Restricted accessResearch articleFirst published online 2024-10
Altered states of consciousness in Danish healthy volunteers and recreational users of psilocybin and the possible impact of setting and intention: Danish validation of the five-dimensional altered states of consciousness questionnaire
Psychedelic substances reliably induce marked altered states of consciousness (ASC), which may be important for lasting effects and clinical outcomes of psychedelic intervention. Several instruments are available to measure the acute psychedelic experience, of which the Five Dimensional Altered States of Consciousness Questionnaire (5D-ASC) is commonly used. The questionnaire can be scored and analyzed as having five dimensions or 11 subscales, but the two have not been evaluated with comparable factor analysis methods.
Methods:
The Danish translation of the 5D-ASC was completed by one sample of healthy volunteers receiving psilocybin in a laboratory setting (N = 47) and one sample of recreative users5D-ASC of psychedelics (N = 550), who reported retrospectively through an online survey based on their most recent experience with psilocybin. We calculated internal consistency measures of Cronbach’s alpha and McDonald’s omega, conducted a confirmatory factor analysis of the previously suggested factor structures, and tested for possible associations between the 5D-ASC total scores and dose, setting, and intention. For the 11 subscales, we reported omega-sem (composite reliability) using the parameters of the fitted confirmatory factor analyses model.
Results:
Confirmatory factor analysis showed that the 11 subscales had a good fit to data and showed a better fit compared to the originally proposed five-dimensional solution and good internal consistencies. We further found that the 5D-ASC total scores correlated positively with the dose in the recreative sample. We found no correlations between 5D-ASC total scores and intention or setting.
Discussion:
We find the Danish 5D-ASC to be a valid tool for measuring ASC among Danish-speaking individuals.
BeckerAMKlaiberAHolzeF, et al. (2023) Ketanserin reverses the acute response to LSD in a randomized, double-blind, placebo-controlled, crossover study in healthy participants. Int J Neuropsychopharmacol26: 97–106.
BodmerI (1989) Konstruktion des Fragebogens OAV zut quantitativen Erfassung auβergewöhnlicher Bewuβtseinszustände (ABZ). Zurich, Switzerland: University of Zurich.
4.
BogenschutzMPForcehimesAAPommyJA, et al. (2015) Psilocybin-assisted treatment for alcohol dependence: A proof-of-concept study. J Psychopharmacol29: 289–299.
5.
BogenschutzMPRossSBhattS, et al. (2022) Percentage of heavy drinking days following psilocybin-assisted psychotherapy versus placebo in the treatment of adult patients with alcohol use disorder: A randomized clinical trial. JAMA Psychiatry79: 953–962.
6.
BousoJCGonzálezDFondevilaS, et al. (2012) Personality, psychopathology, life attitudes and neuropsychological performance among ritual users of Ayahuasca: A longitudinal study. PLoS One7: e42421.
7.
Carhart-HarrisRLBolstridgeMRuckerJ, et al. (2016) Psilocybin with psychological support for treatment-resistant depression: An open-label feasibility study. Lancet Psychiatry3: 619–627.
8.
Carhart-HarrisRGiribaldiBWattsR, et al. (2021) Trial of psilocybin versus escitalopram for depression. N Engl J Med384: 1402–1411.
9.
ColeDA (1987) Utility of confirmatory factor analysis in test validation research. J Consult Clin Psychol55: 584–594.
10.
DavisAKBarrettFSMayDG, et al. (2021) Effects of psilocybin-assisted therapy on major depressive disorder: A randomized clinical trial. JAMA Psychiatry78: 481–489.
11.
DittrichA (1975) Zusammenstellung eines Fragebogens (APZ) zur Erfassung abnormer psychischer Zustände [Construction of a questionnaire (APZ) for assessing abnormal mental states]. Z Klin Psychol Psychiatr Psychother23: 12–20.
12.
