Simeon D
Depersonalisation disorder: a contemporary overview.
CNS Drugs. 2004;18(6):343-54.
Depersonalisation disorder is characterised by prominent depersonalisation and often derealisation, without clinically notable memory or identity disturbances. The disorder has an approximately 1 : 1 gender ratio with onset at around 16 years of age. The course of the disorder is typically long term and often continuous. Mood, anxiety and personality disorders are often comorbid with depersonalisation disorder but none predict symptom severity.The most common immediate precipitants of the disorder are severe stress, depression and panic, and marijuana and hallucinogen ingestion. Depersonalisation disorder has also been associated with childhood interpersonal trauma, in particular emotional maltreatment.Neurochemical findings have suggested possible involvement of serotonergic, endogenous opioid and glutamatergic NMDA pathways. Brain imaging studies in depersonalisation disorder have revealed widespread alterations in metabolic activity in the sensory association cortex, as well as prefrontal hyperactivation and limbic inhibition in response to aversive stimuli. Depersonalisation disorder has also been associated with autonomic blunting and hypothalamic-pituitary-adrenal axis dysregulation.To date, treatment recommendations and guidelines for depersonalisation disorder have not been established. There are few studies assessing the use of pharmacotherapy in this disorder. Medication options that have been reported include clomipramine, fluoxetine, lamotrigine and opioid antagonists. However, it does not appear that any of these agents have a potent anti-dissociative effect. A variety of psychotherapeutic techniques has been used to treat depersonalisation disorder (including trauma-focused therapy and cognitive-behavioural techniques), although again none of these have established efficacy to date. Overall, novel therapeutic approaches are clearly needed to help individuals experiencing this refractory disorder. [Abstract]

Simeon D, Knutelska M, Nelson D, Guralnik O
Feeling unreal: a depersonalization disorder update of 117 cases.
J Clin Psychiatry. 2003 Sep;64(9):990-7.
BACKGROUND: Despite a surge of interest and literature on depersonalization disorder in recent years, a large series of individuals with the disorder has not been described to date. In this report, we systematically elucidate the phenomenology, precipitants, antecedents, comorbidity, and treatment history in such a series. METHOD: 117 adult subjects with depersonalization disorder (DSM-III-R/DSM-IV criteria) consecutively recruited to a number of depersonalization disorder research studies were administered structured and semistructured diagnostic interviews and the Dissociative Experiences Scale. Data were gathered from 1994 to 2000. RESULTS: The illness had an approximately 1:1 gender ratio with onset around 16 years of age. The course was typically chronic and often continuous. Illness characteristics such as onset, duration, and course were not associated with symptom severity. Mood, anxiety, and personality disorders were frequently comorbid, but none predicted depersonalization severity. The most common immediate precipitants of the disorder were severe stress, depression, panic, marijuana ingestion, and hallucinogen ingestion, and none of these predicted symptom severity. Negative affects, stress, perceived threatening social interaction, and unfamiliar environments were some of the more common factors leading to symptom exacerbation. Conversely, comforting interpersonal interactions, intense emotional or physical stimulation, and relaxation tended to diminish symptom intensity. There were no significant gender differences in the clinical features of the disorder. In this sample, depersonalization tended to be refractory to various medication and psychotherapy treatments. CONCLUSION: The characteristics of depersonalization disorder found in this sample, the largest described to date, are in good accord with previous literature. The study highlights the need for novel therapeutic approaches to treat depersonalization disorder. Novel medication classes, as well as novel psychotherapeutic techniques that build on the reported symptom fluctuation factors, may prove helpful in the future. [Abstract]

Hunter EC, Sierra M, David AS
The epidemiology of depersonalisation and derealisation. A systematic review.
Soc Psychiatry Psychiatr Epidemiol. 2004 Jan;39(1):9-18.
BACKGROUND: Symptoms of depersonalisation (DP) and derealisation (DR) are increasingly recognised in both clinical and non-clinical settings, but their importance and underlying pathophysiology is only now being addressed. METHODS: This paper is a systematic review of the current state of knowledge about the prevalence of depersonalisation and derealisation using computerised databases and citation searches. All potential studies were examined and numerical data included. Three categories of study are reviewed: questionnaire and interview surveys of selected student and non-clinical samples; population-based community surveys using standardised diagnostic interviews; and clinical surveys of depersonalisation/derealisation symptoms occurring within inpatients with psychiatric disorders. In addition, we present newly analysed data of the prevalence of depersonalisation/derealisation from five large population-based studies. RESULTS: Epidemiological surveys demonstrate that transient symptoms of depersonalisation/derealisation in the general population are common, with a lifetime prevalence rate of between 26 and 74% and between 31 and 66% at the time of a traumatic event. Community surveys employing standardised diagnostic interviews reveal rates of between 1.2 and 1.7 % for one month prevalence in a UK sample and a 2.4% current prevalence rate in a Canadian sample. Current prevalence rates in samples of consecutive inpatient admissions are reported between 1 and 16%, although screening measures employed may have resulted in these being an underestimate. Prevalence rates in clinical samples of specific psychiatric disorders vary between 30% of war veterans with PTSD and 60% of those with unipolar depression. There is a high prevalence within panic disorder with rates varying from 7.8 to 82.6%. DISCUSSION: DP and DR symptoms are common in normal and psychiatric populations, but prevalence estimates are hampered by inconsistent definitions and the use of variable time-frames. Population-based surveys using diagnostic interviews yield prevalence rates of clinically significant DP/DR in the region of 1-2%. Surveys of clinical populations in which common screening and assessment instruments were used also yield consistently high prevalence rates. The use of reliable diagnostic assessments and rating scales is needed. The relationship between DP/DR and certain other psychiatric disorders (e. g. panic) suggests possible common pathophysiological or aetiological factors. [Abstract]

Baker D, Hunter E, Lawrence E, Medford N, Patel M, Senior C, Sierra M, Lambert MV, Phillips ML, David AS
Depersonalisation disorder: clinical features of 204 cases.
Br J Psychiatry. 2003 May;182428-33.
BACKGROUND: Depersonalisation disorder is a poorly understood and underresearched syndrome. AIMS: To carry out a large and comprehensive clinical and psychopathological survey of a series of patients who made contact with a research clinic. METHOD: A total of 204 consecutive eligible referrals were included: 124 had a full psychiatric examination using items of the Present State Examination to define depersonalisation/derealisation and 80 had either a telephone interview (n=22) or filled out a number of self-report questionnaires. Cases assessed were diagnosed according to DSM-IV criteria. RESULTS: The mean age of onset was 22.8 years; early onset was associated with greater severity. There was a slight male preponderance. The disorder tended to be chronic and persistent. Seventy-one per cent met DSM-IV criteria for primary depersonalisation disorder. Depersonalisation symptom scores correlated with both anxiety and depression and a past history of these disorders was commonly reported. 'Dissociative amnesia' was not prominent. CONCLUSIONS: Depersonalisation disorder is a recognisable clinical entity but appears to have significant comorbidity with anxiety and depression. Research into its aetiology and treatment is warranted. [Abstract]

