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1.
Psychophysiology ; 57(1): e13472, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31502268

RESUMEN

Individuals with post-traumatic stress disorder (PTSD) typically experience states of reliving and hypervigilance; however, the dissociative subtype of PTSD (PTSD+DS) presents with additional symptoms of depersonalization and derealization. Although the insula is critical to emotion processing, its association with these contrasting symptom profiles is yet to be fully delineated. Accordingly, we investigated insula subregion resting-state functional connectivity patterns among individuals with PTSD, PTSD+DS, and healthy controls. Using SPM12 and PRONTO software, we implemented a seed-based resting-state functional connectivity approach, along with multiclass Gaussian process classification machine learning, respectively, in order to evaluate unique patterns and the predictive validity of insula subregion connectivity among individuals with PTSD (n = 84), PTSD+DS (n = 49), and age-matched healthy controls (n = 51). As compared to PTSD and PTSD+DS, healthy controls showed increased right anterior and posterior insula connectivity with frontal lobe structures. By contrast, PTSD showed increased bilateral posterior insula connectivity with subcortical structures, including the periaqueductal gray. Strikingly, as compared to PTSD and controls, PTSD+DS showed increased bilateral anterior and posterior insula connectivity with posterior cortices, including the left lingual gyrus and the left precuneus. Moreover, machine learning analyses were able to classify PTSD, PTSD+DS, and controls using insula subregion connectivity patterns with 80.4% balanced accuracy (p < .01). These findings suggest a neurobiological distinction between PTSD and its dissociative subtype with regard to insula subregion functional connectivity patterns. Furthermore, machine learning algorithms were able to utilize insula resting-state connectivity patterns to discriminate between participant groups with high predictive accuracy.


Asunto(s)
Corteza Cerebral/fisiopatología , Conectoma/normas , Despersonalización/fisiopatología , Trastornos Disociativos/fisiopatología , Aprendizaje Automático , Trastornos por Estrés Postraumático/fisiopatología , Adulto , Corteza Cerebral/diagnóstico por imagen , Despersonalización/diagnóstico por imagen , Despersonalización/etiología , Trastornos Disociativos/diagnóstico por imagen , Trastornos Disociativos/etiología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Trastornos por Estrés Postraumático/complicaciones , Trastornos por Estrés Postraumático/diagnóstico por imagen
2.
Schizophr Bull ; 46(3): 530-539, 2020 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-31784743

RESUMEN

Abnormal space experience (ASE) is a common feature of schizophrenia, despite its absence from current diagnostic manuals. Phenomenological psychopathologists have investigated this experiential disturbance, but these studies were typically based on anecdotal evidence from limited clinical interactions. To better understand the nature of ASE in schizophrenia and attempt to validate previous phenomenological accounts, we conducted a qualitative study of 301 people with schizophrenia. Clinical files were analyzed by means of Consensual Qualitative Research, an inductive method for analyzing descriptions of lived experience. Our main findings can be summed up as follows: (1) ASEs are a relevant feature in schizophrenia (70.1% of patients reported at least 1 ASE). (2) ASE in schizophrenia are characterized by 5 main categories of phenomena (listed from more represented to less represented): (a) experiences of strangeness and unfamiliarity (eg "Everything appeared weird. Face distorted, world looks terrible, nasty"); (b) experiences of centrality/invasion of peripersonal space (eg "Handkerchief on scaffolding: message telling him something"); (c) alteration of the quality of things (eg "Buildings leaning down"); (d) alteration of the quality of the environment (eg "Person sitting six feet away seemed to be at an infinite distance"); and (e) itemization and perceptive salience (eg "All patients [in ward] have bright eyes"). (3) ASEs are much more frequent in acute (91.9%) than in chronic (28.15%) schizophrenia patients. Moreover, our findings further empirical support for phenomenological accounts of schizophrenia, including those developed by Jaspers, Binswanger, Minkowski, and Conrad, among others and provide the background for translational research.


