Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 88
Filtrar
1.
Psychophysiology ; 57(1): e13472, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31502268

RESUMO

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.


Assuntos
Córtex Cerebral/fisiopatologia , Conectoma/normas , Despersonalização/fisiopatologia , Transtornos Dissociativos/fisiopatologia , Aprendizado de Máquina , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adulto , Córtex Cerebral/diagnóstico por imagem , Despersonalização/diagnóstico por imagem , Despersonalização/etiologia , Transtornos Dissociativos/diagnóstico por imagem , Transtornos Dissociativos/etiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Transtornos de Estresse Pós-Traumáticos/complicações , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem
2.
Schizophr Bull ; 46(3): 530-539, 2020 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-31784743

RESUMO

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.


Assuntos
Despersonalização/fisiopatologia , Transtornos da Percepção/fisiopatologia , Espaço Pessoal , Esquizofrenia/fisiopatologia , Percepção Espacial/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Despersonalização/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos da Percepção/etiologia , Pesquisa Qualitativa , Estudos Retrospectivos , Esquizofrenia/complicações , Adulto Jovem
3.
Ann Clin Transl Neurol ; 6(9): 1739-1747, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31437864

RESUMO

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.


Assuntos
Encéfalo/fisiopatologia , Despersonalização/complicações , Epilepsia/complicações , Adulto , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Despersonalização/diagnóstico por imagem , Despersonalização/fisiopatologia , Eletroencefalografia , Epilepsia/diagnóstico por imagem , Epilepsia/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Estudos Retrospectivos
4.
J Pers ; 87(2): 295-309, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-29626343

RESUMO

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.


Assuntos
Conscientização/fisiologia , Córtex Cerebral/fisiologia , Eletroencefalografia , Personalidade/fisiologia , Adulto , Amnésia/fisiopatologia , Despersonalização/fisiopatologia , Transtornos Dissociativos/fisiopatologia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino , Adulto Jovem
6.
Rev Neurol ; 67(5): 187-191, 2018 Sep 01.
Artigo em Espanhol | MEDLINE | ID: mdl-30047121

RESUMO

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.


Assuntos
Literatura Moderna , Medicina na Literatura , Metáfora , Neurologia/história , Escotoma/psicologia , Despersonalização/fisiopatologia , História do Século XX , História do Século XXI , Humanos , Perna (Membro)/inervação , Traumatismos da Perna/fisiopatologia , Traumatismos da Perna/psicologia , Londres , Los Angeles , Memória , New York , Transtornos da Percepção/fisiopatologia
7.
Conscious Cogn ; 63: 29-46, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29929064

RESUMO

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.


Assuntos
Encéfalo/fisiopatologia , Estado de Consciência/fisiologia , Despersonalização/fisiopatologia , Resposta Galvânica da Pele/fisiologia , Adolescente , Adulto , Nível de Alerta , Temperatura Corporal/fisiologia , Medo/fisiologia , Medo/psicologia , Feminino , Dedos , Humanos , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Adulto Jovem
8.
Schizophr Bull ; 44(suppl_2): S501-S511, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-29566227

RESUMO

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.


Assuntos
Mapeamento Encefálico/métodos , Córtex Cerebral/fisiopatologia , Despersonalização/fisiopatologia , Ilusões/fisiologia , Rede Nervosa/fisiopatologia , Percepção Visual/fisiologia , Adolescente , Adulto , Córtex Cerebral/diagnóstico por imagem , Criança , Estudos Transversais , Despersonalização/diagnóstico por imagem , Feminino , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Adulto Jovem
9.
Psychiatr Danub ; 30(1): 21-25, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29546854

RESUMO

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.


Assuntos
Déjà Vu/psicologia , Adulto , Encéfalo/fisiopatologia , Despersonalização/fisiopatologia , Despersonalização/psicologia , Epilepsia do Lobo Temporal/fisiopatologia , Epilepsia do Lobo Temporal/psicologia , Humanos , Comunicação Interdisciplinar , Colaboração Intersetorial , Masculino , Transtornos Neurocognitivos/fisiopatologia , Transtornos Neurocognitivos/psicologia , Repressão Psicológica
10.
Schizophr Bull ; 44(4): 720-727, 2018 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-29529266

RESUMO

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.


Assuntos
Despersonalização/fisiopatologia , Ego , Modelos Teóricos , Esquizofrenia/fisiopatologia , Humanos
11.
Biol Psychol ; 134: 64-71, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29486234

RESUMO

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.


Assuntos
Atenção , Despersonalização/fisiopatologia , Despersonalização/psicologia , Potenciais Evocados , Adulto , Cognição , Sinais (Psicologia) , Eletroencefalografia , Feminino , Humanos , Masculino , Escalas de Graduação Psiquiátrica , Desempenho Psicomotor , Transtornos Psicofisiológicos/fisiopatologia , Transtornos Psicofisiológicos/psicologia , Tempo de Reação , Percepção Espacial
12.
Perception ; 47(2): 197-215, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29161965

RESUMO

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.