Moyano O, Claudon P, Colin V, Svatos J, Thiébaut E
[Study of dissociative disorders and depersonalization in a sample of young adult French population]
Encephale. 2001 Nov-Dec;27(6):559-69.
Questioned by several researches about dissociative disorders, the authors study differences established on the nosographic register, through a quantitative study and a psychodynamic argumentation in a sample of french population. From the utilisation of the Dissociative Experiences Scale (DES) created by Bernstein E and Putnam FW (1986), which is an excellent screening tool for dissociative disorders and constructed on DSM II diagnostic criterions, the authors will show the interest of a psychodynamic analysis of dissociative disorders, in the face of the diagnostic difficulty in relation to several approaches of this concept. This difficulty is studied giving the background to dissociative disorders and depersonalization. Ionescu (1999) shows that between 1890 and 1910 dissociation represents one of major themes of psychology, psychopathology and psychiatry. Then, this interest about dissociation decreases and will be almost non-existent in the middle of the twentieth century. The interest for dissociative disorder will grow in the eighties with north-american studies about multiple personality disorders. Until 1980, dissociative disorders exist in DSM II as a list of symptoms included into hysterical neurosis, among the conversive disorders. In 1980, the publication of DSM III replaces the notion of hysteria with the notion of dissociative disorder. In this way, we can see on the one hand somatoform disorders quarterly corresponding to the ancient version of conversive hysteria, and on the other hand dissociative disorders characterized by a perturbation of consciousness, memory, identity or perception of environment. In 1994, The DSM IV delete the notion of hysteria and neurosis and keeps only the notion of dissociative disorders. They include now the five following categories: dissociative amnesia, dissociative fugue, depersonalization disorder, dissociative identity disorder, dissociative disorder not otherwise specified (including derealization). Depersonalization disorders consist of "persistent or recurrent episodes of depersonalization characterized by a feeling of detachment or estrangement from one's self. The individual may feel like an automation or like he or she is living in a dream or movie" (DSM IV). Depersonalization disorder cannot be diagnosed if it is part of schizophrenia, panic disorder, acute stress disorder or dissociative identity disorder. Various depressive disorders, hypocondriasis or obsessive-compulsive disorders can accompany depersonalization disorder. The first purpose of this study will search the frequency of dissociative disorders and depersonalization in a sample of normal population. Further, the inclusion of depersonalization amongst dissociative disorders seems not so evident: depersonalization belongs to self-consciousness disorder in french psychiatry. This fact seems more logical insofar as dissociative disorders have all together a memory and consciousness perturbation, and this perturbation is missing from depersonalization's feeling. The second purpose will be to clarify and specify the particularity of depersonalization among dissociative diorders, from the psychopathological point of view. METHODOLOGY: The sample (n = 248) is made up of french young adults aged 17 to 30 (mean age = 20, SD = 15 and 24% is male population). Subjects were streamming from universities. The screening tool which was used is the Dissociative Experiences Scale, a 28-item patient questionnaire regarding various dissociative symptoms. The subject is asked to indicate the percentage of time, to the nearest 5%, that particular symptom is experienced. The score is made by adding the various percentages and finding a mean that is expressed in numbers from 0 to 100. Normal scores are in the range of 5 to 15 in american adults. RESULTS: The utilization of principal component analysis (PCA) with varimax rotation is justified by the will to compare this study with American's studies. The mean score obtained is 17.44%, and 13.3% of the scores exceed a psychiatric threshold at 30%. The descriptive analysis shows that the component 1 (PCA without varimax rotation) represents 33.02% of total explained variance. This result demonstrates that the structure of the DES is based on one concept, the same as the american population, it is the concept of dissociation. The Principal Component Analysis with varimax rotation of the DES ratings yielded a tree-factor solution: imaginative absorption (F1), depersonalization-derealization (F2) and dissociative amnesia (F3). Mean score for each factor is respectively: F1 = 21.56%, F2 = 13.95%, F3 = 11.04%. DES reliability was studied through computation of Cronbach's coefficient (0.92). The PCA with varimax rotation brings to the fore a full dissociative disorder without any trouble of memory and consciousness. This fact questions again once more the link between hysteria and dissociative disorders. There is here a clinical distinction between depersonalization-derealization and other dissociative disorders. Indeed, the absence of significant alteration of memory and conscience is specific of depersonalization and derealization in this study. CONCLUSION: Finally, this study concurs with DSM IV dissociative criterions. At last, one factor of PCA is composed by the association of depersonalization and derealization, in contradiction with DSM IV definition. This result shows that, into the french population, we cannot divide the two concepts. [Abstract]

Simeon D, Guralnik O, Schmeidler J, Sirof B, Knutelska M
The role of childhood interpersonal trauma in depersonalization disorder.
Am J Psychiatry. 2001 Jul;158(7):1027-33.
OBJECTIVE: In contrast to trauma's relationship with the other dissociative disorders, the relationship of trauma to depersonalization disorder is unknown. The purpose of this study was to systematically investigate the role of childhood interpersonal trauma in depersonalization disorder. METHOD: Forty-nine subjects with DSM-IV depersonalization disorder and 26 healthy comparison subjects who were free of lifetime axis I and II disorders and of comparable age and gender were administered the Dissociative Experiences Scale and the Childhood Trauma Interview, which measures separation or loss, physical neglect, emotional abuse, physical abuse, witnessing of violence, and sexual abuse. RESULTS: Childhood interpersonal trauma as a whole was highly predictive of both a diagnosis of depersonalization disorder and of scores denoting dissociation, pathological dissociation, and depersonalization. Emotional abuse, both in total score and in maximum severity, emerged as the most significant predictor both of a diagnosis of depersonalization disorder and of scores denoting depersonalization but not of general dissociation scores, which were better predicted by combined emotional and sexual abuse. The majority of the perpetrators of emotional abuse were either or both parents. Although different types of trauma were modestly correlated, only a few of these relationships were statistically significant, underscoring the importance of comprehensively considering different types of trauma in research studies. CONCLUSIONS: Childhood interpersonal trauma and, in particular, emotional abuse may play a role in the pathogenesis of depersonalization disorder. Compared to other types of childhood trauma, emotional maltreatment is a relatively neglected entity in psychiatric research and merits more attention. [Abstract]

