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Matthias Michal

Publications and source records attributed to Matthias Michal.

9 recordsLinked to original sources
PubMed2007

Pain response in depersonalization: a functional imaging study using hypnosis in healthy subjects.

BACKGROUND: Depersonalization (DP) is characterized by persistent or recurrent episodes of detachment from one's self with reduced pain perception being a common feature. Alterations in the body schema similar to the cortico-limbic disconnection syndrome of pain asymbolia are suggested to be responsible for DP. In this study we used hypnosis to induce DP in healthy subjects and to examine neural patterns of pain perception in the state of DP by means of functional magnetic resonance imaging (fMRI). METHODS: Pain perception was investigated in 7 healthy subjects with high susceptibility to hypnosis in three different mental states: waking state (N-W), hypnotic relaxation (H-R) and hypnotic DP (H-DP). Pain was induced with electrical stimulation to the median nerve at the right wrist. fMRI measurements were performed during all states. RESULTS: Nociceptive stimuli led to an activation of the well described pain network including somatosensory and insular regions and the cerebellum. Activation was markedly reduced in the contralateral somatosensory cortex, parietal cortex (Brodmann area 40, BA40), prefrontal cortex (BA9), putamen and the ipsilateral amygdala during H-DP. Subjects also reported a significant decrease in pain intensity from N-W to H-DP. CONCLUSION: Pain response during H-DP was reduced in sensory and affective pain-related areas, reflecting the diminished intensity of the perceived pain. Moreover, a network of cortical and subcortical areas that have been implicated in the perception of the own body was less responsive during DP, which might point to a specific neural mechanism underlying the 'out-of-body' experience. Although the small number of subjects does not allow a generalization of our findings, H-DP seems to be a promising tool for the investigation of psychological and biological mechanisms of self-inflicted injuries as well as the mind-body interplay within the realm of psychosomatic disorders.

Adult↗
PubMed2005

Spontaneous dissociation during functional MRI experiments.

It is assumed that the procedures of functional magnetic resonance imaging (fMRI) are able to provoke significant dissociative responses. Trait and state dissociation of 32 healthy subjects undergoing fMRI have been recorded. At least one-third of the subjects showed dissociative responses of very large effect size (d=4.10). The contributing causal factors for that dissociative response could not yet identified clearly. Considering the impact of dissociation on mental functions, we recommend controlling subjects undergoing fMRI studies for dissociative responses. Further studies on the actual phenomenological experience of subjects undergoing fMRI procedures are warranted.

Adult↗
PubMed2005

[The validity of the depersonalisation-derealisation scale of the narcissism--inventory].

The German Narcissism-Inventory contains a 6-item scale for the assessment of depersonalization (DP) and derealization (DR). The validity of this scale (NI-DRP) was examined in comparison to the German version of the Dissociative Experiences Scale (FDS) and the Cambridge Depersonalization Scale (CDS). The sample consists of 144 psychotherapy patients, of whom showed on the basis of a structured clinical interview n = 51 none, n = 45 mild, n = 28 moderate and n = 20 severe DP-DR. The areas under the curve and the rate of misclassification did not differ for NI-DRP and the scales of the FDS. The CDS showed the lowest rate of misclassifications.

Adult↗
PubMed2005

Depersonalization and social anxiety.

Although the literature on depersonalization (DP) indicates links between DP and anxiety disorders, there has been no systematic investigation of the association of DP with social anxiety. The present study explores a hypothesized connection between DP and social anxiety by using correlative and regression analyses in a sample of 116 psychotherapy inpatients, 54 outpatients with epilepsy, and 31 nonpatients. Corresponding to our hypothesis, we found a connection of medium to large effect size between DP and social fears exceeding the impact of general psychopathologic symptom severity both for the psychotherapy patients and the nonpatients. The association of social anxiety with DP merits further research. A general consideration of DP in clinical and neurobiological trials on anxiety disorders like social phobia is warranted.

Adolescent↗
PubMed2004

[Convergence of psychotherapeutic and neurobiological outcome measure in a patient with OCD].

