The association of multiple personality and temporolimbic epilepsy. Intracarotid amobarbital test observations

A Dual Mind Approach to Understanding the Conscious Self and Its Treatment

In this paper I will address questions about will, agency, choice, consciousness, relevant brain regions, impacts of disorders, and their therapeutics, and I will do this by referring to my theory, Dual-brain Psychology, which posits that within most of us there exist two mental agencies with different experiences, wills, choices, and behaviors. Each of these agencies is associated as a trait with one brain hemisphere (either left or right) and its composite regions. One of these agencies is more adversely affected by past traumas, and is more immature and more symptomatic, while the other is more mature and healthier. The theory has extensive experimental support through 17 peer-reviewed publications with clinical and non-clinical research. I will discuss how this theory relates to the questions about the nature of agency and I will also discuss my published theory on the physical nature of subjective experience and its relation to the brain, and how that theory interacts with Dual-Brain Psychology, leading to further insights into our human nature and its betterment.

Dissociation, Epileptiform Discharges and Chaos in the Brain: Toward a Neuroscientific Theory of Dissociation

Dissociated states represent pathological conditions when psychological trauma may emerge in a variety of forms such as psychic dissociative symptoms or, on the contrary, as paroxysms or other somatoform symptoms. There is evidence that epileptic activity plays an important role in the generation of dissociative states and it is able to generate various psychopathological processes as well as a wide spectrum of somatic symptoms or seizures. For the explanation of these connections between dissociative states and epileptic discharges the author proposes a neuroscientific model of dissociation based on the theory of competitive neural assemblies which can lead to chaotic self-organization in brain neural networks. This model is suggested as an integrative view interconnecting the various psychopathological and somatoform manifestations of dissociative states and suggests further possibilities for future research regarding common pathogenic mechanisms among epilepsy and mental disorders.

Dissociative part-dependent resting-state activity in dissociative identity disorder: a controlled FMRI perfusion study

BACKGROUND

In 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.

METHODS

Arterial 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.

RESULTS

Compared 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.

CONCLUSION

DID 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.

Hypnotic abreaction releases chaotic patterns of electrodermal activity during dissociation

Chaotic transitions emerge in a wide variety of cognitive phenomena and may possibly be linked to specific changes during development of mental disorders. There are several hypotheses that link the dissociation to critical chaotic shifts with the resulting self-organization of behavioral patterns during critical periods. In 2 patients, hypnotic revivification of dissociated trauma along with measurement of bilateral electrodermal activity (EDA) for therapeutic and research purposes was performed. Nonlinear data analysis of EDA records shows a difference between degree of chaos in hypnotic relaxed state before revivification of the trauma and dissociated state after reliving the traumatic memory. Results suggest that the dissociated state after revivification of the trauma is significantly more chaotic than the state during the hypnotic relaxation before the event. Findings of this study suggest a possible role of neural chaos in the processing of the dissociated traumatic memory during hypnotic revivification.

Determination of hemispheric emotional valence in individual subjects: a new approach with research and therapeutic implications

BACKGROUND

Much has been theorized about the emotional properties of the hemispheres. Our review of the dominant hypotheses put forth by Schore, Joseph, Davidson, and Harmon-Jones on hemispheric emotional valences (HEV) shows that none are supported by robust data. Instead, we propose that individual's hemispheres are organized to have differing HEVs that can be lateralized in either direction.

METHODS

Probe auditory evoked potentials (AEP) recorded during a neutral and an upsetting memory were used to assess HEV in 28 (20 F) right-handed subjects who were either victims of childhood maltreatment (N = 12) or healthy controls. In a sub-population, we determined HEV by emotional response to lateral visual field stimulation (LVFS), in which vision is limited to one, then the other hemifield. We compare a number of morphometric and functional brain measures between individuals who have right-negative versus left-negative HEV.