Simeon D, Gross S, Guralnik O, Stein DJ, Schmeidler J, Hollander E
Feeling unreal: 30 cases of DSM-III-R depersonalization disorder.
Am J Psychiatry. 1997 Aug;154(8):1107-13.
OBJECTIVE: In contrast to the recent surge of interest in other dissociative disorders, DSM-III-R depersonalization disorder has not been thoroughly investigated and characterized. The authors systematically elucidated its phenomenology, comorbidity, traumatic antecedents, and treatment history. METHOD: Thirty adult subjects (19 women and 11 men) were consecutively recruited and administered various structured and semistructured interviews as well as the self-rated Dissociative Experiences Scale. An age- and sex-matched normal comparison group was also recruited. RESULTS: The mean age at onset of depersonalization disorder was 16.1 years (SD = 5.2). The illness had a chronic course that was usually continuous but sometimes episodic. Severe distress and high levels of interpersonal impairment were characteristic. Unipolar mood and anxiety disorders were common, but none emerged as specifically related to the depersonalization. A wide variety of personality disorders was manifested; avoidant, borderline, and obsessive-compulsive were most common. Although not highly traumatized, the subjects with depersonalization disorder reported significantly more childhood trauma than the normal comparison subjects. Depersonalization had been typically treatment refractory; only serotonin reuptake inhibitors and, to a lesser extent, benzodiazepines had been of any therapeutic benefit. CONCLUSIONS: This study supports the conceptualization of depersonalization disorder as a distinct disorder with a characteristic course that is independent of mood, anxiety, and personality symptoms. A subtle relationship may exist between childhood trauma and depersonalization disorder that merits further investigation. The disorder appears to be highly treatment refractory, and prospective treatment trials are warranted. [Abstract]

Carrion VG, Steiner H
Trauma and dissociation in delinquent adolescents.
J Am Acad Child Adolesc Psychiatry. 2000 Mar;39(3):353-9.
OBJECTIVES: To assess history of trauma and dissociation in a group of juvenile delinquents and to assess how adolescents would respond to a structured interview for dissociative symptoms. METHOD: Sixty-four adolescents in juvenile probation hall participated in 2 investigational sessions in 1996-1997. For session 1 they answered the Childhood Trauma Questionnaire (CTQ), the Response Evaluation Measure for Youth-71 (REMY-71), and the Weinberger Adjustment Inventory. For session 2 they were given the Childhood Trauma Interview (CTI) and the Structured Clinical Interview for DSM-IV Dissociative Disorders (SCID-D). RESULTS: In this sample 28.3% met criteria for a dissociative disorder and 96.8% endorsed a history of traumatic events. There were significant positive correlations between CTI and CTQ trauma scores and SCID-D and REMY-71 dissociative symptoms. All dissociative symptoms were endorsed, but depersonalization was the most common experience. There was a lack of congruence between the different methods of assessing dissociation. CONCLUSIONS: This study provides support for an early link between history of trauma and dissociation. Adolescents were able to answer questions from a structured interview assessing dissociation. [Abstract]

Lambert MV, Senior C, Phillips ML, Sierra M, Hunter E, David AS
Visual imagery and depersonalisation.
Psychopathology. 2001 Sep-Oct;34(5):259-64.
Twenty-eight people diagnosed with depersonalisation disorder (DD) were assessed using self-report measures of imagery ability in relation to a range of symptoms and in comparison with age- and sex-matched controls. It was found that symptoms of depersonalisation as well as other dissociative symptoms and depressed mood correlated with impaired ability to generate visual images. This was particularly evident with images pertaining to the self and other people as opposed to objects. A subgroup of 10 patients was tested on a neuropsychological battery of visual perception tests and found to be unimpaired compared with normal controls and patients with obsessive compulsive disorder, despite subjective impairments in imagery and high symptom scores. The findings add further weight to the distinctions made between imagery and perceptual processes. [Abstract]

Guralnik O, Schmeidler J, Simeon D
Feeling unreal: cognitive processes in depersonalization.
Am J Psychiatry. 2000 Jan;157(1):103-9.
OBJECTIVE: Depersonalization disorder is characterized by a detachment from one's sense of self and one's surroundings that leads to considerable distress and impairment yet an intact testing of reality. Depersonalized individuals often report difficulties in perception, concentration, and memory; however, data on their cognitive profiles are lacking. METHOD: Fifteen patients with depersonalization disorder were compared to 15 matched normal comparison subjects on a comprehensive neuropsychological test battery that assessed cognitive function. RESULTS: The subjects with depersonalization disorder showed a distinct cognitive profile. They performed significantly worse than the comparison subjects on certain measures of attention, short-term visual and verbal memory, and spatial reasoning within the context of comparable intellectual abilities. CONCLUSIONS: The authors propose that depersonalization involves alterations in the attentional and perceptual systems, specifically in the ability to effortfully control the focus of attention. These early encoding deficits are hypothesized to have a deleterious effect on the short-term memory system; they manifest as deficits in the ability to take in new information but not in the ability to conceptualize and manipulate previously encoded information. [Abstract]

Oae H, Abiru T, Domon Y
[Two types of depersonalization--reconsideration from a descriptive-phenomenological view point]
Seishin Shinkeigaku Zasshi. 2001;103(5):411-25.
The term depersonalization has been vaguely used in clinical contexts and there is confusion over its nosological positioning. Although the syndrome has been assigned a niche of its own in the European psychiatric taxonomy, the American's Diagnostic and Statistical Manual of Mental Disorders (DSM-III, IV) labeled it under the term Dissociative Disorder. The latter, which does not agree with the classical theory of Janet, seems to have no basis on traditional psychopathology and is not derived from any dissociative theories. In this paper the descriptive characteristics of depersonalization are discussed with regard to the features of "observing self" and the relationship between experiences and selves, according to which the authors distinguish two types of depersonalization: an "excessive-self-reflecting type" and an "absorbed-in-experience type". Whereas the former coinsides with the typical depersonalization neurosis, in which excessive self-reflection plays an important role in reducing the sense of reality, in the latter over-absorption in some situations leads the patient to construct a wall to block out reality. We suggest that in making a distinction between these two types, the psychopathology of depersonalization will be better clarified. [Abstract]

Simeon D, Guralnik O, Knutelska M, Schmeidler J
Personality factors associated with dissociation: temperament, defenses, and cognitive schemata.
Am J Psychiatry. 2002 Mar;159(3):489-91.
OBJECTIVE: The purpose of this study was to investigate temperamental, psychodynamic, and cognitive factors associated with dissociation. METHOD: Fifty-three subjects with DSM-IV-defined depersonalization disorder and 22 healthy comparison subjects were administered the Dissociative Experiences Scale, the Tridimensional Personality Questionnaire, the Defense Style Questionnaire, and the Schema Questionnaire. RESULTS: Subjects with depersonalization disorder demonstrated significantly greater harm-avoidant temperament, immature defenses, and over-connection and disconnection cognitive schemata than comparison subjects. Within the group of subjects with depersonalization disorder, dissociation scores significantly correlated with the same variables. CONCLUSIONS: Particular personality factors may render individuals more vulnerable to dissociative symptoms. Risk factors associated with dissociative disorders merit further study. [Abstract]

Moroz BT, Nuller IuL, Ustimova IN, Andreev BV
[Study of pain sensitivity based on the indicators of electro- odontometry in patients with depersonalization and depressive disorders]
Zh Nevropatol Psikhiatr Im S S Korsakova. 1990;90(10):81-2.
Electroodontometry was used to examine the pain threshold and sensation threshold in patients with depersonalization, endogenous depression and in mentally healthy test subjects. The strongest differences in the thresholds were found on the anterior teeth. The patients with depersonalization manifested a considerable rise of the sensation threshold and to an ever greater degree of the pain threshold. In patients suffering from endogenous depression, both thresholds were decreased and coincided almost completely. It is likely that this fact is associated with a relatively higher incidence of the painful syndrome in patients suffering from depression. [Abstract]