Asunto(s)
Despersonalización/fisiopatología , Trastornos de la Percepción/fisiopatología , Espacio Personal , Esquizofrenia/fisiopatología , Percepción Espacial/fisiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Despersonalización/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastornos de la Percepción/etiología , Investigación Cualitativa , Estudios Retrospectivos , Esquizofrenia/complicaciones , Adulto Joven
3.
Ann Clin Transl Neurol ; 6(9): 1739-1747, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31437864

RESUMEN

OBJECTIVE: Depersonalization refers to the sensation of being detached from one's body, often associated with feelings of loss of control over one's own body, actions, or thoughts. Derealization refers to the altered perception of one's surroundings that is experienced as unreal. Although usually reported by psychiatric patients suffering from depression or anxiety, single case reports and small case series have described depersonalization- and derealization-like symptoms in the context of epilepsy. METHODS: We investigated the brain mechanisms of ictal depersonalization- and derealization like symptoms by analyzing clinical and neuropsychological data as well as the epileptogenic zone based on a multimodal approach in a group of patients reporting depersonalization- (n = 9) and derealization-like symptoms (n = 7), from a single presurgical epilepsy center with focal epilepsy. We compared them with a group of control patients with experiential phenomena due to temporal lobe epilepsy (n = 28). RESULTS: We show that all patients with ictal depersonalization-like symptoms report altered self-identification with their body and mostly suffer from frontal lobe epilepsy with the epileptogenic zone in the dorsal premotor cortex, while patients with derealization-like symptoms suffer from temporal lobe epilepsy. This finding is supported by post-ictal neuropsychological deficits, showing that depersonalization-like symptoms were significantly more often associated with frontal lobe dysfunction as compared to the control patients and patients with derealization-like symptoms. CONCLUSION: We argue that depersonalization of epileptic origin constitutes a distinct disorder due to frontal lobe epilepsy. We discuss these findings with respect to earlier accounts of depersonalization and the recent concept of bodily self-consciousness.


Asunto(s)
Encéfalo/fisiopatología , Despersonalización/complicaciones , Epilepsia/complicaciones , Adulto , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Despersonalización/diagnóstico por imagen , Despersonalización/fisiopatología , Electroencefalografía , Epilepsia/diagnóstico por imagen , Epilepsia/fisiopatología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Pruebas Neuropsicológicas , Estudios Retrospectivos
4.
J Pers ; 87(2): 295-309, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-29626343

RESUMEN

OBJECTIVE: Dissociation refers to a disintegration between psychological elements; common manifestations are embodied in "absorption and imaginative involvement," a propensity for being immersed in a stimulus while oblivious to the environment, and acting without awareness. Trait dissociation was hypothesized to relate to lower EEG signal connectivity, but studies on healthy populations are scarce. The present study set out to examine whether dissociative absorption in a nonclinical sample would be associated with decreased intrahemispheric coherence. METHOD: In 84 healthy Israeli soldiers (49% females; Mage = 22.24, SD = 2.64), resting-state electroencephalography (rsEEG) was recorded for a period of 3 min with eyes closed and 3 min with eyes open. RESULTS: Decreased coherence was related to high dissociative absorption in the long (frontal-occipital) range, and in one of the pairs of the short range (central-parietal). The effects emerged mostly in the left hemisphere, in both eyes-open and eyes-closed conditions, and for a range of spectral bands, although long-range effects were more pronounced in slow-wave bands (theta and delta). CONCLUSIONS: Dissociative absorption is manifested in segregated cortical activity, supporting the notion that it may represent less integrated mental functioning. The findings contribute to our understanding of the neural correlates of consciousness and personality.


Asunto(s)
Concienciación/fisiología , Corteza Cerebral/fisiología , Electroencefalografía , Personalidad/fisiología , Adulto , Amnesia/fisiopatología , Despersonalización/fisiopatología , Trastornos Disociativos/fisiopatología , Femenino , Lateralidad Funcional/fisiología , Humanos , Masculino , Adulto Joven
6.
Rev Neurol ; 67(5): 187-191, 2018 Sep 01.
Artículo en Español | MEDLINE | ID: mdl-30047121

RESUMEN

INTRODUCTION: The use of medical metaphors is common in the social discourse and in the media. However, the use by physicians themselves to define different concepts to the original meaning of the medical word is rare. AIM: To analyze the term «scotoma¼ in its metaphorical sense in the works of the neurologist and writer Oliver Sacks. DEVELOPMENT: Sacks used scotoma metaphorically in two works, in the autobiographical book A leg to stand on and in an essay Scotoma: forgetting and neglect in science. In the first case, he used it to define the sensorial loss of his leg after an accident, which could be interpreted as a «mental scotoma¼. In the second case, Sacks analyzed the process and the reasons of forgetting the works of some early scientific discoverers and discussed why this happened. In this case, Sacks made an analogy with the process suffered by scientific discoveries and the reasons why some of them are largely ignored, in a situation that he called «historical¼ or «social scotoma¼. CONCLUSIONS: Sacks does not use the term «scotoma¼ uniformly. When used to describe the sensorial loss of his leg, it might be considered that scotoma is there a second, although minor but accepted, meaning of the word. However, its use in the definition of historical neglect of early discoveries can be clearly defined as a medical metaphor in full sense.


