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Biology subjects

Schmidt, T. T.

Publications and source records attributed to Schmidt, T. T..

2 recordsLinked to original sources

Is Kambo psychoactive? Acute and subacute effects of the secretion of the Giant Maki Frog (Phyllomedusa bicolor) on human consciousness.

Kambo is the name for the secretion of the Giant Leaf Frog (Phyllomedusa bicolor) containing a plethora of bioactive peptides. Originally, it is ritually used by different ethnicities from the Amazon basin as a remedy against bad luck in hunting. In the last twenty years, Kambo has spread to Western urban centers, often associated with the use of ayahuasca. Anecdotal reports claim beneficial effects on wellbeing and different medical and mental health conditions. However, to date it has been controversial if Kambo elicits altered states of consciousness. Here we retrospectively investigated acute and subacute psychological effects of Kambo in a sample of n = 22 anonymous users (n = 22, mean age: 39 years, {+/-} 8.5; 45.5% female), administering standardized questionnaires for the assessment of psychoactive effects. Acutely, participants reported psychological effects which remained on a mild to moderate level, but no psychedelic-type distortions of perception or thinking. In contrast, persisting effects were predominantly described as positive and pleasant, revealing surprisingly high measures of personal and spiritual significance. Subacute and long-term effects showed some overlap with the "afterglow" phenomena that follow the use of serotonergic psychedelics.

pharmacology and toxicology

How does it feel to be on psilocybin? Dose-response relationships of subjective experiences in humans.

Psilocybin is the active component of magic mushrooms and is well known for its psychoactive properties. Different questionnaires have been developed to systematically quantify altered states of consciousness induced by psychoactive drugs. The aim of this study was to obtain the dose-response relationships of the subjective experiences induced by psilocybin in healthy study participants. For this purpose, we applied a linear meta-regression approach on questionnaire ratings after oral administration of psilocybin in a controlled setting. Data was obtained from The Altered States Database, which contains psychometric data extracted from peer-reviewed articles published in MEDLINE-listed journals that used standardized and validated questionnaires. Our meta-analysis included data of the Altered States of Consciousness Rating Scale, the Mystical Experience Questionnaire (MEQ30), and the Hallucinogen Rating Scale (HRS). We used the Robust Variance Estimation Framework to obtain linear dose-response relationship estimates for each dimension of the given questionnaires. Ratings on most dimensions and subscales of the included questionnaires correlated positively with dose. Since subjective experiences are not only determined by dose, but also by individual differences and environmental factors, our results do not necessarily generalize to recreational use, as our analyses are based on data from controlled laboratory experiments. The paper at hand could serve as a general literature citation for the use of psilocybin in experimental and clinical research, especially for the comparison of expected and observed subjective drug experiences.

neuroscience