Levin R, Sirof B, Simeon D, Guralnick O
Role of fantasy proneness, imaginative involvement, and psychological absorption in depersonalization disorder.
J Nerv Ment Dis. 2004 Jan;192(1):69-71. [Abstract]

Berrios GE, Sierra M
Depersonalization: a conceptual history.
Hist Psychiatry. 1997 Jun;8(30 pt 2):213-29.
As with other clinical phenomena, the historical analysis of the term, concepts and behaviours involved in the construction of 'depersonalization' should provide researchers with an essential frame for its empirical study. Before the term was coined in 1898, and under a variety of names, behaviours typical of 'depersonalization' were reported by Esquirol, Zeller, Billod, and Griesinger. The word 'depersonnalisation, derived from a usage in Amiel's Journal intime, was first used in a technical sense by Ludovic Dugas. The new disorder has since been explained as resulting from pathological changes in the sensory system, memory, affect, body image and self-experience. During the 1930s, evolutionary views became popular, particularly in the work of Mayer-Gross. The unclear conceptual boundaries of depersonalization still invite confusion and often enough fragments of what used to be its core-behaviour are used to diagnose the disorder. Depersonalization has of late become subsumed under the dissociative disorders. The definitional instability of the latter, however, has caused further complications to the study of depersonalization. It is recommended that the term is used to refer only to the original core-behaviour as this has shown adequate stability. [Abstract]

Sierra M, Berrios GE
The phenomenological stability of depersonalization: comparing the old with the new.
J Nerv Ment Dis. 2001 Sep;189(9):629-36.
The view that depersonalization is a stable syndrome became well established during the first half of the 20th century. Current operational definitions restrict depersonalization to the experience of unreality. This is likely to neglect clinical features of potential neurobiological relevance. By using the year 1946 as the dividing line, 200 cases of depersonalization disorder reported in the medical literature since 1898 were divided into two historical groups (1 and 2). The groups were then compared in terms of 18 phenomenological variables with a sample of 45 prospective cases of DSM-IV depersonalization disorder (group 3 or gold standard). Groups 1 and 2 differed in terms of their symptom profile, but the highest frequency that symptoms achieved in either group did not differ from the rates identified in group 3. A core of (invariable) symptoms, including emotional numbing, visual derealization, and altered body experience, was present throughout. These high rates of spontaneous reporting in all three groups may be explained by the fact that they all are accompanied by specific distress. With the exception of heightened self-observation and altered time experiencing, all other symptoms were significantly lower in group 2. The results suggest that the phenomenology of depersonalization has remained stable over the last 100 years. Our study found differences in frequency for some symptoms, but these are likely to have resulted from reporting biases, themselves governed by changing theoretical views. Clinical descriptions became poorer as the present is approached. This cannot be solely explained on the basis of empirical progress, and it is likely that theoretical biases also play a role. Because the neurobiological relevance of the symptoms of depersonalization remains unknown, it makes sense to continue collecting as many symptoms as possible, thereby avoiding both biased selection or premature closure. [Abstract]

Lambert MV, Senior C, Phillips ML, David AS
Depersonalization in cyberspace.
J Nerv Ment Dis. 2000 Nov;188(11):764-71.
We explored the possibility of carrying out clinical research on the Internet. To do so, we compared psychometric and demographic variables between two groups of sufferers of depersonalization disorder, one recruited via the Internet, the other from outpatients attending the Depersonalization Research Unit. No differences were found in demographics or features of depersonalization. Those seen in the clinic were, however, significantly more depressed. We then explored the answers to several questions posted on a depersonalization bulletin board by a second group of Internet users. Useful information on symptoms, precipitants, and treatment was gained. It is concluded that the Internet could become a valuable tool in clinical psychiatric research. [Abstract]

Simeon D, Knutelska M, Nelson D, Guralnik O, Schmeidler J
Examination of the pathological dissociation taxon in depersonalization disorder.
J Nerv Ment Dis. 2003 Nov;191(11):738-44.
In recent years, the pathologic dissociation taxon developed by Waller, Putnam, and Carlson (Psychological Methods 1:300-321, 1996) from a Dissociative Identity Disorder (DID) sample has been increasingly used in studies of dissociation in general. However, the taxon's convergence with dissociative diagnoses other than DID, as well as the taxon's central premise that pathologic dissociation is a categorical rather than a dimensional construct, remain areas of exploration. This report examines the applicability of the pathologic dissociation taxon to Depersonalization Disorder (DPD). The Dissociative Experiences Scale was administered to 100 consecutively recruited DPD subjects diagnosed by semistructured clinical interview and by the SCID-D. Taxon membership probability was calculated using the recommended SAS scoring program. Approximately 2/3 of subjects (N = 64) had a very high probability (>.80) of belonging to the taxon, while 1/3 of subjects had a very low probability (<.10) of belonging to the taxon. A taxon cutoff score of 13 yielded an 81% sensitivity in detecting the presence of DPD. The modest convergence between taxonic membership and clinical dissociative disorder diagnosis suggests that the taxon may have important limitations in its use, at least when applied to DPD in its current form. As previously, we continue to recommend a low taxon cutoff score (13) for the sensitive detection of depersonalization disorder. The inference that pathologic dissociation is a unitary and categorical entity is also discussed. [Abstract]

Sierra M, Berrios GE
The Cambridge Depersonalization Scale: a new instrument for the measurement of depersonalization.
Psychiatry Res. 2000 Mar 6;93(2):153-64.
Existing self-rating scales to measure depersonalization either show dubious face validity or fail to address the phenomenological complexity of depersonalization. Based on a comprehensive study of the phenomenology of this condition, a new self-rating depersonalization questionnaire was constructed. The Cambridge Depersonalization Scale is meant to capture the frequency and duration of depersonalization symptoms over the 'last 6 months'. It has been tested on a sample of 35 patients with DSM-IV depersonalization disorder, 22 with anxiety disorders, and 20 with temporal lobe epilepsy. Scores were compared against clinical diagnoses (gold standard) and correlated with the depersonalization subscale of the Dissociation Experiences Scale (DES). The scale was able to differentiate patients with DSM-IV depersonalization disorder from the other groups, and showed specific correlations with the depersonalization subscale of the DES (r=0.80; P=0.0007). The scale also showed high internal consistency and good reliability (Cronbach alpha and split-half reliability were 0.89 and 0.92, respectively). The instrument can, therefore, be considered as valid and reliable, and can be profitably used in both clinical and neurobiological research. [Abstract]