TITLE: Los escotomas como metafora en la obra de Oliver Sacks.Introduccion. La utilizacion de metaforas medicas es frecuente en el discurso social y en los medios de comunicacion. Sin embargo, su empleo por los propios medicos para definir conceptos distintos al significado original del termino resulta poco habitual. Objetivo. Analizar el empleo del termino «escotoma¼, en su sentido metaforico, en las obras del neurologo y escritor Oliver Sacks. Desarrollo. Sacks uso escotoma metaforicamente en dos obras, en el libro autobiografico A leg to stand on y en un ensayo, Scotoma: forgetting and neglect in science. En el primer caso, lo utilizo para describir la situacion de perdida sensorial de su extremidad inferior, que experimento despues de un accidente, lo que podria interpretarse como un «escotoma mental¼. En el segundo caso, Sacks analizo el proceso y las razones del olvido de las obras de algunos descubridores cientificos precoces y comento por que habia sucedido, una situacion que denomino «escotoma historico¼ o «social¼. Conclusiones. Sacks no utiliza el termino «escotoma¼ de forma uniforme y, si bien en el caso de su accidente podria considerarse como una acepcion menor, pero aceptada, es indudable su uso como metafora medica para describir el olvido y la ignorancia de algunos descubrimientos cientificos en determinadas situaciones historicas.


Asunto(s)
Literatura Moderna , Medicina en la Literatura , Metáfora , Neurología/historia , Escotoma/psicología , Despersonalización/fisiopatología , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Pierna/inervación , Traumatismos de la Pierna/fisiopatología , Traumatismos de la Pierna/psicología , Londres , Los Angeles , Memoria , New York , Trastornos de la Percepción/fisiopatología
7.
Conscious Cogn ; 63: 29-46, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29929064

RESUMEN

Depersonalization and Derealization are characterised by feelings of detachment from one's bodily self/surroundings and a general emotional numbness. We explored predisposition to trait-based experiences of depersonalization/derealization-type experiences and autonomic arousal toward simulated body-threats, which were delivered to the participant's own body (i.e. Self) and when observed being delivered to another individual (i.e. Other). Ninety participants took part in an "Implied Body-Threat Illusion" task (Dewe, Watson, & Braithwaite, 2016) and autonomic arousal was recorded via standardised skin conductance responses and finger temperature. Autonomic suppression in response to threats delivered to the Self correlated with increases in trait-based depersonalization-type experiences. In contrast, autonomic suppression for threats delivered to Others correlated with trait-based derealization-like experiences. Body-temperature and anticipatory arousal did not correlate reliably with predisposition to depersonalization- or derealization-type experiences. The theoretical implications of these findings are discussed in terms of a fronto-limbic autonomic suppression mechanism.


Asunto(s)
Encéfalo/fisiopatología , Estado de Conciencia/fisiología , Despersonalización/fisiopatología , Respuesta Galvánica de la Piel/fisiología , Adolescente , Adulto , Nivel de Alerta , Temperatura Corporal/fisiología , Miedo/fisiología , Miedo/psicología , Femenino , Dedos , Humanos , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Adulto Joven
8.
Psychiatr Danub ; 30(1): 21-25, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29546854

RESUMEN

French expression standing for the phrase "already seen" is a déjà vu. It is thought that as much as 97% of the population have experienced déjà vu at least once in their lifetime and 67% experience it regularly. The explanations of this phenomenon in novels and poems include reincarnation, dreams, organic factors, and unconscious memories. In this narrative review connection between déjà vu and various other conditions has been mentioned: false memories, temporal lobe epilepsy and other neurological conditions. In psychiatric patients déjà vu phenomenon is more often seen in patients with anxiety and people with derealisation/ depersonalization. It seems that temporal region is the origin of déjà vu phenomena in both healthy individuals and in individuals with neurological and psychiatric conditions, but the exact mechanism of this phenomenon is however still unknown. More attention should also be given to déjà vu from philosophical and religious perspectives as well. Déjà vu is still an enigma which could only be revealed with multidisciplinary approach through cooperation between neurologists, brain scientists, psychiatrists and experimental psychologists.


