The Psychobiology of Authentic and Simulated Dissociative Personality States

Abstract

The etiology of dissociative identity disorder (DID) remains a topic of debate. Proponents of the fantasy model and the trauma model of DID have both called for more empirical research. To this end, the current study presents new and extended data analyses of a previously published H2O positron emission tomography imaging study. This study included 29 subjects: 11 patients with DID and 10 high- and 8 low-fantasy-prone DID-simulating mentally healthy control subjects. All subjects underwent an autobiographical memory script-driven (neutral and trauma related) imagery paradigm in 2 (simulated) dissociative personality states (neutral and trauma related). Psychobiological and psychophysiological data were obtained. Results of the new post-hoc tests on the psychophysiological responses support the trauma model. New results of the brain imaging data did not support the fantasy model. This study extends previously published results by offering important new supporting data for the trauma model of DID.

Neurodevelopmental origins of abnormal cortical morphology in dissociative identity disorder

“…These results are now presented in Table and Figure . While these results need to be interpreted with care due to uncorrected significance levels, it is important to note that the neuroanatomical correlates of very early traumatization overlap with many brain areas previously noted in many functional MRI studies examining atypical brain functioning in dissociative personality state during emotion regulation, such as parietal regions and prefrontal regions , as well as with previously found neuroanatomical aberrations .…”

“…However, a recent study by our group has also investigated brain abnormalities in DID on the cortical level using an exploratory approach in a set of 68 predefined cortical areas across the cortex and reported that individuals with DID have significantly reduced gray matter volume in the medial and dorsolateral prefrontal cortex, the anterior cingulate, the insular cortex, inferior parietal areas, and in several regions within the temporal lobe . A high degree of overlap was found between these neuroanatomical aberrations and dissociative personality state‐dependent brain functioning during emotion regulation, which showed predominantly activation in the parietal regions, insula and limbic‐prefrontal circuitry . The parietal and insular regions, and the limbic‐prefrontal circuitry of the brain are therefore of pivotal interest in the investigation of brain function and structure in DID.…”

Dissociation debates: everything you know is wrong

“…Simulating controls had markedly different brain activation and psychophysiological patterns from DID patients. 53 In an MRI study, women with DID had significantly reduced hippocampal and amygdalar volumes compared to healthy controls. 54 Many studies have shown a relationship to trauma and reduced hippocampal volume, especially to chronic trauma, thought to be related to the impact on the hippocampus of repeated release of glucocorticoids.…”

“…2,32,52 PET and fMRI studies of DID patients found that selfstates subjectively experiencing traumatic memory scripts as personal autobiographical memory (Traumatic Identity State-TIS) showed patterns of limbic system activation and decreased activity in frontal systems similar to nondissociative PTSD patients, as well as autonomic changes typical of sympathetic hyperarousal. 53 Neutral Identity States (NIS) did not report experiencing trauma scripts as autobiographical memory. NIS showed brain and psychophysiological responses similar to PTSD-DS.…”

‘Janet vs Freud’ on Traumatization: A Critique of the Theory of Structural Dissociation from an Object Relations Perspective

“…Pertinent clinical observations, evidence, explanations, and ways to deal with structural dissociation of the personality are presented in Van der Hart, Nijenhuis and Steele's book The Haunted Self (). Ground‐breaking controlled neuroimaging studies have demonstrated dissociative part‐dependent physiological and neurophysiological reactions to supraliminally and sublimally presented trauma‐related cues (Reinders et al ., ; Schlumpf et al ., ), as well as neurophysiological dissociative part‐dependent resting state differences (Schlumpf et al ., ).…”