DittrichA (1985a) Ätiologie-unabhängige Strukturen veränderter Wachbewusstseinszustände. Ergebnisse empirischer Untersuchungen über Halluzinogene I. und II. Ordnung, sensorische Deprivation, Hypnagoge Zustände, Hypnotische Verfahren Sowie Reizüberflutung [Etiology-Independent Structures of Altered States of Consciousness. Results of Empirical Studies on Hallucinogens of the First and Second Order, Sensory Deprivation, Hypnagogic States, Hypnotic Procedures, and Sensory Overload]. Stuttgart, Germany: Enke.
13.
DittrichA (1985b) International study on altered states of consciousness (ISASC): Summary of the results. Ger J Psychol9: 319–339.
14.
DittrichA (1998) The standardized psychometric assessment of altered states of consciousness (ASCs) in humans. Pharmacopsychiatry31: 80–84.
15.
DittrichALamparterDMaurerM (2006) 5D-ABZ: Fragebogen zur Erfassung Aussergewöhnlicher Bewusstseinszustände. Eine kurze Einführung [5D-ASC: Questionnaire for the Assessment of Altered States of Consciousness. A Short Introduction]. Zürich: PSIN PLUS Publications.
16.
DittrichA (2010) 5D-ASC: Questionnaire for the assessment of altered states of consciousness. A short introduction. Zurich, Switzerland: PSIN PLUS.
17.
Garcia-RomeuAGriffithsRRJohnsonMW (2014) Psilocybin-occasioned mystical experiences in the treatment of tobacco addiction. Curr Drug Abuse Rev7: 157–164.
18.
GoodwinGMAaronsonSTAlvarezO, et al. (2022) Single-dose psilocybin for a treatment-resistant episode of major depression. N Engl J Med387: 1637–1648.
19.
GriffithsRRichardsWJohnsonM, et al. (2008) Mystical-type experiences occasioned by psilocybin mediate the attribution of personal meaning and spiritual significance 14 months later. J Psychopharmacol22: 621–632.
20.
GriffithsRRJohnsonMWRichardsWA, et al. (2011) Psilocybin occasioned mystical-type experiences: Immediate and persisting dose-related effects. Psychopharmacology218: 649–665.
21.
GriffithsRRJohnsonMWRichardsWA, et al. (2018) Psilocybin-occasioned mystical-type experience in combination with meditation and other spiritual practices produces enduring positive changes in psychological functioning and in trait measures of prosocial attitudes and behaviors. J Psychopharmacol32: 49–69.
22.
GrobCSDanforthALChopraGS, et al. (2011) Pilot study of psilocybin treatment for anxiety in patients with advanced-stage cancer. Arch Gen Psychiatry68:71–78.
23.
HaijenECHMKaelenMRosemanL, et al. (2018) Predicting responses to psychedelics: A prospective study. Front Pharmacol9: 897.
24.
HairJF (2016) A primer on partial least squares structural equation modeling (PLS-SEM). Thousand Oaks: SAGE Publications.
25.
HartogsohnI (2016) Set and setting, psychedelics and the placebo response: An extra-pharmacological perspective on psychopharmacology. J Psychopharmacol30: 1259–1267.
26.
HirschfeldTSchmidtTT (2021) Dose–response relationships of psilocybin-induced subjective experiences in humans. J Psychopharmacol35: 384–397.
27.
HolzeFGasserPMüllerF, et al. (2023) Lysergic acid diethylamide-assisted therapy in patients with anxiety with and without a life-threatening illness: A randomized, double-blind, placebo-controlled phase II study. Biol Psychiatry93: 215–223.
28.
HovmandORPoulsenEDArnfredS, et al. (2023a) Risk of bias in randomized clinical trials on psychedelic medicine: A systematic review. J Psychopharmacol37: 649–659.
29.
HovmandORPoulsenEDArnfredS (2023b) Assessment of the acute subjective psychedelic experience: A review of patient-reported outcome measures in clinical research on classical psychedelics. J Psychopharmacol38: 19–32.
30.
HovmandOREbbesen JensenMSøgaard JuulT, et al. (2024) Validation of the Danish Translation of the Revised Mystical Experience Questionnaire (MEQ30) and possible impact of setting, dose and intention. J Psychoactive Drugs15: 1–10.
31.
HuLBentlerPM (2009) Cutoff criteria for fit indexes in covariance structure analysis: Conventional criteria versus new alternatives. Struct Equat Model A Multidiscip J6: 1–55.