Asunto(s)
Déjà Vu/psicología , Adulto , Encéfalo/fisiopatología , Despersonalización/fisiopatología , Despersonalización/psicología , Epilepsia del Lóbulo Temporal/fisiopatología , Epilepsia del Lóbulo Temporal/psicología , Humanos , Comunicación Interdisciplinaria , Colaboración Intersectorial , Masculino , Trastornos Neurocognitivos/fisiopatología , Trastornos Neurocognitivos/psicología , Represión Psicológica
9.
Schizophr Bull ; 44(4): 720-727, 2018 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-29529266

RESUMEN

The self-disorder model offers a unifying way of conceptualizing schizophrenia's highly diverse symptoms (positive, negative, disorganized), of capturing their distinctive bizarreness, and of conceiving their longitudinal development. These symptoms are viewed as differing manifestations of an underlying disorder of ipseity or core-self: hyper-reflexivity/diminished-self-presence with accompanying disturbances of "grip" or "hold" on reality. Recent revision to this phenomenological theory, in particular distinguishing primary-vs-secondary factors, offers a bio-pheno-social model that is consistent with recent empirical findings and offers several advantages: (1) It helps account for the temporal variations of the symptoms or syndrome, including longitudinal progression, but also the shorter-term, situationally reactive, and sometimes defensive or quasi-intentional variability of symptom-expression that can occur in schizophrenia (consistent with understanding some aspects of ipseity-disturbance as dynamic and mutable, involving shifting attitudes or experiential orientations). (2) It accommodates the overlapping of some key schizophrenic symptoms with certain nonschizophrenic conditions involving dissociation (depersonalization, derealization), including depersonalization disorder and panic disorder, thereby acknowledging both shared and distinguishing symptoms. (3) It integrates recent neurocognitive and neurobiological as well as psychosocial (eg, influence of trauma and culture) findings into a coherent but multi-factorial neuropsychological account. An adequate model of schizophrenia will postulate shared disturbances of core-self experiences that nevertheless can follow several distinct pathways and occur in various forms. Such a model is preferable to uni-dimensional alternatives-whether of schizophrenia or ipseity-disturbance-given its ability to account for distinctive yet varying experiential and neurocognitive abnormalities found in research on schizophrenia, and to integrate these with recent psychosocial and neurobiological findings.


Asunto(s)
Despersonalización/fisiopatología , Ego , Modelos Teóricos , Esquizofrenia/fisiopatología , Humanos
10.
Schizophr Bull ; 44(suppl_2): S501-S511, 2018 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-29566227

RESUMEN

The mirror-gazing task (MGT) experimentally induces illusions, ranging from simple color changes in the specular image of oneself, to depersonalization-like anomalous self-experiences (ASE) as in experiencing one's specular image as someone else. The objective was to characterize how connectivity in resting-state networks (RSNs) differed in adolescents reporting such depersonalization-like ASEs during the MGT, in a cross-sectional (Y1) and in a longitudinal manner (a year after). 75 adolescents were recruited; for the cross-sectional analysis, participants were split into 2 groups: those who reported depersonalization-like ASEs on the MGT (ASE), and those who did not (NoASE). For the longitudinal analysis, participants were split into 3 groups whether they experienced MGT depersonalization-like ASEs: only at Y1 (Remitters), both times (Persisters), or never (Controls). Participants also filled out self-reports assessing schizotypal personality (Schizotypal Personality Questionnaire [SPQ]), and underwent resting-state functional MRI procedure (rs-fMRI). A group level Independent Component Analysis (ICA) was conducted and voxel-wise inter-group differences within RSNs were examined. The rs-fMRI analysis revealed lower connectivity of specific visual areas within the primary visual network (PVN), and higher connectivity of regions within the Default Mode Network (DMN) when contrasting the ASE and NoASE groups. The areas that were atypically connected within the PVN further presented differential pattern of connectivity in the longitudinal analysis. Atypical connectivity of visual area within the DMN at Y1 was associated with higher scores on the disorganized dimension of schizotypy at the second evaluation. The present study uncovers a subtle signature in the RSNs of non-clinical adolescents who experienced task-induced ASEs.


