The recent renaissance of psychedelic science has reignited interest in the similarity of drug-induced experiences to those more commonly observed in psychiatric contexts such as the schizophrenia-spectrum. This report from a multidisciplinary working group of the International Consortium on Hallucinations Research (ICHR) addresses this issue, putting special emphasis on hallucinatory experiences. We review evidence collected at different scales of understanding, from pharmacology to brain-imaging, phenomenology and anthropology, highlighting similarities and differences between hallucinations under psychedelics and in the schizophrenia-spectrum disorders. Finally, we attempt to integrate these findings using computational approaches and conclude with recommendations for future research.

Department of Anthropology University of Durham Durham UK

Department of Applied Neurosciences and Brain Imaging National Institute of Mental Health Klecany Czechia

Department of Biological and Medical Psychology Faculty of Psychology University of Bergen Bergen Norway

Department of Psychiatry and Medical Psychology 3rd Faculty of Medicine Charles University Prague Prague Czechia

Department of Psychiatry Connecticut Mental Health Center Yale University New Haven CT

Department of Psychiatry University of California San Diego La Jolla CA

Department of Psychology Faculty of Arts Charles University Prague Czechia

Imperial College London London UK

Institut Jean Nicod École des Hautes Études en Sciences Sociales École Normale Supérieure PSL Research University Paris France

Laboratoire de Neurosciences Cognitives et Computationnelles ENS INSERM U960 PSL Research University Paris France

Norwegian Center of Excellence for Mental Disorders Research University of Oslo Oslo Norway

Pharmaco Neuroimaging and Cognitive Emotional Processing Department of Psychiatry Psychotherapy and Psychosomatics Psychiatric University Hospital Zurich University of Zurich Zurich Switzerland

Psychology and Neuroscience of Cognition Research Unit University of Liège Liège Belgium

Research Service VA San Diego Healthcare System San Diego CA

School of Psychological Sciences The University of Western Australia Perth Western Australia

Univ Lille INSERM U1172 CHU Lille Lille Neuroscience and Cognition Centre Plasticity and SubjectivitY team Lille France

Zobrazit více v PubMed

Osmond H. A review of the clinical effects of psychotomimetic agents. Ann N Y Acad Sci. 1957;66(3):418–434. PubMed

Dyck E.  Psychedelic Psychiatry  : LSD from Clinic to Campus. Baltimore, Maryland: Johns Hopkins University Press; 2008.

Hermle L, Kraehenmann R. Experimental psychosis research and schizophrenia—similarities and dissimilarities in psychopathology. In: Halberstadt AL, Vollenweider F, Nichols D, eds. Behavioral Neurobiology of Psychedelic Drugs. Current Topics in Behavioral Neurosciences. Vol 36 Berlin: Springer; 2018:313–332. PubMed

Glennon RA, Young R, Rosecrans JA. Antagonism of the effects of the hallucinogen DOM and the purported 5-HT agonist quipazine by 5-HT2 antagonists. Eur J Pharmacol. 1983;91(2–3):189–196. PubMed

Glennon RA, Titeler M, McKenney JD. Evidence for 5-HT2 involvement in the mechanism of action of hallucinogenic agents. Life Sci. 1984;35(25):2505–2511. PubMed

Canal CE, Morgan D. Head-twitch response in rodents induced by the hallucinogen 2,5-dimethoxy-4-iodoamphetamine: a comprehensive history, a re-evaluation of mechanisms, and its utility as a model. Drug Test Anal. 2012;4(7–8):556–576. PubMed PMC

Halberstadt AL, Chatha M, Klein AK, Wallach J, Brandt SD. Correlation between the potency of hallucinogens in the mouse head-twitch response assay and their behavioral and subjective effects in other species. Neuropharmacology. 2020;167:107933. PubMed PMC

Schreiber R, Brocco M, Audinot V, Gobert A, Veiga S, Millan MJ. (1-(2,5-dimethoxy-4 iodophenyl)-2-aminopropane)-induced head-twitches in the rat are mediated by 5-hydroxytryptamine (5-HT) 2A receptors: modulation by novel 5-HT2A/2C antagonists, D1 antagonists and 5-HT1A agonists. J Pharmacol Exp Ther. 1995;273(1):101–112. PubMed

Fantegrossi WE, Harrington AW, Eckler JR, et al.  Hallucinogen-like actions of 2,5-dimethoxy-4-(n)-propylthiophenethylamine (2C-T-7) in mice and rats. Psychopharmacology (Berl). 2005;181(3):496–503. PubMed

