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altered states of consciousness
Also known as: ASCs, HASC, altered state of consciousness, Alternate states of consciousness, modified states of consciousness
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Classification Schemes of Altered States of Consciousness - ORBi orbi.uliege.be 21 facts
referenceSchmidt and Berkemeyer (2018) published 'The altered states database: psychometric data of altered states of consciousness,' which provides psychometric data regarding altered states of consciousness.
referenceAdolf Dittrich published empirical research in 1985 titled 'Atiologie-unabhängige Strukturen veränderter Wachbewusstseinszustände', which examines etiology-independent structures of altered states of consciousness, including hallucinogens, sensory deprivation, hypnagogic states, hypnotic procedures, and sensory overload.
referenceGlicksohn, J. published 'Altered sensory environments, altered states of consciousness and altered-state cognition' in The Journal of Mind and Behavior, volume 14, issue 1, pages 1–11, in 1993.
referenceErika Fromm published 'An ego-psychological theory of altered states of consciousness' in the International Journal of Clinical and Experimental Hypnosis in 1977.
referenceThe Altered Xperience Project (AXP) provides quantitative and qualitative data regarding the subjective experience of altered states of consciousness, as detailed in a 2023 study by Schmidt, T.T., Costines, C., Tagliazucchi, E., Millière, R., Garrido, J.M., and Cuiule, J.I.
claimBeischel, Rock, and Krippner (n.d.) conducted a 50-year retrospective on the field of altered consciousness.
referenceH. Evans authored the book 'Alternate states of consciousness', published by Aquarian Press in Wellingborough, England, in 1989.
referenceThe 'Phenomenoconnectomics' study by Timo Torsten Schmidt and Georg Fejer (2021) investigates neural correlates of altered states of consciousness.
referenceGlicksohn, J. published 'The induction of an altered state of consciousness as a function of sensory environment and experience seeking' in Personality and Individual Differences, volume 12, issue 10, pages 1057–1066, in 1991.
referenceJ. Prugger, E. Derdiyok, J. Dinkelacker, C. Costines, and T.T. Schmidt published 'The Altered States Database: Psychometric data from a systematic literature review' in 2022, which provides psychometric data on altered states of consciousness.
referenceAldous Huxley authored 'The Doors of Perception and Heaven and Hell', which explores altered states of consciousness.
claimClassification schemes for altered states of consciousness (ASCs) are categorized into three groups based on their criteria: (1) state-based schemes, which use the nature, variety, and intensity of subjective experiences including conceptual descriptions and psychometric assessments; (2) method-based schemes, which use the technique of induction; and (3) neuro/physio-based schemes, which describe neurophysiological mechanisms.
referenceHruby et al. (2024) found that the induction of altered states of consciousness during Floatation-REST (Restricted Environmental Stimulation Technique) is associated with the dissolution of body boundaries and the distortion of subjective time, published in Scientific Reports.
referenceC. Freitas, A.M. Mendes, and S. Queirós published 'The role of modified states of consciousness in druguse' in European Psychiatry in 2016.
referenceWittmann, M. (2018) published 'Altered States of Consciousness: Experiences Out of Time and Self' through MIT Press, which explores the phenomenology of altered states.
referenceM. Havenith et al. published a study in 2025 finding that decreased CO2 saturation during circular breathwork supports the emergence of altered states of consciousness.
referenceCofré et al. published 'Whole-brain models to explore altered states of consciousness from the bottom up' in Brain Sciences in 2020, proposing a bottom-up modeling approach to study altered states of consciousness.
referenceSchmidt, T.T. and Prein, J.C. (2019) characterized the Ganzfeld experience as a stably inducible altered state of consciousness and studied the effects of different auditory homogenizations on it.
referenceAdam J. Rock and Stanley Krippner published 'Does the concept of “altered states of consciousness” rest on a mistake?' in 2007, questioning the validity of the concept of altered states of consciousness.
referenceBodmer, Dittrich, and Lamparter authored 'Aussergewöhnliche Bewusstseinszustände - Ihre gemeinsame Struktur und Messung' (Altered states of consciousness: Their common structure and assessment), published in the 1994 collection 'Welten des Bewusstseins, Bd. 3' edited by Hofmann and Leuner.
referenceArnold M. Ludwig published a seminal paper titled 'Altered states of consciousness' in the Archives of General Psychiatry in 1966.