Assuntos
Despersonalização/fisiopatologia , Reconhecimento Facial/fisiologia , Retroalimentação Sensorial/fisiologia , Alucinações/fisiopatologia , Ilusões/fisiologia , Autoimagem , Percepção do Tato/fisiologia , Adulto , Feminino , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
13.
Psychiatry ; 80(3): 265-278, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29087250

RESUMO

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.


Assuntos
Ansiedade/fisiopatologia , Despersonalização/fisiopatologia , Depressão/fisiopatologia , Transtornos Dissociativos/fisiopatologia , Transtorno Obsessivo-Compulsivo/fisiopatologia , Estresse Psicológico/fisiopatologia , Adulto , Ansiedade/epidemiologia , Comorbidade , Estudos Transversais , Despersonalização/epidemiologia , Depressão/epidemiologia , Transtornos Dissociativos/epidemiologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Transtorno Obsessivo-Compulsivo/epidemiologia , Estresse Psicológico/epidemiologia , Adulto Jovem
14.
J Exp Psychol Hum Percept Perform ; 43(6): 1125-1143, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28263626

RESUMO

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


Assuntos
Despersonalização/fisiopatologia , Resposta Galvânica da Pele/fisiologia , Alucinações/fisiopatologia , Ilusões/fisiologia , Temperatura Cutânea/fisiologia , Percepção do Tato/fisiologia , Percepção Visual/fisiologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
15.
Curr Psychiatry Rep ; 19(1): 6, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28138924

RESUMO

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.


Assuntos
Transtorno da Personalidade Borderline/diagnóstico por imagem , Transtorno da Personalidade Borderline/fisiopatologia , Encéfalo/fisiopatologia , Despersonalização/diagnóstico por imagem , Despersonalização/fisiopatologia , Transtornos Dissociativos/diagnóstico por imagem , Transtornos Dissociativos/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Transtorno da Personalidade Borderline/psicologia , Mapeamento Encefálico , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiopatologia , Despersonalização/psicologia , Transtornos Dissociativos/psicologia , Humanos , Sistema Límbico/diagnóstico por imagem , Sistema Límbico/fisiopatologia , Neuroimagem , Transtornos de Estresse Pós-Traumáticos/psicologia
16.
Psychiatry Res ; 240: 4-10, 2016 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-27078753

RESUMO

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.


Assuntos
Barorreflexo/fisiologia , Tronco Encefálico/fisiopatologia , Despersonalização/fisiopatologia , Reflexo de Sobressalto/fisiologia , Fibras Aferentes Viscerais/fisiopatologia , Estimulação Acústica , Adulto , Encéfalo/fisiopatologia , Potenciais Evocados/fisiologia , Feminino , Coração/fisiopatologia , Frequência Cardíaca/fisiologia , Humanos , Masculino
17.
Psychol Trauma ; 8(5): 592-600, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27100173

RESUMO

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


Assuntos
Comportamento do Adolescente/psicologia , Despersonalização/fisiopatologia , Transtornos Dissociativos/fisiopatologia , Delinquência Juvenil/psicologia , Escalas de Graduação Psiquiátrica/normas , Trauma Psicológico/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adolescente , Transtornos Dissociativos/diagnóstico , Feminino , Humanos , Masculino
18.
Psychiatry Res ; 240: 118-122, 2016 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-27104926

RESUMO

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.


Assuntos
Despersonalização/terapia , Córtex Pré-Frontal/fisiopatologia , Estimulação Magnética Transcraniana/métodos , Adulto , Despersonalização/fisiopatologia , Feminino , Humanos , Londres , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Projetos de Pesquisa , Resultado do Tratamento
19.
Soc Cogn Affect Neurosci ; 11(6): 945-51, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26940563

RESUMO

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.


Assuntos
Neoplasias Encefálicas/complicações , Córtex Cerebral , Hemorragia Cerebral/complicações , Transtornos Dissociativos/fisiopatologia , Emoções/fisiologia , Neoplasias Neuroepiteliomatosas/complicações , Convulsões/fisiopatologia , Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , Despersonalização/etiologia , Despersonalização/fisiopatologia , Imagem de Tensor de Difusão , Transtornos Dissociativos/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Vias Neurais/patologia , Vias Neurais/fisiopatologia , Convulsões/etiologia
20.
Eur J Neurosci ; 43(7): 971-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26791018

RESUMO

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.


Assuntos
Nível de Alerta , Cognição , Despersonalização/fisiopatologia , Resposta Galvânica da Pele , Adulto , Associação , Sistema Nervoso Autônomo/fisiopatologia , Estudos de Casos e Controles , Função Executiva , Feminino , Lobo Frontal/fisiopatologia , Humanos , Sistema Límbico/fisiopatologia , Masculino , Teste de Stroop
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...