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.

Pineal gland and schizophrenia: A systematic review and meta-analysis.

Melatonin (MLT), the main hormone of the pineal gland (PG), is assumed to support initiation and maintenance of sleep, and a stable sleep-wake cycle, exerting antioxidative and neuroprotective actions. Evidence demonstrates that sleep and circadian rhythm abnormalities are very common in schizophrenia patients. Some imaging studies suggest structural abnormalities of the PG in these patients as well. We aimed to critically appraise the literature on PG imaging and melatonin secretion in schizophrenia patients, in comparison to matched healthy controls, and to review placebo-controlled trials of add-on exogenous MLT treatment in schizophrenia patients. In this systematic review, twenty-nine studies were included. Meta-analytical evaluation of data was possible only for MLT secretion finding that midnight plasma levels were significantly reduced in individuals with schizophrenia as compared to healthy controls (Hedge`s g = 1.32, p < 0.01). Imaging studies demonstrated greater prevalence of enlarged calcifications (>1 cm) of the PG (2 out of 2 computed tomography studies) and smaller PG volume (2 out of 3 magnetic resonance studies) compared with healthy controls. Anatomic and functional abnormalities of the PG were not associated with duration of illness or with treatment factors, maybe suggesting them to be primary characteristics of the disease and genetically based. Add-on MLT treatment leads to a modest improvement of objective and subjective sleep quality, of metabolic adverse effects of antipsychotics, and of tardive dyskinesia symptoms in schizophrenia patients. It remains to be established whether MLT treatment in prodromal phases of the disease could prevent neurostructural abnormalities.

Altered cardiovascular vagal responses in nonelderly female patients with subclinical hyperthyroidism and no apparent cardiovascular disease.

OBJECTIVE: Subclinical hyperthyroidism (SH) has been associated with exercise intolerance, changes in cardiac morphology, atrial arrhythmias and sympathovagal imbalance. The aim of this study was to evaluate the vagal reserve and modulation by a sympathetic stimulus in nonelderly patients with SH without cardiovascular problems. DESIGN: We carried out a cross-sectional study, comparing data of the heart rate variability (HRV) of SH patients and healthy controls at rest and after vagal and sympathetic stimulation. PATIENTS: We studied 16 female patients with at least 6 months of SH and 16 healthy female controls with the same median age (40 vs. 34.5 years). MEASUREMENTS: We used the tilt test, with electrocardiographic record at rest, during the respiratory sinus arrhythmia (RSA) manoeuvre and after tilting, in order to analyse HRV in the frequency domain (%high frequency (HF) and low/high frequency ratio (LF/HF) using Biopotentials Captation System software. RESULTS: The median TSH level was 0.03 mU/l in patients and 1.37 mUI/l in controls. The median free T4 was 1.37 ng/dl in patients and 1.20 ng/dl in controls. Patients demonstrated a significantly smaller difference between %HF during the RSA and %HF at rest than controls (median -7.5 vs. 36.6, P < 0.001). There was a lower difference between LF/HF ratio after tilting and LF/HF ratio at rest in patients than in controls (1.5 vs. 5.3, P = 0.005). CONCLUSION: Subclinical hyperthyroidism affects cardiovascular autonomic balance in otherwise apparently healthy nonelderly females by blunting vagal responses.

Exercise performance in young and middle-aged female patients with subclinical hyperthyroidism.

Subclinical hyperthyroidism (SH) may be responsible for many cardiovascular changes, including an impaired exercise performance. The aim of our study was to evaluate the response to the treadmill cardiopulmonary test in patients with SH. We studied 14 female patients from our endocrine clinic with exogenous SH, free from cardiovascular diseases, with mean age of 38.6 +/- 10.2 years, body mass index (BMI) of 24.4 +/- 4.0 kg/m(2), and disease duration of 4.9 +/- 4.9 years. The mean serum thyrotropin (TSH) was 0.03 +/- 0.03 mU/L, serum free thyroxine (FT(4)), 1.72 +/- 0.21 ng/dL, and serum triiodothyronine level, 137 +/- 32 ng/dL. The control group comprised 15 euthyroid, healthy women, with mean age of 35.4 +/- 7.4 years and BMI of 27.3 +/- 5.9 kg/m(2). Both groups had a sedentary lifestyle and underwent the cardiopulmonary test using a treadmill with the Balke protocol. Gas concentrations and the respiratory outflow were measured and the electrocardiogram (ECG) was registered in real time. We calculated the minute ventilation (V(E)), the oxygen consumption (peak VO(2)), the carbonic gas exhalation (peak VCO(2)) and the anaerobic threshold (AT). The heart rate (HR) at rest (90.9 +/- 15.7 versus 78.9 +/- 8.7 beats per minute; p = 0.03) was higher in the patients from our clinic. There was no difference between groups regarding age, BMI, fat percentage, blood pressure, peak HR, exercise duration, mean treadmill peak inclination, V(E), peak VO(2), peak VCO(2), and AT. There was no correlation between peak VO(2) and FT(4), TSH, or disease duration. Our results show that exercise capacity in young and middle-aged female patients is not significantly affected by exogenous SH.