Simeon D, Guralnik O, Schmeidler J
Development of a depersonalization severity scale.
J Trauma Stress. 2001 Apr;14(2):341-9.
Our aim was to develop a clinician-rated scale assessing depersonalization severity for use in clinical trials of Depersonalization Disorder and trauma-related disorders in general. The 6-item Depersonalization Severity Scale (DSS) was administered to 63 participants with DSM-IV Depersonalization Disorder as diagnosed by the SCID-D, and its psychometric properties were examined. The sensitivity of the DSS and of the Dissociative Experiences Scale (DES) to treatment change was assessed in blinded, controlled settings. Individual items were widely distributed across the severity range. Interrater reliability was excellent and internal consistency was moderate. The DSS had high convergent and discriminant validity and was sensitive to treatment change. The DES was also sensitive to treatment change. We recommend piloting the DSS in future treatment trials of trauma-spectrum disorders. [Abstract]

Lambert MV, Senior C, Fewtrell WD, Phillips ML, David AS
Primary and secondary depersonalisation disorder: a psychometric study.
J Affect Disord. 2001 Mar;63(1-3):249-56.
INTRODUCTION: Depersonalisation may be part of a symptom-complex, a primary or a secondary disorder. Optimal methods of measurement and diagnosis have not been established. METHODS: We assessed 42 patients with primary or secondary depersonalisation, plus psychiatric and non-psychiatric controls using a variety of self-report questionnaire scales including the Beck depression and anxiety Inventories, and one developed by the authors (the Fewtrell Depersonalisation Scale (FDS)). The correlations between the scales and measures of anxiety and depression were calculated, as were sensitivity and specificity against an operational case definition. RESULTS: All the scales were highly correlated. All could distinguish depersonalisation cases from the rest but none could distinguish between primary and secondary depersonalisation disorder. Anxiety and especially depression were correlated with depersonalisation symptoms. The FDS had high sensitivity (85.7%) and specificity (92.3%) which compared favourably with other instruments. Patients with both derealisation and depersonalisation scored the highest on the FDS. DISCUSSION: Depersonalisation disorder comprises a measurable cluster of symptoms which may be quantified with the help of self-report scales. Primary and secondary forms overlap, with depressed mood a frequent feature. [Abstract]

Cox BJ, Swinson RP
Instrument to assess depersonalization-derealization in panic disorder.
Depress Anxiety. 2002;15(4):172-5.
There is a long history of scholarly interest on depersonalization-derealization (DD) and its role in clinical anxiety, but there is a paucity of appropriate assessment instruments available. Our objective was to develop and evaluate a self-report measure of DD for use with clinically anxious patients. Panic disorder patients (n=169) were surveyed about DD experiences and provided data on a new item pool for psychometric development. DD episodes were common and a 28-item Depersonalization-Derealization Inventory was found to possess good reliability and validity. DD appears to be prevalent and clinically relevant in panic disorder. Continued study of DD is warranted and may be facilitated by the availability of a suitable instrument with promising psychometric properties. A 12-item version of the instrument may be appropriate as a brief screen. [Abstract]

Simeon D, Guralnik O, Hazlett EA, Spiegel-Cohen J, Hollander E, Buchsbaum MS
Feeling unreal: a PET study of depersonalization disorder.
Am J Psychiatry. 2000 Nov;157(11):1782-8.
OBJECTIVE: The goal of this study was to assess brain glucose metabolism and its relationship to dissociation measures and clinical symptoms in DSM-IV depersonalization disorder. METHOD: Positron emission tomography scans coregistered with magnetic resonance images of eight subjects with depersonalization disorder were compared to those of 24 healthy comparison subjects. The two groups did not differ in age, sex, education, performance on a baseline neuropsychological battery, or performance on a verbal learning task administered during [(18)F]fluorodeoxyglucose uptake. A cortical analysis by individual Brodmann's areas was performed. RESULTS: Compared to the healthy subjects, subjects with depersonalization disorder showed significantly lower metabolic activity in right Brodmann's areas 22 and 21 of the superior and middle temporal gyri and had significantly higher metabolism in parietal Brodmann's areas 7B and 39 and left occipital Brodmann's area 19. Dissociation and depersonalization scores among the subjects with depersonalization disorder were significantly positively correlated with metabolic activity in area 7B. CONCLUSIONS: Depersonalization appears to be associated with functional abnormalities along sequential hierarchical areas, secondary and cross-modal, of the sensory cortex (visual, auditory, and somatosensory), as well as areas responsible for an integrated body schema. These findings are in good agreement with the phenomenological conceptualization of depersonalization as a dissociation of perceptions as well as with the subjective symptoms of depersonalization disorder. [Abstract]

Lambert MV, Sierra M, Phillips ML, David AS
The spectrum of organic depersonalization: a review plus four new cases.
J Neuropsychiatry Clin Neurosci. 2002 Spring;14(2):141-54.
Depersonalization and derealization are commonly reported in the general population as a response to stress. The symptoms have also been described in patients with a primary psychiatric or organic diagnosis, where their secondary status precludes a DSM-IV diagnosis of depersonalization disorder. The authors present 4 new cases of depersonalization in patients with an underlying organic condition, along with 47 cases from the literature in which the available information permits diagnosis of organic depersonalization. Information from case series documenting depersonalization in the context of medical illnesses is also presented and the underlying etiology discussed. Epilepsy and migraine appear to be the disorders most commonly associated with depersonalization. Left-sided temporal lobe dysfunction and anxiety are suggested as factors in the development of depersonalization; however, further studies are needed to determine the relationship. The introduction to the DSM-IV of an organic subtype of depersonalization disorder would facilitate research in this area. [Abstract]

Hollander E, Carrasco JL, Mullen LS, Trungold S, DeCaria CM, Towey J
Left hemispheric activation in depersonalization disorder: a case report.
Biol Psychiatry. 1992 Jun 1;31(11):1157-62.
Depersonalization disorder is classified in DSM-III-R (APA 1987) as a dissociative disorder characterized by altered perception or experience of the self. To date, there are no known reports of the neurobiological features of this disorder. We report clinical and biological correlates in a patient with depersonalization disorder previously unresponsive to a variety of anticonvulsant, monoamine oxidase inhibitor, and tricyclic antidepressant trials, but for whom fluoxetine partially reduced depersonalization symptoms, but not associated anxiety and depression. Neurophysiological, neuroanatomical and neuropsychological findings revealed left hemispheric frontal-temporal activation and decreased left caudate perfusion. These findings suggest a similarity to the neuropsychiatric data reported in obsessive-compulsive disorder patients. [Abstract]