Altered State of Consciousness | Springer Nature Link link.springer.com Sep 17, 2025 14 facts
referenceJ. Shear authored 'Eastern approaches to altered states of consciousness' in the 2011 book 'Altering consciousness. volume 1: Multidisciplinary perspectives'.
claimAltered states of consciousness can be triggered by activities, drugs, mental health issues, or spontaneous events such as daydreaming or sleeping.
referenceT. Schmidt and T. Majic published 'Empirische Untersuchung Veränderter Bewusstseinszustände' (Empirical investigation of altered states of consciousness) in the 2016 book 'Handbuch Psychoaktive Substanzen'.
claimNearly all human societies engage in practices that lead to altered states of consciousness, though the methods, functions, and cultural contexts of these practices vary widely.
referenceBeyerstein, B. (1996) authored the entry 'Altered states of consciousness' in 'The encyclopedia of the paranormal', edited by G. Stein.
claimAltered states of consciousness (ASCs) are defined as situations that deviate considerably from regular waking awareness.
referenceBundzen, P. V., Korotkov, K. G., & Unestahl, L. E. (2002) published 'Altered states of consciousness: Review of experimental data obtained with a multiple techniques approach' in the Journal of Alternative and Complementary Medicine.
claimAltered states of consciousness can be induced by hypnosis, meditation, and psychoactive medications, or occur naturally through sleep and dreaming.
claimCross-cultural research indicates that a major variation in practices leading to altered states of consciousness is whether societies believe in possession by spirits or in the soul fleeing or going on a journey.
referenceC. T. Tart published 'Altered states of consciousness: A book of readings' through Wiley in 1969.
referenceA. Revonsuo, S. Kallio, and P. Sikka published 'What is an altered state of consciousness?' in Philosophical Psychology in 2009.
referenceAvner, J. R. (2006) published 'Altered states of consciousness' in the journal Pediatrics in Review.
referenceThe entry titled 'Altered State of Consciousness' is published in the 'Encyclopedia of Religious Psychology and Behavior', edited by T.K. Shackelford and published by Springer in Cham.
claimEdwards, Harris, and Biersner (1976) investigated the encoding and decoding of connected discourse during altered states of consciousness.
The Mechanisms of Psychedelic Visionary Experiences - Frontiers frontiersin.org Sep 27, 2017 13 facts
claimThe similarity between phenomenal experiences produced by psychedelics and other altered states of consciousness suggests that a biological model is necessary to explain their causation.
claimCorrelations between scales of mystical experience and altered states of consciousness with changes in brain connectivity during psychedelic sessions suggest the neurological mechanisms producing these phenomenal experiences.
claimPsychedelics are associated with experiences of the supernatural, including the separation of one's soul or spirit from the body and its travel to the supernatural world, which are signature experiences of altered consciousness in shamanism.
accountThe International Study on Altered States of Consciousness (ISASC), conducted by Dittrich, von Arx, and Staub in 1985, provided a summary of results regarding altered states of consciousness.
referenceVaitl et al. published 'Psychobiology of altered states of consciousness' in Psychological Bulletin in 2005 (Psychol. Bull. 131, 98–127).
claimThe transient hypofrontality hypothesis, proposed by Arne Dietrich in 2003, provides a functional neuroanatomical explanation for altered states of consciousness.
referenceResearch projects, such as the review by Preller and Vollenweider (2016), provide converging findings that confirm the empirical nature of altered states of consciousness.
claimVaitl et al. (2005) attribute the general causes of alterations of consciousness to compromised brain structures, disconnectivity in brain dynamics between distributed brain regions, or imbalances in neurochemical and metabolic processes.
claimAlterations of consciousness can be achieved through diverse means, including psychological, physical, and physiological stimulation, as well as disease.
claimMany alterations of consciousness involve temporally disconnected oscillatory activity of the thalamocortical circuits or defective connectivity between distributed brain regions, which results in the emergence of activity in ascending thalamocortical systems and produces hallucinatory experiences.
claimDietrich (2003) proposed that the alteration of consciousness through the disruption of normal control processes is associated with endurance running, dreaming, hypnosis, drug-induced states, and meditation, due to the deregulation of higher-order functions of the prefrontal cortex.
claimThe interruption of the Default Mode Network (specifically the posterior cingulate cortex) by meditation, hypnosis, and epilepsy necessitates a general explanation for psychedelic effects within the broader context of altered consciousness.
claimPsychedelics and other alterations of consciousness elicit many of the ten innate human intelligence modules, though not all are equally affected.