We used psychotherapeutic measures and functional magnetic resonance imaging (fMRI) to assess the effect of a combined psychodynamic and cognitive behavioral treatment of a patient suffering from a severe obsessive compulsive disorder (OCD). The clinical outcome was controlled by a detailed case description and psychometric test instruments. Intensive exploration of the patient made possible the creation of an idiosyncratic imagination paradigm suitable for fMRI. The patient shows at the end of treatment a decrease in symptoms as assessed by clinical as well as psychometric instruments. Especially recapitulation and cleaning obsessions decreased, but the cognitive avoidance strategies remained almost unchanged. fMRI showed no orbito-fronto-striatothalamic activation corresponding to obsessive compulsive symptoms, but an increased activation of the medial prefrontal (MFC) and anterior cingulate cortex (ACC). The lack of activation of the orbito-fronto-striatothalamic circuits and at the same time the occurrence of the increased activation of the MFC and ACC reflects the cognitive avoidance strategies still triggered by the symptom provoking stimulus.

Adult↗
PubMed2004

[Assessment of the depersonalization-derealization syndrome using the German version of the Dissociative Experiences Scale].

OBJECTIVES: The goal of this study is to investigate the applicability of the German adaptation of the Dissociative Experiences Scale, the "Fragebogen zu dissoziativen Symptomen (FDS)", for research on depersonalization (DP) and derealization (DR), and to elucidate the phenomenology of DP / DR. METHODS: 101 consecutively recruited inpatients were diagnosed with the German version of the Structured Clinical Interview for DSM-IV Dissociative Disorders for depersonalization/derealization. Furthermore, the FDS and the SCL-90-R were administered. RESULTS: 47 of 101 Patients were diagnosed with pathological DP / DR. The mean score of the DES scale of the FDS was 32.00 +/- 15.52. A cut-off score of 17.5 for the DES scale of the FDS yielded a 83.0 % sensitivity and 77.8 % specificity. Depressive disorders, anxiety disorders and trauma-associated disorders were the most common comorbidity. CONCLUSIONS: The findings are comparable to the Anglo-American samples. The FDS was found to be quite effective for screening of DP / DR. The three-factor solution of the FDS was not well supported in this sample.

Adult↗
PubMedDate not supplied

[The measurement of the depersonalisation-derealisation-syndrome with the German version of the Cambridge Depersonalisation Scale (CDS)].

Self-rating scales have proved to be essential in the study of depersonalisation, which regrettably, is still seldom recognised in clinical practice. In recent studies the Cambridge Depersonalisation Scale (CDS) has emerged as an useful instrument for the study of depersonalisation. Here we report a validation study of the authorised German version of the CDS in a sample of 91 inpatients, 43 of whom had pathological depersonalisation and 48 without pathological depersonalisation. The SCID-D Interview for depersonalisation and derealisation was used as the gold standard and the German version of the Dissociative Experiences Scale was used to test the external validity of the scale. The German version of the CDS was found to have high internal consistency and reliability (alpha = 0,95 and Guttman Split-half = 0,95) and could differentiate patients with pathological depersonalisation from the control group. We therefore conclude that the German version of the CDS can be considered as reliable and valid.

Depersonalization↗
PubMedDate not supplied

[Depersonalization, social phobia and shame].

Associations between depersonalization (DP) and social phobia (SP) were described in the early scientific literature. This connection, however, has not yet been considered in the recent empirical literature and clinical trials on SP. The aim of this study is to examine these associations. In a sample of 100 consecutive inpatients we compare 45 patients with pathological DP to 55 patients without pathological DP with respect to comorbidity and the degree of social anxieties assessed with the SOCIAL INTERACTION ANXIETY SCALE (SIAS) and with the SOCIAL PHOBIA SCALE (SPS) and the extent of shame assessed with the INTERNALIZED SHAME SCALE (ISS). Social phobia was significantly more prevalent in the patients with pathological DP. Furthermore, the patients with pathological DP showed a significantly larger extent of social anxieties (SIAS, SPS) and shame (ISS). The results may be considered as a preliminary empirical support of the assumed associations and thus warrant an enhanced consideration of DP in therapy and research of social anxiety disorders.

Depersonalization↗