Phillips ML, Medford N, Senior C, Bullmore ET, Suckling J, Brammer MJ, Andrew C, Sierra M, Williams SC, David AS
Depersonalization disorder: thinking without feeling.
Psychiatry Res. 2001 Dec 30;108(3):145-60.
Patients with depersonalization disorder (DP) experience a detachment from their own senses and surrounding events, as if they were outside observers. A particularly common symptom is emotional detachment from the surroundings. Using functional magnetic resonance imaging (fMRI), we compared neural responses to emotionally salient stimuli in DP patients, and in psychiatric and healthy control subjects. Six patients with DP, 10 with obsessive-compulsive disorder (OCD), and six volunteers were scanned whilst viewing standardized pictures of aversive and neutral scenes, matched for visual complexity. Pictures were then rated for emotional content. Both control groups rated aversive pictures as much more emotive, and demonstrated in response to these scenes significantly greater activation in regions important for disgust perception, the insula and occipito-temporal cortex, than DP patients (covarying for age, years of education and total extent of brain activation). In DP patients, aversive scenes activated the right ventral prefrontal cortex. The insula was activated only by neutral scenes in this group. Our findings indicate that a core phenomenon of depersonalization--absent subjective experience of emotion--is associated with reduced neural responses in emotion-sensitive regions, and increased responses in regions associated with emotion regulation. [Abstract]

Phillips ML, Sierra M
Depersonalization disorder: a functional neuroanatomical perspective.
Stress. 2003 Sep;6(3):157-65.
Clinical reports of depersonalization suggest that attenuated emotional experience is a central feature of the condition. Patients typically complain of emotional numbness and some patients ascribe their feelings of unreality to a lack of affective "colouring" in things perceived. Recent neuroimaging and psychophysiological studies support these assumptions as they show both attenuated autonomic responses in depersonalization, and decreased activity within neural regions important for the generation of affective responses to emotive stimuli. Furthermore, findings from neuroimaging studies indicate increased prefrontal cortical activity in depersonalised patients, particularly within regions associated with contextualization and appraisal of emotionally-salient information rather than mood induction per se. Taken together, these finding suggest that symptoms of depersonalization, and in particular emotional numbing, may be related to a reversal of normal patterns of autonomic and neural response to emotive stimuli. [Abstract]

Sierra M, Senior C, Dalton J, McDonough M, Bond A, Phillips ML, O'Dwyer AM, David AS
Autonomic response in depersonalization disorder.
Arch Gen Psychiatry. 2002 Sep;59(9):833-8.
BACKGROUND: Emotional-processing inhibition has been suggested as a mechanism underlying some of the clinical features of depersonalization and/or derealization. In this study, we tested the prediction that autonomic response to emotional stimuli would be reduced in patients with depersonalization disorder. METHODS: The skin conductance responses of 15 patients with chronic depersonalization disorder according to DSM-IV, 15 controls, and 11 individuals with anxiety disorders according to DSM-IV, were recorded in response to nonspecific elicitors (an unexpected clap and taking a sigh) and in response to 15 randomized pictures with different emotional valences: 5 unpleasant, 5 pleasant, and 5 neutral. RESULTS: The skin conductance response to unpleasant pictures was significantly reduced in patients with depersonalization disorder (magnitude of 0.017 micro siemens in controls and 0.103 micro siemens in patients with anxiety disorders; P =.01). Also, the latency of response to these stimuli was significantly prolonged in the group with depersonalization disorder (3.01 seconds compared with 2.5 and 2.1 seconds in the control and anxiety groups, respectively; P =.02). In contrast, latency to nonspecific stimuli (clap and sigh) was significantly shorter in the depersonalization and anxiety groups (1.6 seconds) than in controls (2.3 seconds) (P =.03). CONCLUSIONS: In depersonalization disorder, autonomic response to unpleasant stimuli is reduced. The fact that patients with depersonalization disorder respond earlier to a startling noise suggests that they are in a heightened state of alertness and that the reduced response to unpleasant stimuli is caused by a selective inhibitory mechanism on emotional processing. [Abstract]

Simeon D, Guralnik O, Knutelska M, Hollander E, Schmeidler J
Hypothalamic-pituitary-adrenal axis dysregulation in depersonalization disorder.
Neuropsychopharmacology. 2001 Nov;25(5):793-5.
BACKGROUND: The purpose of this preliminary study was to investigate HPA axis function in dissociation. METHODS: Nine subjects with DSM-IV depersonalization disorder (DPD), without lifetime Posttraumatic Stress Disorder (PTSD) or current major depression, were compared to nine healthy comparison (HC) subjects of comparable age and gender. RESULTS: DPD subjects demonstrated significant hyposuppression to low-dose dexamethasone administration and significantly elevated morning plasma cortisol levels when covaried for depression scores, but no difference in 24-hour urinary cortisol excretion. Dissociation scores powerfully predicted suppression whereas depression scores did not contribute to the prediction. CONCLUSIONS: Primary dissociative conditions, such as depersonalization disorder, may be associated with a pattern of HPA axis dysregulation that differs from PTSD and merits further study. [Abstract]

Stanton BR, David AS, Cleare AJ, Sierra M, Lambert MV, Phillips ML, Porter RJ, Gallagher P, Young AH
Basal activity of the hypothalamic-pituitary-adrenal axis in patients with depersonalization disorder.
Psychiatry Res. 2001 Oct 10;104(1):85-9.
Depersonalisation disorder may occur during severe anxiety or following a traumatic event, suggesting a possible role of stress hormones. This study investigated basal activity of the hypothalamic-pituitary-adrenal (HPA) axis in patients with depersonalisation disorder. Salivary cortisol levels were measured at four time points over 12 h in patients with depersonalisation disorder (N=13), major depressive disorder (MDD, N=14) and healthy controls (N=13). Beck Depression Inventory scores were significantly higher in depersonalised subjects than controls, while MDD subjects demonstrated higher scores than both groups. Basal cortisol levels of depersonalised subjects were significantly lower than those of MDD subjects but not healthy controls. These results point to reduced basal activity of the HPA axis in depersonalisation disorder. This pilot study supports the distinction between depersonalisation disorder and major depressive disorder which should be examined in a larger sample. [Abstract]

Simeon D, Guralnik O, Knutelska M, Yehuda R, Schmeidler J
Basal norepinephrine in depersonalization disorder.
Psychiatry Res. 2003 Nov 1;121(1):93-7.
In contrast to the noradrenergic dysregulation described in PTSD, little is known regarding noradrenergic function in dissociative disorders. The purpose of this preliminary study was to investigate basal norepinephrine in depersonalization disorder (DPD). Nine subjects with DSM-IV DPD, without lifetime PTSD, were compared to nine healthy comparison (HC) subjects. Norepinephrine was measured via 24-h urine collection and three serial plasma determinations. Groups did not differ significantly in plasma norepinephrine levels. Compared to the HC group, the DPD group demonstrated significantly higher urinary norepinephrine, only prior to covarying for anxiety. The DPD group also demonstrated a highly significant inverse correlation between urinary norepinephrine and depersonalization severity (r=-0.88). Norepinephrine and cortisol levels (reported in a prior study) were not intercorrelated. We concluded that although dissociation accompanied by anxiety was associated with heightened noradrenergic tone, there was a marked basal norepinephrine decline with increasing severity of dissociation. The findings are in concordance with the few reports on autonomic blunting in dissociation and merit further investigation. [Abstract]

