Dissociation and Brain Rhythms: Pitfalls and Promises

Recently, Vesuna et al. proposed a novel circuit mechanism underlying dissociative states using optogenetics and pharmacology in mice in combination with intracranial recordings and electrical stimulation in an epilepsy patient. Specifically, the authors identified a posteromedial cortical delta-rhythm that underlies states of dissociation. In the following, we would like to critically review these findings in the context of the human literature on dissociation as well as highlight the challenges in translational neuroscience to link complex behavioral phenotypes in psychiatric syndromes to circumscribed circuit mechanisms.

Djinnati syndrome as the first manifestation of temporal lobe epilepsy: A case report

Culture-bound syndromes are a group of abnormal behavior patterns occurring only in definite cultural groups. As a form of culture-bound syndromes, possession trance is known as the “replacement of personal identity customary sense by a new identity.” Djinnati syndrome is a possession state restricted to specific areas of Iranian and Pakistani Baluchestan. Preceding studies suggested that complex behavioral manifestations of temporal lobe epilepsy (TLE) were likely to contain dissociative states symptoms. Nonetheless, people in numerous developing countries hold a belief that Jinn possession causes epilepsy even in quite well-educated people. The aims of the present report are to describe a patient who presented Djinnati syndrome as the very first manifestation of TLE and address the feasible detrimental impacts of cultural misconceptions on diagnosing and treating epileptic seizures.

ENERGIES AND VIBRATIONAL MODES OF SPECIES FORMED BY DEHYDROGENATION OF CH4 IN PRESENCE OF O2 OVER Cr2O3(0001)

In this work we perform a theoretical study of dehydrogenation process of CH4 on O2– in both molecular and dissociative states - previously adsorbed on Cr2O3(0001). Calculations are based on Density Functional Theory (DFT). The results show the methanol formation form the adsorption of CH4 on O2 in dissociative state with a formationenergy5:14 eV. Also formaldehyde was formed by the reaction of CH2with molecular O2(Eads=6:09 eV) and dioxymethylene by the reaction of CH2with O2 previously adsorbed in dissociative state on Cr2O3(0001), withEads=8:17 eV. Finally, the vibrational modes found by DFT for each of the species were compared, which are in good agreement with those of reference bibliography. This allows us to support the values found both by technical calculations and by experimental methods.

Mystical-type experiences occasioned by ketamine mediate its impact on at-risk drinking: Results from a randomized, controlled trial

Background: Sub-anesthetic ketamine administration may be helpful for substance use disorders. Converging evidence suggests that the efficacy of ketamine for certain conditions may implicate a subset of its psychoactive effects. Aims: The aim of this analysis is to evaluate whether the mystical-type effects of ketamine are critical for clinical efficacy in alcohol-dependent individuals. In this secondary analysis, we determine if a subset of the psychoactive effects of ketamine, the so-called mystical-type experience, mediates the effect of ketamine, when combined with motivational enhancement therapy, on at-risk drinking behavior in alcohol-dependent individuals interested in treatment. Methods: Forty alcohol dependent adults were randomized to either a 52-minute infusion of ketamine or midazolam, which they received on a designated quit-day during the second week of a five-week motivational enhancement therapy regimen. Psychoactive effects were assessed following the infusion, and alcohol use was monitored for the subsequent 3 weeks at each twice-weekly visit. Results: We found that ketamine leads to significantly greater mystical-type effects (by Hood Mysticism Scale) and dissociation (by Clinician Administered Dissociative States Scale) compared to the active control. Ketamine also led to significant reduction in at-risk drinking. The Hood Mysticism Scale, but not Clinician Administered Dissociative States Scale score, was found to mediate the effect of ketamine on drinking behavior. Conclusions: This trial adds evidence to the literature on the importance of mystical-type experiences in addiction treatment. Future research should continue to investigate the relationship between the psychoactive effects of psychedelic therapeutics and clinical outcomes for other substance use and mental health disorders.