González-Maeso J, Weisstaub NV, Zhou M, et al.  Hallucinogens recruit specific cortical 5-HT(2A) receptor-mediated signaling pathways to affect behavior. Neuron. 2007;53(3):439–452. PubMed

Halberstadt AL, Geyer MA. LSD but not lisuride disrupts prepulse inhibition in rats by activating the 5-HT(2A) receptor. Psychopharmacology (Berl). 2010;208(2):179–189. PubMed PMC

Gerber R, Barbaz BJ, Martin LL, Neale R, Williams M, Liebman JM. Antagonism of L-5-hydroxytryptophan-induced head twitching in rats by lisuride: a mixed 5-hydroxytryptamine agonist-antagonist? Neurosci Lett. 1985;60(2):207–213. PubMed

Halberstadt AL, Geyer MA. Characterization of the head-twitch response induced by hallucinogens in mice: detection of the behavior based on the dynamics of head movement. Psychopharmacology (Berl). 2013;227(4):727–739. PubMed PMC

Ouagazzal A, Grottick AJ, Moreau J, Higgins GA. Effect of LSD on prepulse inhibition and spontaneous behavior in the rat. A pharmacological analysis and comparison between two rat strains. Neuropsychopharmacology. 2001;25(4):565–575. PubMed

Wing LL, Tapson GS, Geyer MA. 5HT-2 mediation of acute behavioral effects of hallucinogens in rats. Psychopharmacology (Berl). 1990;100(3):417–425. PubMed

Krebs-Thomson K, Paulus MP, Geyer MA. Effects of hallucinogens on locomotor and investigatory activity and patterns: influence of 5-HT2A and 5-HT2C receptors. Neuropsychopharmacology. 1998;18(5):339–351. PubMed

Adams LM, Geyer MA. Patterns of exploration in rats distinguish lisuride from lysergic acid diethylamide. Pharmacol Biochem Behav. 1985;23(3):461–468. PubMed

Body S, Kheramin S, Ho MY, Miranda F, Bradshaw CM, Szabadi E. Effects of a 5-HT2 receptor agonist, DOI (2,5-dimethoxy-4-iodoamphetamine), and antagonist, ketanserin, on the performance of rats on a free-operant timing schedule. Behav Pharmacol. 2003;14(8):599–607. PubMed

Asgari K, Body S, Bak VK, et al.  Effects of 5-HT2A receptor stimulation on the discrimination of durations by rats. Behav Pharmacol. 2006;17(1):51–59. PubMed

Halberstadt AL, Sindhunata IS, Scheffers K, et al.  Effect of 5-HT2A and 5-HT2C receptors on temporal discrimination by mice. Neuropharmacology. 2016;107:364–375. PubMed PMC

Vollenweider FX, Vollenweider-Scherpenhuyzen MF, Bäbler A, Vogel H, Hell D. Psilocybin induces schizophrenia-like psychosis in humans via a serotonin-2 agonist action. Neuroreport. 1998;9(17):3897–3902. PubMed

Preller KH, Herdener M, Pokorny T, et al.  The fabric of meaning and subjective effects in LSD-induced states depend on serotonin 2a receptor activation. Curr Biol. 2017;27(3):451–457. PubMed

Preller KH, Burt JB, Ji JL, et al.  Changes in global and thalamic brain connectivity in LSD-induced altered states of consciousness are attributable to the 5-HT2A receptor. Elife. 2018;7:1–31. PubMed PMC

Kraehenmann R, Pokorny D, Vollenweider L, et al.  Dreamlike effects of LSD on waking imagery in humans depend on serotonin 2A receptor activation. Psychopharmacology (Berl). 2017;234(13):2031–2046. PubMed

Madsen MK, Fisher PM, Burmester D, et al.  Psychedelic effects of psilocybin correlate with serotonin 2A receptor occupancy and plasma psilocin levels. Neuropsychopharmacology. 2019;44(7):1328–1334. PubMed PMC

Sommer IEC, Diederen KMJ, Blom JD, et al.  Auditory verbal hallucinations predominantly activate the right inferior frontal area. Brain. 2008;131(12):3169–3177. PubMed

Jardri R, Pouchet A, Pins D, Thomas P. Cortical activations during auditory verbal hallucinations in schizophrenia: a coordinate-based meta-analysis. Am J Psychiatry. 2011;168(1):73–81. PubMed

Jardri R, Thomas P, Delmaire C, Delion P, Pins D. The neurodynamic organization of modality-dependent hallucinations. Cereb Cortex. 2013;23(5):1108–1117. PubMed

Leroy A, Foucher JR, Pins D, et al.  fMRI capture of auditory hallucinations: validation of the two-steps method. Hum Brain Mapp. 2017;38(10):4966–4979. PubMed PMC