Psychedelics, Sociality, and Human Evolution frontiersin.org 10 facts
referenceHorváth, Szummer, and Szabo published 'Weak phantasy and visionary phantasy: the phenomenological significance of altered states of consciousness' in Phenomenology and the Cognitive Sciences in 2017.
perspectivePsychedelic use may have declined in modern human societies because safer, more effective, or more convenient methods to access altered states of consciousness and support social bonding—such as music and religion—have become integral parts of the human niche.
claimThe niche-construction dynamic, involving a combination of cultural and biological selection, explains why psychedelic use is not ubiquitous while institutionalized altered states of consciousness, music, and religion are cross-cultural universals.
claimMagico-religious activities in ancestral human populations utilized dancing, singing, and enactment to induce alterations of consciousness, which served to enhance peace-making, social affiliation, and imagination during community-wide nighttime healing and social effervescence rituals.
referencePreller et al. (2019) published 'Effective connectivity changes in LSD-induced altered states of consciousness in humans' in PNAS, detailing how LSD impacts brain connectivity and consciousness.
claimMythological narratives and religious beliefs were developed to enable individual integration and collective accommodation of the profound and often unsettling visionary experiences encountered during altered states of consciousness.
referenceE. Bourguignon authored 'Religion, Altered States of Consciousness, and Social Change', published by Ohio State University Press in 1973.
claimRitual chanting, music, and dance were developed to induce euphoria and ecstasy, known as altered states of consciousness (ASC), which enhance health, well-being, social bonding, and creativity even without the ingestion of psychedelics.
claimThe construction of the socio-cognitive niche in ancestral human populations involved the expansion of informal religious activities or 'wild traditions' that featured leaders with supernatural qualities, such as shamans, who ritually induced altered states of consciousness to provide healing and divination services.
claimHumans are unique in their intentional and periodic self-administration of psychoactive compounds within the context of shared intentionality, such as ritual or dance, and their use of non-pharmacological techniques to induce altered states of consciousness (ASC).
Psychedelics and Consciousness: Distinctions, Demarcations, and ... ouci.dntb.gov.ua 6 facts
referenceTart authored the book 'Altered States of Consciousness,' which examines various states of consciousness.
claimKatrin Preller et al. found that changes in global and thalamic brain connectivity during LSD-induced altered states of consciousness are attributable to the 5-HT2A receptor, as published in eLife, volume 7, article e35082.
referenceDittrich developed the 5D-ASC questionnaire for the assessment of altered states of consciousness.
claimSerotonergic psychedelics induce altered states of consciousness and have shown potential for treating neuropsychiatric disorders, including depression and addiction.
referenceCofré et al. utilized whole-brain models to explore altered states of consciousness from a bottom-up perspective, as published in Brain Sciences (2020).
claimKatrin Preller et al. studied effective connectivity changes in LSD-induced altered states of consciousness in humans, published in the Proceedings of the National Academy of Sciences of the United States of America, volume 116, page 2743.
The Montreal model: an integrative biomedical-psychedelic ... frontiersin.org 5 facts
measurementThe Montreal model's six intravenous ketamine treatments provide patients with a similar amount of time in an altered state of consciousness as two doses of psilocybin.
claimThe use of calm, de-medicalized rooms reduces the distress associated with altered states of consciousness induced by serotonergic psychedelics and esketamine.
claimThe Montreal model of ketamine treatment spreads the total duration of altered states of consciousness over 4 weeks, whereas psilocybin treatment typically occurs over one or two sessions.
measurementThe Montreal model's six ketamine treatments yield approximately the same amount of time in an altered state of consciousness as 12 psilocybin treatments, but spread out over multiple sessions.
referenceA. Dittrich published 'The standardized psychometric assessment of altered states of consciousness (ASCs) in humans' in Pharmacopsychiatry in 1998.
Altered states of consciousness – Knowledge and References taylorandfrancis.com 5 facts
claimParticipants in ritually induced altered states of consciousness and trance states often regard the experience positively, sometimes attributing the experience to a privileged contact with the supernatural, such as observed among Pentecostals.
claimPsychedelic use carries a risk of harm to self and others, including lethal harm, while the user is in an altered state of consciousness.
referenceAnthropological accounts of altered states of consciousness induced by ritual suggest a two-part distinction in ways of experiencing, similar to the distinction found in hypnosis research (Cardeña, 1996).
claimAltered states of consciousness occurring during religious ceremonies or spiritual practices, such as speaking in tongues, religious conversion experiences, shamanic visions, spirit possession, or yogic meditation, are typically highly motivated and sought-after experiences.
claimAyahuasca induces an altered state of consciousness that is difficult to compare and describe due to its abstract character, with the most commonly reported subjective effects being introspection, serenity, biographical memories, sensations of well-being, hallucinations, synaesthesia (specifically visual and auditory), and mystical or religious experiences.