32.
KlineR (2015) Principles and practice of structural equation modeling. New York, NY: Guilford Publications.
33.
LiechtiMEDolderPCSchmidY (2017) Alterations of consciousness and mystical-type experiences after acute LSD in humans. Psychopharmacology234: 1499–1510.
34.
LimeSurvey (2012) LimeSurvey: An Open Source Survey Tool. Hamburg, Germany: LimeSurvey Project.
35.
MacleanKALeoutsakosJMJohnsonMW, et al. (2012) Factor analysis of the mystical experience questionnaire: A study of experiences occasioned by the hallucinogen psilocybin. J Sci Study Relig51: 721.
36.
MadsenMKFisherPMBurmesterD, et al. (2019) Psychedelic effects of psilocybin correlate with serotonin 2A receptor occupancy and plasma psilocin levels. Neuropsychopharmacology44: 1328–1334.
37.
MadsenMKFisherPMStenbækDS, et al. (2020) A single psilocybin dose is associated with long-term increased mindfulness, preceded by a proportional change in neocortical 5-HT2A receptor binding. Eur Neuropsychopharmacol33: 71–80.
38.
MadsenMKStenbækDSArvidssonA, et al. (2021) Psilocybin-induced changes in brain network integrity and segregation correlate with plasma psilocin level and psychedelic experience. Eur Neuropsychopharmacol50: 121–132.
39.
MorenoFAWiegandCBTaitanoEK, et al. (2006) Safety, tolerability, and efficacy of psilocybin in 9 patients with obsessive-compulsive disorder. J Clin Psychiatry67: 1735–1740.
40.
Nájera CatalánHE (2019) Reliability, population classification and weighting in multidimensional poverty measurement: A Monte Carlo study. Soc Indic Res142: 887–910.
RaisonCLSanacoraGWoolleyJ, et al. (2023) Single-dose psilocybin treatment for major depressive disorder: A randomized clinical trial. JAMA330: 843–853.
44.
RevelleWZinbargRE (2009) Coefficients alpha, beta, omega and the glb: Comments on Sijtsma. Psychometrika74: 145–154.
45.
RewelleW (2007) Psych: Procedures for psychological, psychometric, and personality research. Package for R Statistical Software. https://CRAN.R-project.org/package=psych
46.
RosemanLNuttDJCarhart-HarrisRL (2018) Quality of acute psychedelic experience predicts therapeutic efficacy of psilocybin for treatment-resistant depression. Front Pharmacol8: 974.
47.
RossSBossisAGussJ, et al. (2016) Rapid and sustained symptom reduction following psilocybin treatment for anxiety and depression in patients with life-threatening cancer: A randomized controlled trial. J Psychopharmacol30: 1165–1180.
48.
RosseelY (2012) Lavaan: An R package for structural equation modeling. J Statist Softw48: 1–36.
49.
RStudio (2019) RStudio: Integrated Development for R. Boston, MA: RStudio, Inc.
50.
SchmidL (2018) Long-lasting subjective effects of LSD in normal subjects. Psychopharmacology235: 535–545.
51.
SøndergaardAMadsenMKOzenneB, et al. (2023) Lasting increases in trait mindfulness after psilocybin correlate positively with the mystical-type experience in healthy individuals. Front Psychol13: 948729.
52.
StuderusEGammaAVollenweiderFX (2010) Psychometric evaluation of the altered states of consciousness rating scale (OAV). PLoS One5: e12412.
53.
ValleMMaquedaAERabellaM, et al. (2016) Inhibition of alpha oscillations through serotonin-2A receptor activation underlies the visual effects of ayahuasca in humans. Eur Neuropsychopharmacol26: 1161–1175.
54.
von RotzRSchindowskiEMJungwirthJ, et al. (2023) Single-dose psilocybin-assisted therapy in major depressive disorder: A placebo-controlled, double-blind, randomised clinical trial. EClinicalMedicine56: 101809.
55.
WheatonBMuthénBAlwinDF, et al. (1977) Assessing reliability and stability in panel models. Sociol Methodol8: 84–136.
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