RESULTS

Using AEPs to determine HEV, we found 62% of controls and 67% of maltreated subjects had right negative HEV. There was a strong interaction between HEV-laterality and gender, which together accounted for 60% of individual variability in total grey matter volume (GMV). HEV-laterality was associated with differences in hippocampal volume, amygdala/hippocampal ratios, and measures of verbal, visual and global memory. HEV-laterality was associated also with different constellations of symptoms comparing maltreated subjects to controls. Emotional response to LVFS provided a convenient and complementary measure of HEV-laterality that correlated significantly with the HEVs determined by AEPs.

CONCLUSION

Our findings suggest that HEV-laterality, like handedness or gender, is an important individual difference with significant implications for brain and behavioral research, and for guiding lateralized treatments such as rTMS.

P300 is attenuated during dissociative episodes

The present study examined the pathophysiology of dissociative phenomena using the P300 component of event-related potentials, quantitative electroencephalography (QEEG), and morphology measures of computed tomography scan. Event-related potentials during an auditory oddball paradigm and QEEG in resting state were recorded. Patients exhibited attenuation of P300 amplitudes compared with controls during dissociative episodes, but exhibited recovery to control levels in remission. Patients had a larger Sylvian fissure-brain ratio than did controls. QEEG findings revealed no significant differences between the patients and controls or between episodes and remission in the patient group. Attenuation of the P300 can be interpreted as the result of a negative feedback loop from the medial temporal lobe to the cortex, which decreases the amount of information flow, allocation of attentional resources, and updating of working memory to avoid both excessive long-term memory system activity in medial temporal lobe and resurgence of affect-laden memories.

Associations among dissociative experiences, handedness, and demographic variables in a nonclinical population

Handedness is considered an indirect marker for bilateral language capacity in the brain. The Edinburgh Inventory for Handedness and the Dissociative Experiences Scale (DES) were administered to 297 nonclinical volunteers. Female sex, young age, and non-right handedness accounted for 24% of the total variance on the DES, including both pathological and nonpathological dissociative experiences. This is consistent with the hypothesis that cerebral lateralization indicating handedness is a predisposing factor for dissociative episodes especially in female subjects.

Quality of life and personality in adults with epilepsy

PURPOSE

This study was undertaken to understand the quality of life, personality, and associated factors in patients with epilepsy.

METHODS

117 patients with epilepsy and 84 healthy people were studied and tested using the Social Support Scale, the General Well-being Schedule, the Life-Event Scale, the Behavior Pattern Scale, and the Eysenck Personality Questionnaire (EPQ).

RESULTS

There were no significant differences between the patients with epilepsy and the control group in the Social Support Scale results. The General Well-being Schedule scores were lower for the case patients than for the control group (p < 0.01). Scores for patients with frequent seizures (once a month or more) were lower than those without frequent seizures (less than once per month). The case patients had higher negative scores in the family-related problem section of the Life Events Scale, compared with the control group (p < 0.05). The patients with epilepsy were also more likely to lie (p < 0.05); their emotions were more changeable (p < 0.01), and their character more introverted (p < 0.05), although their behavior patterns were similar to the controls. We also studied associated factors related to personality, general well-being, and familial-negative life-events.

CONCLUSIONS

These results provide information about patients with epilepsy that may be useful in their psychological treatment.

Affect changes observed with right versus left lateral visual field stimulation in psychotherapy patients: possible physiological, psychological, and therapeutic implications

Seventy psychotherapy patients were given two pairs of goggles each taped over to allow vision from only the left or the right lateral visual field (LVF and RVF). Sixty percent reported at least a one-point difference between visual fields on a five-point anxiety scale; 23% reported at least a two-point difference. Among 21 patients with major depression, 11 reported greater anxiety through the LVF, four reported greater anxiety through the RVF, and six reported no difference. Among 18 with posttraumatic stress disorder (PTSD), 10 reported greater anxiety from the RVF and four from the LVF, and four reported no difference. The absolute difference in anxiety ratings was significantly greater (P < .001) between the two pairs of experimental goggles than between two pairs of control goggles allowing monocular vision among 40 patients in whom the four pairs were tested. During a subsequent psychiatric interview, 40 of 49 patients who were responsive while using the experimental goggles manifested an intensification of their usual symptoms on one side and an alleviation on the other. The possible physiological, psychological, and therapeutic implications of these findings are discussed.