A Synergistic Workspace for Human Consciousness Revealed by ... elifesciences.org 3 facts
referenceThe paper 'Dynamic functional connectivity and brain metastability during altered states of consciousness' was published in NeuroImage in 2018.
referenceThe study 'Modeling an auditory stimulated brain under altered states of consciousness using the generalized ising model' was published in NeuroImage (volume 223) in 2020.
referenceThe study 'Quantifying arousal and awareness in altered states of consciousness using interpretable deep learning' published in Nature Communications presents a method for quantifying arousal and awareness in altered states of consciousness using interpretable deep learning.
Altered States of Consciousness . A Comparative Review of the ... semanticscholar.org 2 facts
perspectiveThe authors of 'Altered States of Consciousness . A Comparative Review of the ...' assert that more detailed scientific research is required to understand altered states of consciousness induced by hallucinogens (H-ASC).
claimAltered states of consciousness induced by hallucinogens (H-ASC) are considered a vaguely understood phenomenon in the paper 'Altered States of Consciousness . A Comparative Review of the ...'.
Neuroimaging in psychedelic drug development: past, present, and ... nature.com Sep 27, 2023 2 facts
referenceVollenweider and Geyer (2001) published a systems model of altered consciousness in Brain Research Bulletin, integrating natural and drug-induced psychoses.
referenceK.H. Preller, J.B. Burt, J.L. Ji, C.H. Schleifer, B.D. Adkinson, P. Stämpfli, et al. published 'Changes in global and thalamic brain connectivity in LSD-induced altered states of consciousness are attributable to the 5-HT2A receptor' in the journal eLife in 2018.
Classification schemes of altered states of consciousness sciencedirect.com 1 fact
referenceThe authors of the paper 'Classification schemes of altered states of consciousness' review prominent classification schemes that have been proposed to introduce systematicity into the scientific study of altered states of consciousness (ASCs).
Unknown source 1 fact
referenceThe academic paper titled 'Altered states of consciousness: Review of experimental data obtained with psychedelics' was published in the journal Pharmacological Reviews, volume 71, issue 3, pages 316–344.
Awake or Sleeping? Maybe Both… A Review of Sleep ... - PMC pmc.ncbi.nlm.nih.gov Jun 6, 2023 1 fact
claimThe authors of the article 'Awake or Sleeping? Maybe Both… A Review of Sleep' classify sleep-related dissociative states into three categories: physiological states, pathological states, and altered states of consciousness.
A consensus taxonomy of altered (nonordinary) states of ... psycnet.apa.org Jun 12, 2025 1 fact
referenceThe article 'A consensus taxonomy of altered (nonordinary) states of ...' presents a taxonomy of altered states of consciousness that is primarily based on their central phenomenological features.
Ancient Roots of Today's Emerging Renaissance in ... link.springer.com 1 fact
claimLSD-induced altered states of consciousness are attributable to the 5-HT2A receptor, according to a 2018 study by Katrin Preller et al.
Hallucinatory Altered States of Consciousness as Virtual Realities ... researchgate.net 1 fact
referenceThe doctoral thesis titled "Hallucinatory Altered States of Consciousness as Virtual Realities" investigates altered states of consciousness (ASC) that are marked by hallucinations and those that occur during hypnosis.
the consumption of psychoactive plants in ancient global and ... academia.edu 1 fact
referenceH.U. Sayin published the article "Altered states of consciousness occurring during expanded sexual response in the human female: preliminary definitions" in the journal NeuroQuantology in 2011, volume 9, issue 4, pages 882-891.
Published Studies — Johns Hopkins Center for Psychedelic and ... hopkinspsychedelic.org 1 fact
referenceA 2025 paper published in Psychology of Consciousness: Theory, Research, and Practice by Cardeña et al. proposes a consensus taxonomy for altered (nonordinary) states of consciousness.
Effects of psychedelics on neurogenesis and broader neuroplasticity link.springer.com Dec 19, 2024 1 fact
claimPsychoactive tryptamines induce altered states of consciousness characterized by heightened introspection (de Araujo et al. 2012) and changes in sensory perception, mood, and thought (Calvey and Howells 2018).
Psychoactive Plants Consumed in Religious Rituals: Common ... researchgate.net Feb 1, 2019 1 fact
claimPsychoactive plants contain hallucinogenic molecules that induce a form of altered states of consciousness, referred to as HASC.
Classification Schemes of Altered States of Consciousness researchgate.net Nov 4, 2025 1 fact
claimThere has been a renewed interest in the conceptual and empirical study of altered states of consciousness in recent years.
Recent Advances in the Study of Altered State of Consciousness mdpi.com 1 fact
claimThe Special Issue of the journal Brain Sciences titled 'Recent Advances in the Study of Altered State of Consciousness' aims to provide an overview of recent advances in understanding the neural correlates of conscious awareness and altered states of consciousness.