Zmigrod L, Garrison JR, Carr J, Simons JS. The neural mechanisms of hallucinations: a quantitative meta-analysis of neuroimaging studies. Neurosci Biobehav Rev. 2016;69:113–123. PubMed

Lefebvre S, Demeulemeester M, Leroy A, et al.  Network dynamics during the different stages of hallucinations in schizophrenia. Hum Brain Mapp. 2016;37(7):2571–2586. PubMed PMC

Carhart-Harris RL, Muthukumaraswamy S, Roseman L, et al.  Neural correlates of the LSD experience revealed by multimodal neuroimaging. Proc Natl Acad Sci U S A. 2016;113(17):4853–4858. PubMed PMC

Kometer M, Cahn BR, Andel D, Carter OL, Vollenweider FX. The 5-HT2A/1A agonist psilocybin disrupts modal object completion associated with visual hallucinations. Biol Psychiatry. 2011;69(5):399–406. PubMed

Kometer M, Vollenweider FX. Serotonergic hallucinogen-induced visual perceptual alterations. In: Halberstadt AL, Vollenweider FX, Nichols DE, eds. Behavioral Neurobiology of Psychedelic Drugs. Vol 36 Berlin: Springer; 2016:257–282. PubMed

Fox MD, Snyder AZ, Vincent JL, Corbetta M, Van Essen DC, Raichle ME. The human brain is intrinsically organized into dynamic, anticorrelated functional networks. Proc Natl Acad Sci U S A. 2005;102(27):9673–9678. PubMed PMC

Smith SM, Fox PT, Miller KL, et al.  Correspondence of the brain’s functional architecture during activation and rest. Proc Natl Acad Sci U S A. 2009;106(31):13040–13045. PubMed PMC

Fox MD, Zhang D, Snyder AZ, Raichle ME. The global signal and observed anticorrelated resting state brain networks. J Neurophysiol. 2009;101(6):3270–3283. PubMed PMC

Carbonell F, Bellec P, Shmuel A. Quantification of the impact of a confounding variable on functional connectivity confirms anti-correlated networks in the resting-state. Neuroimage. 2014;86:343–353. PubMed

Raichle ME. The brain’s default mode network. Annu Rev Neurosci. 2015;38:433–447. PubMed

Zhou Y, Friston KJ, Zeidman P, Chen J, Li S, Razi A. The hierarchical organization of the default, dorsal attention and salience networks in adolescents and young adults. Cereb Cortex. 2018;28(2):726–737. PubMed PMC

Alderson-Day B, Diederen K, Fernyhough C, et al.  Auditory hallucinations and the brain’s resting-state networks: findings and methodological observations. Schizophr Bull. 2016;42(5):1110–1123. PubMed PMC

Williamson P. Are anticorrelated networks in the brain relevant to schizophrenia? Schizophr Bull. 2007;33(4):994–1003. PubMed PMC

Menon V. Large-scale brain networks and psychopathology: a unifying triple network model. Trends Cogn Sci. 2011;15(10):483–506. PubMed

Menon V, Uddin LQ. Saliency, switching, attention and control: a network model of insula function. Brain Struct Funct. 2010;214(5–6):655–667. PubMed PMC

Kucyi A, Daitch A, Raccah O, et al.  Electrophysiological dynamics of antagonistic brain networks reflect attentional fluctuations. Nat Commun. 2020;11(1):325. PubMed PMC

Doll A, Sorg C, Manoliu A, et al.  Shifted intrinsic connectivity of central executive and salience network in borderline personality disorder. Front Hum Neurosci. 2013;7:727. PubMed PMC

Bolton TAW, Wotruba D, Buechler R, et al.  Triple network model dynamically revisited: lower salience network state switching in pre-psychosis. Front Physiol. 2020;11:66. PubMed PMC

Wang J, Wang Y, Wu X, et al.  Shared and specific functional connectivity alterations in unmedicated bipolar and major depressive disorders based on the triple-network model. Brain Imaging Behav. 2020;14(1):186–199. PubMed

Weng Y, Qi R, Zhang L, et al.  Disturbed effective connectivity patterns in an intrinsic triple network model are associated with posttraumatic stress disorder. Neurol Sci. 2019;40(2):339–349. PubMed

Fan J, Zhong M, Gan J, et al.  Altered connectivity within and between the default mode, central executive, and salience networks in obsessive-compulsive disorder. J Affect Disord. 2017;223:106–114. PubMed

Palaniyappan L, Liddle PF. Does the salience network play a cardinal role in psychosis? An emerging hypothesis of insular dysfunction. J Psychiatry Neurosci. 2012;37(1):17–27. PubMed PMC

