Psychometric Evaluation of the Altered States of Consciousness Rating Scale (OAV)

Background: Ketamine is central to one of the most rapidly growing areas of neuroscientific research into novel treatments for depression. Limited research has indicated that the psychedelic properties of ketamine may play a role in its antidepressant effects. Aim: The aim of the current study was to explore the psychedelic experiences and sustained impact of ketamine in major depressive disorder. Methods: In the current study, ketamine (0.44 mg/kg) was administered to 32 volunteers with major depressive disorder in a crossover design with the active-placebo remifentanil, in a magnetic resonance imaging (MRI) environment. The 11-dimension altered states of consciousness questionnaire and individual qualitative interviews were used to capture the acute psychedelic experience. The Montgomery-Asberg Depression Rating Scale and further interviewing explored lasting effects. The second qualitative interview took place ⩾3 weeks post-ketamine. Results: Greater antidepressant response (reduction in Montgomery-Asberg Depression Rating Scale at 24 h) correlated with the 11-dimension altered states of consciousness dimensions: spirituality, experience of unity, and insight. The first qualitative interview revealed that all participants experienced perceptual changes. Additional themes emerged including loss of control and emotional and mood changes. The final interview showed evidence of a psychedelic afterglow, and changes to perspective on life, people, and problems, as well as changes to how participants felt about their depression and treatments. Conclusions: The current study provides preliminary evidence for a role of the psychedelic experience and afterglow in ketamine’s antidepressant properties. Reflexive thematic analysis provided a wealth of information on participants’ experience of the study and demonstrated the psychedelic properties of ketamine are not fully captured by commonly used questionnaires.

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Acute and subacute psychoactive effects of Kambô, the secretion of the Amazonian Giant Maki Frog (Phyllomedusa bicolor): retrospective reports

Scientific Reports ◽

10.1038/s41598-020-78527-4 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Timo Torsten Schmidt ◽

Simon Reiche ◽

Caroline L. C. Hage ◽

Felix Bermpohl ◽

Tomislav Majić

Keyword(s):

Amazon Basin ◽

Rating Scale ◽

Mystical Experience ◽

Indigenous Communities ◽

Altered States Of Consciousness ◽

Psychological Effects ◽

Altered States ◽

Acute Effects ◽

States Of Consciousness ◽

Experience Questionnaire

AbstractKambô, the secretion of the Amazonian Giant Leaf Frog (Phyllomedusa bicolor) contains a plethora of bioactive peptides and was originally used by indigenous communities from the Amazon basin as medicine for improving hunting capacities. In the last 20 years, Kambô has spread to Western urban healing circles. To date it is still controversial whether the acute effects of Kambô include alterations of consciousness similar to known psychoactive substance like serotonergic psychedelics. Here we retrospectively assessed psychological effects of Kambô in a sample of anonymous users (n = 22, mean age: 39 years, ± 8.5; 45.5% female), administering standardized questionnaires for the assessment of altered states of consciousness (ASC), including the Altered States of Consciousness Rating Scale, the Phenomenology of Consciousness Inventory (PCI), the Mystical Experience Questionnaire (MEQ), the Challenging Experience Questionnaire (CEQ) for acute effects and the Persisting Effects Questionnaire (PEQ) and a scale assessing connectedness for subacute effects. The intensity of retrospectively reported acute psychological effects remained on a mild to moderate level, with no psychedelic-type distortions of perception or thinking. Conversely, persisting effects were predominantly described as positive and pleasant, revealing high scores on measures of personal and spiritual significance.