Asunto(s)
Mapeo Encefálico/métodos , Corteza Cerebral/fisiopatología , Despersonalización/fisiopatología , Ilusiones/fisiología , Red Nerviosa/fisiopatología , Percepción Visual/fisiología , Adolescente , Adulto , Corteza Cerebral/diagnóstico por imagen , Niño , Estudios Transversales , Despersonalización/diagnóstico por imagen , Femenino , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Red Nerviosa/diagnóstico por imagen , Adulto Joven
11.
Biol Psychol ; 134: 64-71, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29486234

RESUMEN

Depersonalisation (DP) is a psychological condition marked by feelings of disembodiment. In everyday life, it is frequently associated with concentration problems. The present study used visual event-related potentials (ERPs) in a Posner-type spatial cueing task with valid, invalid and spatially neutral cues to delineate the potential neurophysiological correlates of these concentration problems. Altered attentional functioning at early, sensory stages was found in DP patients but not in anxiety- and depression-matched psychosomatic patients without DP. Specifically, DP was associated with decreased suppression of stimuli at unattended locations, shown as absent processing costs for invalidly versus neutrally cued stimuli over P1 (135-150 ms). Attentional benefits at N1, and all attentional effects at later, cognitive processing stages (P2-N2, P3) were similar in both groups. We propose that this insufficient early suppression of unattended stimuli may result from atypical sensory gain control in DP.


Asunto(s)
Atención , Despersonalización/fisiopatología , Despersonalización/psicología , Potenciales Evocados , Adulto , Cognición , Señales (Psicología) , Electroencefalografía , Femenino , Humanos , Masculino , Escalas de Valoración Psiquiátrica , Desempeño Psicomotor , Trastornos Psicofisiológicos/fisiopatología , Trastornos Psicofisiológicos/psicología , Tiempo de Reacción , Percepción Espacial
12.
Perception ; 47(2): 197-215, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29161965

RESUMEN

The experience of seeing one's own face in a mirror is a common experience in daily life. Visual feedback from a mirror is linked to a sense of identity. We developed a procedure that allowed individuals to watch their own face, as in a normal mirror, or with specific distortions (lag) for active movement or passive touch. By distorting visual feedback while the face is being observed on a screen, we document an illusion of reduced embodiment. Participants made mouth movements, while their forehead was touched with a pen. Visual feedback was either synchronous (simultaneous) with reality, as in a mirror, or asynchronous (delayed). Asynchronous feedback was exclusive to touch or movement in different conditions and incorporated both in a third condition. Following stimulation, participants rated their perception of the face in the mirror, and perception of their own face, on questions that tapped into agency and ownership. Results showed that perceptions of both agency and ownership were affected by asynchrony. Effects related to agency, in particular, were moderated by individual differences in depersonalisation and auditory hallucination-proneness, variables with theoretical links to embodiment. The illusion presents a new way of investigating the extent to which body representations are malleable.


Asunto(s)
Despersonalización/fisiopatología , Reconocimiento Facial/fisiología , Retroalimentación Sensorial/fisiología , Alucinaciones/fisiopatología , Ilusiones/fisiología , Autoimagen , Percepción del Tacto/fisiología , Adulto , Femenino , Humanos , Masculino , Factores de Tiempo , Adulto Joven
13.
Psychiatry ; 80(3): 265-278, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29087250

RESUMEN

OBJECTIVE: Dissociative experiences are associated with several psychopathological symptoms and are a hindrance to therapeutic gain. Depersonalization-derealization (DEP-DER) is positively associated with stress and anxiety, while absorption and imaginative involvement (ABS), a tendency for total, immersed attention, is commonly referred to as nonpathological dissociation, although it is positively associated with obsessive-compulsive (OC) symptoms. Previous studies in the field have been mainly cross-sectional. The present study aimed to examine these associations rigorously and attempted to determine directionality between dissociation and distress. METHOD: The current study employed both variable-centered (cross-sectional) and person-centered (longitudinal, within-subjects) analyses of the associations of DEP-DER and ABS with distress. Undergraduate students (N = 184) completed trait questionnaires on dissociation, stress, anxiety, depression, and OC symptoms, and n = 78 also completed questionnaires assessing the same constructs daily for 14 days. Multiple regression and multilevel modeling analyses were conducted. RESULTS: In the cross-sectional phase, DEP-DER was uniquely positively related to anxiety and OC symptoms, and ABS was uniquely positively related to OC symptoms. In the daily diary phase, increases in DEP-DER were related to increases in anxiety, depression, OC symptoms, and stress, while increases in ABS were related to increases in OC symptoms and stress. In addition, time-lag analysis showed that ABS tended to temporally precede OC. CONCLUSIONS: ABS foretold increases in OC symptoms, at least in this nonclinical sample. Future studies on clinical samples should explore whether ABS should be referred to as "nonpathological" and its possible role in the development or maintenance of clinical-level OCD.