Carhart-Harris RL, Erritzoe D, Williams T, et al.  Neural correlates of the psychedelic state as determined by fMRI studies with psilocybin. Proc Natl Acad Sci U S A. 2012;109(6):2138–2143. PubMed PMC

Carhart-Harris RL, Leech R, Erritzoe D, et al.  Functional connectivity measures after psilocybin inform a novel hypothesis of early psychosis. Schizophr Bull. 2013;39(6):1343–1351. PubMed PMC

Preller KH, Duerler P, Burt JB, et al.  Psilocybin induces time-dependent changes in global functional connectivity. Biol Psychiatry. 2020;88(2):197–207. PubMed

Barnett L, Muthukumaraswamy SD, Carhart-Harris RL, Seth AK. Decreased directed functional connectivity in the psychedelic state. Neuroimage. 2020;209:116462. PubMed

Carlsson M, Carlsson A. Schizophrenia: a subcortical neurotransmitter imbalance syndrome? Schizophr Bull. 1990;16(3):425–432. PubMed

Anticevic A, Cole MW, Repovs G, et al.  Characterizing thalamo-cortical disturbances in schizophrenia and bipolar illness. Cereb Cortex. 2014;24(12):3116–3130. PubMed PMC

Murray JD, Anticevic A. Toward understanding thalamocortical dysfunction in schizophrenia through computational models of neural circuit dynamics. Schizophr Res. 2017;180:70–77. PubMed PMC

Giraldo-Chica M, Woodward ND. Review of thalamocortical resting-state fMRI studies in schizophrenia. Schizophr Res. 2017;180:58–63. PubMed PMC

Preller KH, Razi A, Zeidman P, Stämpfli P, Friston KJ, Vollenweider FX. Effective connectivity changes in LSD-induced altered states of consciousness in humans. Proc Natl Acad Sci U S A. 2019;116(7):2743–2748. PubMed PMC

Müller F, Lenz C, Dolder P, et al.  Increased thalamic resting-state connectivity as a core driver of LSD-induced hallucinations. Acta Psychiatr Scand. 2017;136(6):648–657. PubMed PMC

Bauer SM, Schanda H, Karakula H, et al.  Culture and the prevalence of hallucinations in schizophrenia. Compr Psychiatry. 2011;52(3):319–325. PubMed

Waters F, Collerton D, Ffytche DH, et al.  Visual hallucinations in the psychosis spectrum and comparative information from neurodegenerative disorders and eye disease. Schizophr Bull. 2014;40(Suppl. 4):233–245. PubMed PMC

Jablensky A, Sartorius N, Ernberg G, et al.  Schizophrenia: manifestations, incidence and course in different cultures. A World Health Organization ten-country study. Psychol Med Monogr Suppl. 1992;20:1–97. PubMed

McCarthy-Jones S, Smailes D, Corvin A, et al.  Occurrence and co-occurrence of hallucinations by modality in schizophrenia-spectrum disorders. Psychiatry Res. 2017;252:154–160. PubMed

Clark ML, Waters F, Vatskalis TM, Jablensky A. On the interconnectedness and prognostic value of visual and auditory hallucinations in first-episode psychosis. Eur Psychiatry. 2017;41:122–128. PubMed

Oorschot M, Lataster T, Thewissen V, et al.  Symptomatic remission in psychosis and real-life functioning. Br J Psychiatry. 2012;201(3):215–220. PubMed

Mueser KT, Bellack AS, Brady EU. Hallucinations in schizophrenia. Acta Psychiatr Scand. 1990;82(1):26–29. PubMed

Montagnese M. et al.  A Review of Multimodal Hallucinations: Categorization, Assessment, Theoretical Perspectives, and Clinical Recommendations, Schizophrenia Bulletin,  2020. doi:10.1093/schbul/sbaa101 PubMed PMC

Dudley R, Aynsworth C, Cheetham R, McCarthy-Jones S, Collerton D. Prevalence and characteristics of multi-modal hallucinations in people with psychosis who experience visual hallucinations. Psychiatry Res. 2018;269:25–30. PubMed

Lim A, Hoek HW, Deen ML, Blom JD; GROUP Investigators Prevalence and classification of hallucinations in multiple sensory modalities in schizophrenia spectrum disorders. Schizophr Res. 2016;176(2–3):493–499. PubMed

Llorca PM, Pereira B, Jardri R, et al.  Hallucinations in schizophrenia and Parkinson’s disease: an analysis of sensory modalities involved and the repercussion on patients. Sci Rep. 2016;6:38152. PubMed PMC

Hoffman RE, Varanko M. “Seeing voices”: fused visual/auditory verbal hallucinations reported by three persons with schizophrenia-spectrum disorder. Acta Psychiatr Scand. 2006;114(4):290–2; discussion 292. PubMed

Masters REL, Houston J  The Varieties of Psychedelic Experience. New York, NY: Holt, Rinehart and Winston; 1966.

