 33.5-39.5)], and early morning awakening [(10.6; 8.8-12.7), (14.2; 12.2-16.5), and (26.7; 24-29.6)] increased in the general population over time, mostly in women. Habitual snoring was the most commonly reported complaint across decades and was more prevalent in men. There was no statistically significant difference in snoring complaints between 1987 (21.5; 19.1-24.2) and 1995 (19.0; 16.7-21.6), but a significant increase was noted in 2007 (41.7; 38.6-44.8). Nightmares, bruxism, leg cramps, and somnambulism complaints were significantly higher in 2007 compared to 1987 and 1995. All were more frequent in women. This is the first study comparing sleep complaints in probabilistic population-based samples from the same metropolitan area, using the same methodology across three consecutive decades. Clear trends of increasing sleep complaints were observed, which increased faster between 1995 and 2007 than from 1987 to 1995. These secular trends should be considered a relevant public health issue and support the need for development of health care and

  17. Síndrome de ingesta nocturna como efecto colateral del zolpidem Sleep related eating disorders as a side effect of zolpidem

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    Stella Maris Valiensi


    Full Text Available El zolpidem es una droga hipnótica utilizada para el tratamiento del insomnio. Disminuye la latencia del sueño, el número total de despertares y aumenta el tiempo total del sueño respetando en general su arquitectura. Se cree que aumenta la fase 3 del sueño lento profundo. Nuestro objetivo es comunicar 8 casos de síndrome de ingesta nocturna relacionado al sueño y conductas automáticas complejas asociadas a sonambulismo como efecto colateral del zolpidem. Se analizaron las historias clínicas de 8 pacientes tratados con zolpidem que referían ingesta nocturna de alimentos con amnesia total o parcial del episodio. Se presentan 6 mujeres y 2 hombres, entre 32 y 72 años (media: 58 años, 7 tratados con zolpidem 10 mg/noche y 1 con zolpidem 12.5 mg/noche de liberación prolongada. El tiempo de exposición previo al desarrollo de eventos fue de 1 a 180 días (media de 39.8. El número de episodios relatados era de 1 a 8/noche (media 2.5 asociado con amnesia. Los episodios desaparecieron por completo en el 100% de los casos al suspender la medicación. El síndrome de ingesta nocturna relacionado al sueño es una parasomnia de sueño lento profundo que consiste en episodios de ingesta de alimento o bebida durante la noche, con amnesia parcial o completa del episodio. El zolpidem podría inducir el síndrome de ingesta nocturna relacionado al sueño en aproximadamente el 1% de pacientes, aunque creemos que es un efecto adverso que está subdiagnosticado. Se resuelve simplemente suspendiendo la medicación.Zolpidem is a hypnotic drug used in sleep disorders. It binds selectively to alpha 1 subunit of the GABA A benzodiazepine receptor. Zolpidem reduces sleep latency, number of arousals and increases the total time of sleep. However, it is considered that it may increase phase 3 of non rapid eye movement sleep, where somnambulism can take place. Our aim is to report 8 cases of sleep related eating disorders associated with the use of this drug

  18. [Dissociative disorders: from Janet to DSM-IV]. (United States)

    Nakatani, Y


    I reviewed the literature on dissociation and dissociative disorders from Pierre Janet to DSM-IV, and examined the current trends in research. Janet's theory on hysteria is multifaceted, and is based on three psychological models. Based on a hierarchical model, Janet related hysteric symptoms to the activities within the lower strata of mental hierarchy (automatisms psychologiques), which were demonstrably shown in somnambulism. A second model was based on the concept of a psychological system, which was hypothetically composed of ideas, images, feelings, sensations, and movements. According to this model, dissociation of psychological functions was fundamental to the mechanism of hysteria: loss of integration was thought to engender fixed ideas (ideas fixes) and to lead to the development of a system totally isolated from the whole personality system. Janet also attempted to explain various mental disorders using an economic model. He referred to a loss of equilibration between psychological force and psychological tension. Thus, an unexpected emotional experience was conceived to cause a consumption of reserved psychological force, which was in turn followed by exhaustion associated with hysteric symptoms. Whereas most current researchers regard Janet as the first to study psychological trauma as a principal cause of dissociation, I feel it is important to note that he also emphasized the role of stigmata, i.e., permanent traits of hysteric patients, which were represented as a suggestibility and a tendency toward a narrowing of the consciousness field. Discussion about dissociation and its relation to trauma all but disappeared after Janet. However, during the Second World War and post-war period, some psychiatrists began to pay attention to two emerging phenomena: a high incidence of dissociative symptoms such as fugue and amnesia among combatants, and traumatic neurosis frequently observed among ex-inmates of concentration camps. In the 1970s, interest in