Asunto(s)
Ansiedad/fisiopatología , Despersonalización/fisiopatología , Depresión/fisiopatología , Trastornos Disociativos/fisiopatología , Trastorno Obsesivo Compulsivo/fisiopatología , Estrés Psicológico/fisiopatología , Adulto , Ansiedad/epidemiología , Comorbilidad , Estudios Transversales , Despersonalización/epidemiología , Depresión/epidemiología , Trastornos Disociativos/epidemiología , Femenino , Humanos , Estudios Longitudinales , Masculino , Trastorno Obsesivo Compulsivo/epidemiología , Estrés Psicológico/epidemiología , Adulto Joven
14.
J Exp Psychol Hum Percept Perform ; 43(6): 1125-1143, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28263626

RESUMEN

It has been argued that disorders in body-ownership and aberrant experiences in self-consciousness are due to biases in multisensory integration. Here we examine whether such biases are also associated with spontaneous out-of-body experiences (OBEs) in a nonclinical population. One-hundred and 80 participants took part in a rubber hand illusion (RHI) experiment with synchronous and asynchronous visual and tactile stimulation. A realistic threat was delivered to the rubber hand after a fixed period of stimulation. Self-report exit questionnaires measured the subjective strength of the illusion and psychophysiological measures (skin conductance responses/finger temperature) provided an objective index of fear/anxiety toward the threat. Control participants reported a stronger RHI, and revealed larger threat-related skin conductance responses during synchronous compared with asynchronous brushing. For participants predisposed to OBEs, the magnitude of the skin conductance was not influenced by brushing synchrony-fear responses were just as strong in the asynchronous condition as they were in the synchronous condition. There were also no reliable effects of finger temperature for either group. Collectively, these findings are taken as support for the presence of particular biases in multisensory integration (perhaps via predictive coding mechanisms) in which imprecise top-down tuning occurs resulting in aberrant experiences in self-consciousness even in nonclinical hallucinators. (PsycINFO Database Record


Asunto(s)
Despersonalización/fisiopatología , Respuesta Galvánica de la Piel/fisiología , Alucinaciones/fisiopatología , Ilusiones/fisiología , Temperatura Cutánea/fisiología , Percepción del Tacto/fisiología , Percepción Visual/fisiología , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
15.
Curr Psychiatry Rep ; 19(1): 6, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28138924

RESUMEN

Dissociation involves disruptions of usually integrated functions of consciousness, perception, memory, identity, and affect (e.g., depersonalization, derealization, numbing, amnesia, and analgesia). While the precise neurobiological underpinnings of dissociation remain elusive, neuroimaging studies in disorders, characterized by high dissociation (e.g., depersonalization/derealization disorder (DDD), dissociative identity disorder (DID), dissociative subtype of posttraumatic stress disorder (D-PTSD)), have provided valuable insight into brain alterations possibly underlying dissociation. Neuroimaging studies in borderline personality disorder (BPD), investigating links between altered brain function/structure and dissociation, are still relatively rare. In this article, we provide an overview of neurobiological models of dissociation, primarily based on research in DDD, DID, and D-PTSD. Based on this background, we review recent neuroimaging studies on associations between dissociation and altered brain function and structure in BPD. These studies are discussed in the context of earlier findings regarding methodological differences and limitations and concerning possible implications for future research and the clinical setting.


Asunto(s)
Trastorno de Personalidad Limítrofe/diagnóstico por imagen , Trastorno de Personalidad Limítrofe/fisiopatología , Encéfalo/fisiopatología , Despersonalización/diagnóstico por imagen , Despersonalización/fisiopatología , Trastornos Disociativos/diagnóstico por imagen , Trastornos Disociativos/fisiopatología , Trastornos por Estrés Postraumático/diagnóstico por imagen , Trastornos por Estrés Postraumático/fisiopatología , Trastorno de Personalidad Limítrofe/psicología , Mapeo Encefálico , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/fisiopatología , Despersonalización/psicología , Trastornos Disociativos/psicología , Humanos , Sistema Límbico/diagnóstico por imagen , Sistema Límbico/fisiopatología , Neuroimagen , Trastornos por Estrés Postraumático/psicología
16.
Psychiatry Res ; 240: 4-10, 2016 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-27078753

