Dissociative Part-Dependent Resting-State Activity in Dissociative Identity Disorder: A Controlled fMRI Perfusion Study

Abstract

BackgroundIn accordance with the Theory of Structural Dissociation of the Personality (TSDP), studies of dissociative identity disorder (DID) have documented that two prototypical dissociative subsystems of the personality, the “Emotional Part” (EP) and the “Apparently Normal Part” (ANP), have different biopsychosocial reactions to supraliminal and subliminal trauma-related cues and that these reactions cannot be mimicked by fantasy prone healthy controls nor by actors.MethodsArterial spin labeling perfusion MRI was used to test the hypotheses that ANP and EP in DID have different perfusion patterns in response to rest instructions, and that perfusion is different in actors who were instructed to simulate ANP and EP. In a follow-up study, regional cerebral blood flow of DID patients was compared with the activation pattern of healthy non-simulating controls.ResultsCompared to EP, ANP showed elevated perfusion in bilateral thalamus. Compared to ANP, EP had increased perfusion in the dorsomedial prefrontal cortex, primary somatosensory cortex, and motor-related areas. Perfusion patterns for simulated ANP and EP were different. Fitting their reported role-play strategies, the actors activated brain structures involved in visual mental imagery and empathizing feelings. The follow-up study demonstrated elevated perfusion in the left temporal lobe in DID patients, whereas non-simulating healthy controls had increased activity in areas which mediate the mental construction of past and future episodic events.ConclusionDID involves dissociative part-dependent resting-state differences. Compared to ANP, EP activated brain structures involved in self-referencing and sensorimotor actions more. Actors had different perfusion patterns compared to genuine ANP and EP. Comparisons of neural activity for individuals with DID and non-DID simulating controls suggest that the resting-state features of ANP and EP in DID are not due to imagination. The findings are consistent with TSDP and inconsistent with the idea that DID is caused by suggestion, fantasy proneness, and role-playing.

Similar cortical but not subcortical gray matter abnormalities in women with posttraumatic stress disorder with versus without dissociative identity disorder

“…Experiencing dissociation of self from the body might thus relate to failure to integrate complex somatosensory and vestibular cues (Blanke et al, 2002;Blanke and Arzy, 2005;De Ridder et al, 2007). In line with this idea, the involvement of the parietal regions has previously been indicated in functional neuroimaging studies in DID (Reinders et al, 2003(Reinders et al, , 2006Schlumpf et al, 2014) and depersonalization disorder (Simeon et al, 2000). Altogether, our findings along with previous reports suggest that the inferior parietal cortex plays a role in the neurobiology of dissociative and depersonalization symptoms in DID and PTSD.…”

An Ontological Solution to the Mind-Body Problem

“…2-30; [3], pp. [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30]. This is a well-known problem in neuroscience and philosophy of mind, often referred to as the 'hard problem of consciousness'.…”

“…In another study [23], doctors performed fMRI brain scans on both DID patients and actors simulating DID. The scans of the actual patients displayed clear and significant differences when compared to those of the actors.…”

“…By now this shouldn't come as a surprise: recall that, in Inference 3, I've posited that the physical universe is, in a specific sense, akin to a 'nervous system'. Recall also that a study has shown that dissociative processes in the nervous systems of DID patients have a distinct extrinsic appearance, detectable by brain scans [23]. Therefore, it is plausible that dissociation in the universal 'nervous system' should also have a distinct extrinsic appearance.…”

‘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 ., ).…”