Locatelli M, Bellodi L, Perna G, Scarone S
EEG power modifications in panic disorder during a temporolimbic activation task: relationships with temporal lobe clinical symptomatology.
J Neuropsychiatry Clin Neurosci. 1993 Fall;5(4):409-14.
Computerized EEG activity derived from the temporal lobes was investigated in normal subjects and panic disorder patients with and without depersonalization and/or derealization, in a resting condition and during an odor stimulation task. Panic patients without depersonalization or derealization showed an increase of fast and a decrease of slow activities independent of odor stimulation. Panic patients with depersonalization and/or derealization showed an increase of slow activity and bilateral lack of responsiveness in the fast alpha frequency band during odor stimulation. Findings suggest there are different EEG patterns in the temporal regions of the two different groups of panic patients during rest and activating conditions. [Abstract]

Hunter EC, Phillips ML, Chalder T, Sierra M, David AS
Depersonalisation disorder: a cognitive-behavioural conceptualisation.
Behav Res Ther. 2003 Dec;41(12):1451-67.
Depersonalisation (DP) and derealisation (DR) are subjective experiences of unreality in, respectively, one's sense of self and the outside world. These experiences occur on a continuum from transient episodes that are frequently reported in healthy individuals under certain situational conditions to a chronic psychiatric disorder that causes considerable distress (depersonalisation disorder, DPD). Despite the relatively high rates of reporting these symptoms, little research has been conducted into psychological treatments for this disorder. We suggest that there is compelling evidence to link DPD with the anxiety disorders, particularly panic. This paper proposes that it is the catastrophic appraisal of the normally transient symptoms of DP/DR that results in the development of a chronic disorder. We suggest that if DP/DR symptoms are misinterpreted as indicative of severe mental illness or brain dysfunction, a vicious cycle of increasing anxiety and consequently increased DP/DR symptoms will result. Moreover, cognitive and behavioural responses to symptoms such as specific avoidances, 'safety behaviours' and cognitive biases serve to maintain the disorder by increasing awareness of the symptoms, heightening the perceived threat and preventing disconfirmation of the catastrophic misinterpretations. A coherent model facilitates the development of potentially effective cognitive and behavioural interventions. [Abstract]

Castillo RJ
Depersonalization and meditation.
Psychiatry. 1990 May;53(2):158-68.
From a review of the literature on meditation and depersonalization and interviews conducted with six meditators, this study concludes that: 1) meditation can cause depersonalization and derealization; 2) the meanings in the mind of the meditator regarding the experience of depersonalization will determine to a great extent whether anxiety is present as part of the experience; 3) there need not be any significant anxiety or impairment in social or occupational functioning as a result of depersonalization; 4) a depersonalized state can become an apparently permanent mode of functioning; 5) patients with Depersonalization Disorder may be treated through a process of symbolic healing--that is, changing the meanings associated with depersonalization in the mind of the patient, thereby reducing anxiety and functional impairment; 6) panic/anxiety may be caused by depersonalization if catastrophic interpretations of depersonalization are present. [Abstract]

Grigsby J, Kaye K
Incidence and correlates of depersonalization following head trauma.
Brain Inj. 1993 Nov-Dec;7(6):507-13.
Using the criteria of the Structured Clinical Interview for DSM-III-R Dissociative Disorders (SCID-D), we assessed the incidence of feelings of unreality among a sample of 70 persons who had sustained head injuries. Among those whose head trauma could be classified as mild, more than 60% complained of a depersonalization syndrome. Among those with a significant period of unconsciousness, only 11% had similar complaints. There was a high comorbidity with post-traumatic stress disorder and vertigo. Feelings of unreality were not associated with cognitive impairment or elevated personality test scores, nor were there significant relationships with gender or involvement in litigation. A conservative estimate of incidence of depersonalization among persons with minor head trauma is 13%, while, at the upper end, as many as 67% of persons who sustain mild head injury may experience feelings of unreality. [Abstract]

Noyes R, Hoenk PR, Kuperman S, Slymen DJ
Depersonalization in accident victims and psychiatric patients.
J Nerv Ment Dis. 1977 Jun;164(6):401-7.
A transient depersonalization syndrome was identified in nearly one third of persons exposed to life-threatening danger (accident victims) and close to 40% of a group of hospitalized psychiatric patients. Although the syndrome was similar in these populations, mental clouding developed more commonly among patients and alertness was more prominent among accident victims. Anxiety was significantly associated with the development of depersonalization among psychiatric patients and was almost certainly a factor in its appearance among accident victims. The findings suggest that this syndrome is a specific response to extreme danger or its associated anxiety. [Abstract]

Eriksson NG, Lundin T
Early traumatic stress reactions among Swedish survivors of the m/s Estonia disaster.
Br J Psychiatry. 1996 Dec;169(6):713-6.
BACKGROUND: This study is a three-month follow-up study in order to assess the short-term impact of traumatic stress among 53 Swedish survivors of the Estonia disaster. METHOD: A questionnaire consisting of general questions about conditions during and after the disaster and self-assessment by Post Traumatic Symptom Scale (PTSS-10), Impact of Event Scale (IES), Sense of Coherence-short version (SoC-12), and the DSM-IV list of dissociative symptoms of Acute Stress Disorder formulated as questions regarding individual reactions was distributed. RESULTS: The response rate was 79.2% (n = 42). The participants scored an average of 3.9 on PTSS-10, 28.5 on IES ('intrusion' and 'avoidance' subscales) and 62.8 on SoC-12, which shows elevated levels of post-traumatic stress reactions but a normal level of sense of coherence. The reported occurrence of dissociative symptoms during the disaster was as follows: emotional numbing in 43% of the survivors, reduction of awareness in 55%, derealisation in 67%, depersonalisation in 33%, and dissociative amnesia in 29%. Survivors scoring low in SoC scored significantly higher in both PTSS-10 and IES than those with high scores in SoC. All dissociative symptoms were predictive of post-traumatic reactions. CONCLUSIONS: This study substantiates the importance of assessing dissociative symptoms during a life-threatening event as a possible for later post-traumatic reactions and possible PTSD. The Sense of Coherence Scale may be useful as an instrument to sort out survivors at risk. [Abstract]

Grigsby JP, Johnston CL
Depersonalization, vertigo and Ménière's disease.
Psychol Rep. 1989 Apr;64(2):527-34.
Ménière's disease is generally accepted to be a consequence of distention of the endolymphatic sac of the inner ear. Although the exact etiology is unclear, there is a body of research suggesting that Ménière's disease is of psychosomatic origin. While we do not intend to review the literature exhaustively, we briefly review several frequently cited studies. Even though this literature is so severely flawed that no solid conclusions may be drawn from it, certain questions about the psychological aspect of this disorder continue to surface. Our limited access to patients with vertigo has not allowed us to undertake a carefully designed study. However, in clinical practice we have noted that many persons who complain of vertigo (whether due to Ménière's disease or other causes) also report symptoms of depersonalization and derealization. In this paper we present the cases of two women with Ménière's disease who also experienced concurrent feelings of unreality. It appears likely that feelings of unreality may occur regularly in association with syndromes causing vertigo, presumably as a consequence of vestibular dysfunction. We argue that emotional disturbances previously identified as predisposing causes of Ménière's disease are more likely effects of the disease. Although the discussion of two uncontrolled cases can do little to help solve nagging questions about a psychosomatic component to this disorder, we believe it may suggest a different perspective from which to investigate these complex phenomena. [Abstract]