RESUMEN

Patients with depersonalization-/derealization disorder (DPD) show altered heartbeat-evoked brain potentials, which are considered psychophysiological indicators of cortical representation of visceral-afferent neural signals. The aim of the current investigation was to clarify whether the impaired CNS representation of visceral-afferent neural signals in DPD is restricted to the cortical level or is also present in sub-cortical structures. We used cardiac modulation of startle (CMS) to assess baro-afferent signal transmission at brainstem level in 22 DPD and 23 healthy control individuals. The CMS paradigm involved acoustic startle stimuli (105dB(A), 50ms) elicited 0, 100, 200, 300, 400 and 500ms after a cardiac R-wave. In healthy control individuals, we observed lower startle responses at 100 and 300ms than at 0 and 400ms after an R-wave. In DPD patients, no effect of the cardiac cycle on startle response magnitude was found. We conclude that the representation of visceral-afferent neural signals at brainstem level may be deficient in DPD. This effect may be due to increased peripheral sympathetic tone or to dysregulated signal processing at brainstem level.


Asunto(s)
Barorreflejo/fisiología , Tronco Encefálico/fisiopatología , Despersonalización/fisiopatología , Reflejo de Sobresalto/fisiología , Aferentes Viscerales/fisiopatología , Estimulación Acústica , Adulto , Encéfalo/fisiopatología , Potenciales Evocados/fisiología , Femenino , Corazón/fisiopatología , Frecuencia Cardíaca/fisiología , Humanos , Masculino
17.
Psychol Trauma ; 8(5): 592-600, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27100173

RESUMEN

OBJECTIVE: The inclusion of a dissociative subtype in the Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM­5) criteria for the diagnosis of posttraumatic stress disorder (PTSD) has highlighted the need for valid and reliable measures of dissociative symptoms across developmental periods. The Adolescent Dissociative Experiences Scale (A-DES) is 1 of the few measures validated for young persons, but previous studies have yielded inconsistent results regarding its factor structure. Further, research to date on the A-DES has been based upon nonclinical samples of youth or those without a known history of trauma. To address these gaps in the literature, the present study investigated the factor structure and construct validity of the A-DES in a sample of highly trauma-exposed youth involved in the juvenile justice system. METHOD: A sample of 784 youth (73.7% boys) recruited from a detention center completed self-report measures of trauma exposure and the A-DES, a subset of whom (n = 212) also completed a measure of PTSD symptoms. RESULTS: Confirmatory factor analyses revealed a best fitting 3-factor structure comprised of depersonalization or derealization, amnesia, and loss of conscious control, with configural and metric invariance across gender. Logistic regression analyses indicated that the depersonalization or derealization factor effectively distinguished between those youth who did and did not likely meet criteria for a diagnosis of PTSD as well as those with PTSD who did and did not likely meet criteria for the dissociative subtype. CONCLUSIONS: These results provide support for the multidimensionality of the construct of posttraumatic dissociation and contribute to the understanding of the dissociative subtype of PTSD among adolescents. (PsycINFO Database Record


Asunto(s)
Conducta del Adolescente/psicología , Despersonalización/fisiopatología , Trastornos Disociativos/fisiopatología , Delincuencia Juvenil/psicología , Escalas de Valoración Psiquiátrica/normas , Trauma Psicológico/fisiopatología , Trastornos por Estrés Postraumático/fisiopatología , Adolescente , Trastornos Disociativos/diagnóstico , Femenino , Humanos , Masculino
18.
Psychiatry Res ; 240: 118-122, 2016 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-27104926

RESUMEN

Case reports and an open trial have reported promising responses to repetitive transcranial magnetic stimulation (rTMS) to prefrontal and temporo-parietal sites in patients with depersonalization disorder (DPD). We recently showed that a single session of rTMS to the ventrolateral prefrontal cortex (VLPFC) was associated with a reduction in symptoms and increase in physiological arousal. Seven patients with medication-resistant DSM-IV DPD received up to 20 sessions of right-sided rTMS to the VLPFC for 10 weeks. Stimulation was guided using neuronavigation software based on participants' individual structural MRIs, and delivered at 110% of resting motor threshold. A session consisted of 1Hz repetitive TMS for 15min. The primary outcome measure was reduction in depersonalization symptoms on the Cambridge Depersonalization Scale (CDS). Secondary outcomes included scores on the Beck Depression Inventory (BDI) and Beck Anxiety Inventory (BAI). 20 sessions of rTMS treatment to right VLPFC significantly reduced scores on the CDS by on average 44% (range 2-83.5%). Two patients could be classified as "full responders", four as "partial" and one a non-responder. Response usually occurred within the first 6 sessions. There were no significant adverse events. A randomized controlled clinical trial of VLPFC rTMS for DPD is warranted.