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Phenomenological assessment of psychedelic induced experiences: Translation and validation of the German Challenging Experience Questionnaire (CEQ) and Ego-Dissolution Inventory (EDI)

10.31234/osf.io/kxmgq ◽

2021 ◽

Author(s):

Katharina Dworatzyk ◽

Tallulah Jansen ◽

Timo Torsten Schmidt

Keyword(s):

Factor Analysis ◽

Factor Structure ◽

Convergent Validity ◽

Rating Scale ◽

Altered States Of Consciousness ◽

Altered States ◽

States Of Consciousness ◽

Confirmatory Factor ◽

Translation And Validation ◽

Experience Questionnaire

Several measures have been designed to assess subjective experiences induced by psychedelic substances and other mind-altering drugs or non-pharmacological methods. Recently, two self-report questionnaires have been introduced to measure acute adverse effects following psilocybin ingestion and the phenomenon of ego-dissolution associated with psychedelic use, respectively. The 26-item Challenging Experience Questionnaire assesses multiple dimensions of psilocybin induced experiences, whereas the 8-item Ego-Dissolution Inventory consists of a uni-dimensional scale. In the present study, these questionnaires were translated into German and their psychometric properties then evaluated in an online survey on psychedelic induced experiences. Confirmatory factor analysis confirmed the 7-factor structure of the German Challenging Experience Questionnaire with overall good internal consistency for all subscales. The factor structure did not differ based on gender or prior struggle with anxiety or depression, furthering the evidence of internal validity. Correlations with the State-Trait-Anxiety Inventory and the Altered States of Consciousness Rating Scale demonstrated convergent validity. Confirmatory factor analysis did not confirm the hypothesized single-factor structure of the German Ego-Dissolution Inventory and exploratory factor analysis suggested an alternative factor structure, where only five items loaded onto a common factor that was interpreted as ego-dissolution. Internal consistency of this 5-item measure was high and correlation with selected items of the Mystical Experience Questionnaire and Altered States of Consciousness Rating Scale supported convergent validity. Translation and validation of these questionnaires contribute to the advancement of common standards in the psychological and neuroscientific study of altered states of consciousness.

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

10.1101/2020.06.09.142802 ◽

2020 ◽

Author(s):

Tim Hirschfeld ◽

Timo Torsten Schmidt

Keyword(s):

Dose Response ◽

Variance Estimation ◽

Rating Scale ◽

Mystical Experience ◽

Meta Analysis ◽

Altered States Of Consciousness ◽

Altered States ◽

Subjective Experiences ◽

States Of Consciousness ◽

Study Participants

AbstractPsilocybin 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.

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Dose–response relationships of psilocybin-induced subjective experiences in humans

Journal of Psychopharmacology ◽

10.1177/0269881121992676 ◽

2021 ◽

pp. 026988112199267

Author(s):

Tim Hirschfeld ◽

Timo T Schmidt

Keyword(s):

Dose Response ◽

Variance Estimation ◽

Rating Scale ◽

Mystical Experience ◽

Meta Analysis ◽

Altered States Of Consciousness ◽

Altered States ◽

Subjective Experiences ◽

States Of Consciousness ◽

Almost All

Background: Psilocybin is the psychoactive component in Psilocybe mushrooms (‘magic mushrooms’). Whether and how the quality of the psilocybin-induced experience might mediate beneficial health outcomes is currently under investigation, for example, in therapeutic applications. However, to date, no meta-analysis has investigated the dose-dependency of subjective experiences across available studies. Aim: Establishing dose–response relationships of the subjective experiences induced by psilocybin in healthy study participants and a comparison of patient groups. Method: We applied a linear meta-regression approach, based on the robust variance estimation framework, to obtain linear dose–response relationship estimates on questionnaire ratings after oral psilocybin administration. Data were obtained from the Altered States Database, which contains data extracted from MEDLINE-listed journal articles that used standardized and validated questionnaires: the Altered States of Consciousness Rating Scale, the Mystical Experience Questionnaire and the Hallucinogen Rating Scale. Results: Psilocybin dose positively correlated with ratings on most factors and scales, mainly those referring to perceptual alterations and positively experienced ego dissolution. Measures referring to challenging experiences exhibited small effects and were barely modulated by dose. Conclusion: Psilocybin intensified almost all characteristics of altered states of consciousness assessed with the given questionnaires. Because subjective experiences are not only determined by dose, but also by individual and environmental factors, the results may only apply to controlled laboratory experiments and not to recreational use. This paper may serve as a general literature citation for the use of psilocybin in experimental and clinical research, to compare expected and observed subjective experiences.

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