Nuller YL
Depersonalisation--symptoms, meaning, therapy.
Acta Psychiatr Scand. 1982 Dec;66(6):451-8.
The manifestation of depersonalisation, its relationship with anxiety and depression, as well as its influence on the course of endogenous psychoses were investigated. Forty patients with severe depersonalisation were treated with the benzodiazepine, phenazepam, and 14 with clozapine. The data indicate that depersonalisation results from anxiety; it follows an anxiety attack and is successfully treated with anxiolytic drugs. In the case of endogenous depression, depersonalisation leads to lingering depressive phase, increasing the patients' resistance to antidepressive therapy. The protective and the harmful role of depersonalisation is discussed. [Abstract]

Jiménez-Genchi AM
Repetitive transcranial magnetic stimulation improves depersonalization: a case report.
CNS Spectr. 2004 May;9(5):375-6.
Depersonalization disorder is a poorly understood and treatment-resistant condition. This report describes a patient with depersonalization disorder who underwent six sessions of repetitive transcranial magnetic stimulation on the left dorsolateral prefrontal cortex. Repetitive transcranial magnetic stimulation produced a 28% reduction on depersonalization scores. [Abstract]

Simeon D, Guralnik O, Schmeidler J, Knutelska M
Fluoxetine therapy in depersonalisation disorder: randomised controlled trial.
Br J Psychiatry. 2004 Jul;18531-6.
BACKGROUND: Despite anecdotal reports that serotonin reuptake inhibitors may improve depersonalisation, there is no proven efficacious treatment for depersonalisation disorder. AIMS: To investigate the efficacy of fluoxetine in the treatment of depersonalisation disorder. METHOD: Fifty-four people who met DSM-IV criteria for depersonalisation disorder were recruited through newspaper advertisements, and 50 were randomised to a 10-week, double-blind trial of fluoxetine 10-60 mg/day or placebo. Primary outcome measures were the Dissociative Experiences Scale-Depersonalisation Factor, the Depersonalization Severity Scale and the Clinical Global Impression-Improvement (CGI-I) scale. RESULTS: Intention-to-treat analysis revealed that fluoxetine (mean dosage 48 mg/day) was not superior to placebo except for a clinically minimal but statistically significantly greater improvement in CGI-I score in the fluoxetine group prior to covarying for anxiety and depression (2.9 v. 3.6). Depersonalisation was significantly more likely to improve if comorbid anxiety disorder improved. CONCLUSIONS: Fluoxetine was not efficacious in treating depersonalisation disorder, despite the commonly reported clinical use of serotonin reuptake inhibitors for this condition. [Abstract]

Sierra M, Phillips ML, Ivin G, Krystal J, David AS
A placebo-controlled, cross-over trial of lamotrigine in depersonalization disorder.
J Psychopharmacol. 2003 Mar;17(1):103-5.
There is evidence to support the view that glutamate hyperactivity might be relevant to the neurobiology of depersonalization. We tested the efficacy of lamotrigine, which reduces glutamate release, as a treatment for patients with depersonalization disorder. A double-blind, placebo-controlled, cross-over design was used to evaluate 12 weeks of treatment of lamotrigine. Subjects comprised nine patients with DSM-IV depersonalization disorder. Changes on the Cambridge Depersonalization Scale and the Present State Examination depersonalization/derealization items were compared across the two cross-over periods. Lamotrigine was not significantly superior to placebo. None of the nine patients was deemed a responder to the lamotrigine arm of the cross-over. Lamotrigine does not seem to be useful as a sole medication in the treatment of depersonalization disorder. [Abstract]

Simeon D, Stein DJ, Hollander E
Treatment of depersonalization disorder with clomipramine.
Biol Psychiatry. 1998 Aug 15;44(4):302-3.
BACKGROUND: Although there is a dire paucity of data on the pharmacologic treatment of depersonalization disorder, there have been a few reports in the literature suggesting that selective serotonin reuptake inhibitors may be of therapeutic benefit. In this study, we undertook to evaluate the efficacy of the potent serotonin reuptake inhibitor clomipramine in treating depersonalization. METHODS: Eight subjects with DSM-III-R depersonalization disorder were entered into a double-blind crossover trial consisting of 8 weeks desipramine and 8 weeks clomipramine. Due to the very small size of the trial findings are presented descriptively. RESULTS: Of 7 subjects who entered the clomipramine trial, two showed significant improvement in depersonalization. Three subjects dropped out early, unable to tolerate adverse effects. Of 6 subjects who entered the desipramine trial, I showed significant improvement in depersonalization. One clomipramine responder was subsequently followed in open maintenance treatment with clomipramine for 4 years, and her depersonalization symptoms remained in almost complete remission, with relapses upon each attempt to taper off or switch medication. CONCLUSIONS: Clomipramine may be a promising pharmacologic treatment for primary depersonalization disorder and warrants further investigation. [Abstract]

Abel KM, Allin MP, Kucharska-Pietura K, David A, Andrew C, Williams S, Brammer MJ, Phillips ML
Ketamine alters neural processing of facial emotion recognition in healthy men: an fMRI study.
Neuroreport. 2003 Mar 3;14(3):387-91.
Disruption of facial emotion perception occurs in neuropsychiatric disorders where the expression of emotion is dulled or blunted, for example depersonalization disorder and schizophrenia. It has been suggested that, in the clinical context of emotional blunting, there is a shift in the relative contribution of brain regions subserving cognitive and emotional processing. The non-competitive glutamate receptor antagonist ketamine produces such emotional blunting in healthy subjects. Therefore, we hypothesised that in healthy subjects ketamine would elicit neural responses to emotional stimuli which mimicked those reported in depersonalization disorder and schizophrenia. Thus, we predicted that ketamine would produce reduced activity in limbic and visual brain regions involved in emotion processing, and increased activity in dorsal regions of the prefrontal cortex and cingulate gyrus, both associated with cognitive processing and, putatively, with emotion regulation. Measuring BOLD signal change in fMRI, we examined the neural correlates of ketamine-induced emotional blunting in eight young right-handed healthy men receiving an infusion of ketamine or saline placebo while viewing alternating 30 s blocks of faces displaying fear versus neutral expressions. The normal pattern of neural response occurred in limbic and visual cortex to fearful faces during the placebo infusion. Ketamine abolished this: significant BOLD signal change was demonstrated only in left visual cortex. However, with ketamine, neural responses were demonstrated to neutral expressions in visual cortex, cerebellum and left posterior cingulate gyrus. Emotional blunting may be associated with reduced limbic responses to emotional stimuli and a relative increase in the visual cortical response to neutral stimuli. [Abstract]

Simeon D, Hollander E, Stein DJ, DeCaria C, Cohen LJ, Saoud JB, Isl