Asunto(s)
Despersonalización/terapia , Corteza Prefrontal/fisiopatología , Estimulación Magnética Transcraneal/métodos , Adulto , Despersonalización/fisiopatología , Femenino , Humanos , Londres , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Proyectos de Investigación , Resultado del Tratamiento
19.
Soc Cogn Affect Neurosci ; 11(6): 945-51, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26940563

RESUMEN

The mechanism by which the brain integrates visual and emotional information remains incompletely understood, and can be studied through focal lesions that selectively disrupt this process. To date, three reported cases of visual hypoemotionality, a vision-specific form of derealization, have resulted from lesions of the temporo-occipital junction. We present a fourth case of this rare phenomenon, and investigate the role of the inferior longitudinal fasciculus (ILF) in the underlying pathophysiology. A 50-year-old right-handed male was found to have a right medial temporal lobe tumor following new-onset seizures. Interstitial laser ablation of the lesion was complicated by a right temporo-parieto-occipital intraparenchymal hemorrhage. The patient subsequently experienced emotional estrangement from visual stimuli. A lesion overlap analysis was conducted to assess involvement of the ILF by this patient's lesion and those of the three previously described cases, and diffusion tensor imaging was acquired in our case to further investigate ILF disruption. All four lesions specifically overlapped with the expected trajectory of the right ILF, and diminished structural integrity of the right ILF was observed in our case. These findings implicate the ILF in visual hypoemotionality, suggesting that the ILF is critical for integrating visual information with its emotional content.


Asunto(s)
Neoplasias Encefálicas/complicaciones , Corteza Cerebral , Hemorragia Cerebral/complicaciones , Trastornos Disociativos/fisiopatología , Emociones/fisiología , Neoplasias Neuroepiteliales/complicaciones , Convulsiones/fisiopatología , Corteza Cerebral/patología , Corteza Cerebral/fisiopatología , Despersonalización/etiología , Despersonalización/fisiopatología , Imagen de Difusión Tensora , Trastornos Disociativos/etiología , Humanos , Masculino , Persona de Mediana Edad , Vías Nerviosas/patología , Vías Nerviosas/fisiopatología , Convulsiones/etiología
20.
Eur J Neurosci ; 43(7): 971-8, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26791018

RESUMEN

Previous studies have yielded evidence for cognitive processing abnormalities and alterations of autonomic functioning in depersonalization-derealization disorder (DPRD). However, multimodal neuroimaging and psychophysiology studies have not yet been conducted to test for functional and effective connectivity under cognitive stress in patients with DPRD. DPRD and non-referred control subjects underwent a combined Stroop/negative priming task, and the neural correlates of Stroop interference effect, negative priming effect, error rates, cognitive load span and average amplitude of skin conductance responses were ascertained for both groups. Evoked haemodynamic responses for basic Stroop/negative priming activations were compared. For basic Stroop to neutral contrast, patients with DPRD differed in the location (inferior vs. superior lobule) of the parietal region involved, but showed similar activations in the left frontal region. In addition, patients with DPRD also co-activated the dorsomedial prefrontal cortex (BA9) and posterior cingulate cortex (BA31), which were also found to be the main between-group difference regions. These regions furthermore showed connectivity with frequency of depersonalization states. Evoked haemodynamic responses drawn from regions of interest indicated significant between-group differences in 30-40% of time points. Brain-behaviour correlations differed mainly in laterality, yet only slightly in regions. A reversal of autonomic patterning became evident in patients with DPRD for cognitive load spans, indicating less effective arousal suppression under cognitive stress - patients with DPRD showed positive associations of cognitive load with autonomic responses, whereas controls exhibit respective inverse association. Overall, the results of the present study show only minor executive cognitive peculiarities, but further support the notion of abnormalities in autonomic functioning in patients with DPRD.


Asunto(s)
Nivel de Alerta , Cognición , Despersonalización/fisiopatología , Respuesta Galvánica de la Piel , Adulto , Asociación , Sistema Nervioso Autónomo/fisiopatología , Estudios de Casos y Controles , Función Ejecutiva , Femenino , Lóbulo Frontal/fisiopatología , Humanos , Sistema Límbico/fisiopatología , Masculino , Test de Stroop
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