Corpus callosum size, hypnotic susceptibility and empathy in women with alleged mediumship: a controlled study.

AIM: Evidence indicates that highly hypnotizable subjects may have larger area of the rostrum of the corpus callosum (CC). Mediumship can be defined as the alleged ability to communicate regularly with deceased personalities, and self-hypnosis is postulated as an underlying mechanism for this ability. Therefore, we aimed to investigate the CC area, hypnotic susceptibility, self-reported dissociation, and empathy in alleged mediums in comparison with healthy, non-medium controls. METHODS: The study sample consisted of 16 Spiritist mediums (medium group (MG)) and 16 non-medium controls. Magnetic resonance imaging scans were performed to measure the CC areas (total and subdivisions). The Harvard Group Scale of Hypnotic Susceptibility was used to assess hypnotizability, and self-reported measures were used to investigate anomalous experiences, mental health using the Self-Reporting Questionnaire-SRQ, dissociative experiences using the Dissociative Experiences Scale, and empathy using the Interpersonal Reactivity Index. RESULTS: No between-group differences were found in the total or subdivided CC areas or in hypnotizability, with both groups showing intermediate levels. The rostrum of the CC area and hypnotizability were not correlated. The MG presented with significantly more anomalous experiences, but the two groups had similar scores for dissociation, empathy, and mental health. CONCLUSION: The normal CC areas found in the MG are in contrast with the abnormal results typically observed in subjects with psychotic and dissociative disorders. Although hypnotizability was not different between groups, further studies are needed to replicate these findings in other samples.

"Seat of the soul"? The structure and function of the pineal gland in women with alleged spirit possession-Results of two experimental studies.

BACKGROUND: Cultural traditions attribute to pineal gland an important role for spiritual experiences. Mediumship and spirit possession are cultural phenomena found worldwide which have been described as having dissociative and psychotic-like characteristics, but with nonpathological aspects. A sympathetic activation pattern in response to spirit possession has been reported in some studies, but empirical data on pineal gland is scarce in this context. METHODS: We aimed to investigate pineal gland and pituitary volumes, as well as urinary 6-sulfatoxymelatonin levels in 16 alleged mediums (Medium Group-MG) compared with 16 healthy nonmedium controls (Control Group) (Experiment 1). Furthermore, we aimed to evaluate urinary 6-sulfatoxymelatonin and stress reactivity in GM (n = 10) under different physiological conditions (Experiment 2). RESULTS: In Experiment 1, MG presented higher scores of anomalous experiences, but there were no between-group differences regarding mental health or subjective sleep quality. Similar pineal gland and pituitary volumes were observed between groups. There were no between-group differences in urinary 6-sulfatoxymelatonin collected under equivalent baseline conditions. In Experiment 2, the rise of anxiety and heart rate in response to mediumistic experience was intermediate between a nonstressful control task (reading) and a stressful control task (Trier Social Stress Test-TSST). No significant differences were observed in 6-sulfatoxymelatonin urinary levels between the three conditions. The pattern of stress reactivity during the TSST was normal, but with an attenuated salivary cortisol response. CONCLUSION: The normal neuroimaging and stress reactivity findings in MG contrast with the abnormal results usually observed in subjects with psychotic and dissociative disorders.

Comparing the Detection of Endogenous Psychedelics in Individuals With and Without Alleged Mediumistic Experiences.

CONTEXT: Mediumship is the alleged ability to communicate with deceased personalities. Previous studies have suggested that the endogenous psychotomimetic molecules bufotenine (BT) and dimethyltryptamine (DMT) may play a role in the pathogenesis of psychotic disorders. Distortion of perceptions observed during spiritual experiences could supposedly relate to these substances. OBJECTIVE: To compare the presence of BT and DMT in human urine samples between individuals with and without mediumistic experiences. METHODS: All participants (5 from medium's group - MG and 5 from non-medium's group - CG) undertook a single night continuous 6-h urine pool collection (6:00-11:59 PM). Mediums collected urine samples in nights when they reported having experienced mediumistic communication. A sensitive high-performance liquid chromatography-mass spectrometry (HPLC-MS) assay was used. Questionnaires were used to detect common mental disorders symptoms, and to screen and quantify anomalous experiences. RESULTS: DMT was not detected in any urine specimen tested. The presence of BT detection in urine samples was greater in CG (2/5) than in MG (1/5), with no significant differences (p > 0.99). MG reported more anomalous experiences than CG (6.6±0.8 vs. 2.2±1.5, p = 0.03), but there was no difference concerning their mental health. CONCLUSION: There were no differences between individuals with and without alleged mediumistic experiences concerning endogenous psychedelics. Both BT and DMT are highly sensitive to metabolism by monoamine oxidase and to N-oxidation, and do not survive in the periphery for long. Alternative strategies should be considered to further investigate the putative role of the endogenous psychedelics pathway for the spiritual experiences.

Physiologic correlates of culture-bound dissociation: A comparative study of Brazilian spiritist mediums and controls.

Mediumship and spirit possession are cultural phenomena found in many societies worldwide. In Brazil, Spiritism (a tradition in which mediumship is emphasized) is the third largest religious denomination. The present study aimed to investigate physiologic correlates of nonpathological dissociative experiences by comparing 20 female spiritist mediums with several years of socially sanctioned practice to 20 female nonmedium control subjects from the same religious context. We measured plasma levels of hormones and neuroactive substances, as well as vital signs and heart rate variability (HRV) parameters, before and immediately after spirit communication. Although no between-group differences were noted in basal physiological parameters, in response to the possession experiences the groups differed in heart rate and in plasma concentrations of noradrenaline, thyroid-stimulating hormone (TSH), prolactin, and creatine phosphokinase (CPK). The changes in parameters indicated an arousal response in mediums and a relaxation response in control participants, and the same pattern of changes was observed in HRV parameters from each group during the possession experiences. However, the changes in physiologic parameters for mediums were mild and of short duration: 1 hour after the possession experiences, no difference in cardiac autonomic regulation was noted. No significant group effect was noted for melatonin. Cognitive control processes may explain the arousal associated with the dissociative state. Findings from this study suggest that pathological and nonpathological dissociation may have different physiological correlates.

Historical and cultural aspects of the pineal gland: comparison between the theories provided by Spiritism in the 1940s and the current scientific evidence.

Significance has been attached to the pineal gland in numerous different cultures and beliefs. One religion that has advanced the role of the pineal gland is Spiritism. The objective of the present study was to compile information on the pineal gland drawing on the books of Francisco Cândido Xavier written through psychography and to carry out a critical analysis of their scientific bases by comparing against evidence in the current scientific literature. A systematic search using the terms "pineal gland" and "epiphysis" was conducted of 12 works allegedly dictated by the spirit "André Luiz". All information on the pineal having potential correlation with the field of medicine and current studies was included. Specialists in the area were recruited to compile the information and draw parallels with the scientific literature. The themes related to the pineal gland were: mental health, reproductive function, endocrinology, relationship with physical activity, spiritual connection, criticism of the theory that the organ exerts no function, and description of a hormone secreted by the gland (reference alluding to melatonin, isolated 13 years later). The historical background for each theme was outlined, together with the theories present in the Spiritist books and in the relevant scientific literature. The present article provides an analysis of the knowledge the scientific community can acquire from the history of humanity and from science itself. The process of formulating hypotheses and scientific theories can benefit by drawing on the cultural aspects of civilization, taking into account so-called non-traditional reports and theories.