Timmermann C, Roseman L, Schartner M, et al.  Neural correlates of the DMT experience assessed with multivariate EEG. Sci Rep. 2019;9(1):16324. PubMed PMC

Strassmann R.  DMT: The Spirit Molecule. A Doctor’s Revolutionary Research into the Biology of near-Death and Mystical Experience. Rochester, VT: Park Street Press; 2001.

Studerus E, Kometer M, Hasler F, Vollenweider FX. Acute, subacute and long-term subjective effects of psilocybin in healthy humans : a pooled analysis of experimental studies. J Psychopharmacol. 2011;25(11):1434–1452. PubMed

Kluver H.  Mescal and Mechanisms of Hallucination.  Chicago, IL: University of Chicago Press; 1966.

Luke DP, Terhune DB. The induction of synaesthesia with chemical agents: a systematic review. Front Psychol. 2013;4:753. PubMed PMC

Shanon B.  The Antipodes of the Mind: Charting the Phenomenology of the Ayahuasca Experience. New York, NY: Oxford University Press; 2002.

Shulgin A, Shulgin A  TIHKAL (Tryptamines I Have Known and Loved): The Continuation. Berkeley, CA: Transform Press; 1997.

Siegel R, Jarvik M. Drug-induced hallucinations in animals and man. In: Siegel R, West L, eds. Hallucinations: Behavior, Experience and Theory. New York, NY: John Wiley; 1975:81–161.

Nayani TH, David AS. The auditory hallucination: a phenomenological survey. Psychol Med. 1996;26(1):177–189. PubMed

Handest P, Klimpke C, Raballo A, Larøi F. From thoughts to voices: understanding the development of auditory hallucinations in schizophrenia. Rev Philos Psychol. 2016;7(3):595–610.

Raballo A, Larøi F. Murmurs of thought: phenomenology of hallucinatory consciousness in impending psychosis. Psychosis. 2011;3(2):163–166.

Chadwick PD, Birchwood M. Omnipotence of voices : a cognitive approach to auditory hallucinations. Br J Psychiatry. 1994;164:190–201. PubMed

Griffiths R, Richards W, Johnson M, McCann U, Jesse R. Mystical-type experiences occasioned by psilocybin mediate the attribution of personal meaning and spiritual significance 14 months later. J Psychopharmacol. 2008;22(6):621–632. PubMed PMC

Barrett FS, Griffiths RR. Classic hallucinogens and mystical experiences: phenomenology and neural correlates. Curr Top Behav Neurosci. 2018;36:393–430. PubMed PMC

Huxley A.  The Doors of Perception and Heaven and Hell. London: Harper & Brothers; 1954.

Woods A, Jones N, Bernini M, et al.  Interdisciplinary approaches to the phenomenology of auditory verbal hallucinations. Schizophr Bull. 2014;40(Suppl. 4):S246–S254. PubMed PMC

Waters F, Allen P, Aleman A, et al.  Auditory hallucinations in schizophrenia and nonschizophrenia populations: a review and integrated model of cognitive mechanisms. Schizophr Bull. 2012;38(4):683–692. PubMed PMC

Fortier M. Sense of reality, metacognition and culture in schizophrenic and drug-induced hallucinations. In: Proust J, Fortier M, eds. Metacognitive Diversity: An Interdisciplinary Approach. Oxford: Oxford University Press; 2018:343–379.

Sanz C, Tagliazucchi E. The experience elicited by hallucinogens presents the highest similarity to dreaming within a large database of psychoactive substance reports. Front Neurosci. 2018;12:1–19. PubMed PMC

Krebs TS, Johansen PØ. Psychedelics and mental health: a population study. PLoS One. 2013;8(8):e63972. PubMed PMC

Nelson B, Sass LA. The phenomenology of the psychotic break and Huxley’s trip: substance use and the onset of psychosis. Psychopathology. 2008;41(6):346–355. PubMed

Winkelman MJ. An ontology of psychedelic entity experiences in evolutionary psychology and neurophenomenology. J Psychedelic Stud. 2018;2(1):5–23.

Dobkin de Rios M. Cultural persona in drug-induced altered states of consciousness. In: Fitzgerald TK, ed. Social and Cultural Identity. Athens: University of Georgia Press; 1974:18–19.

Furst PT.  Hallucinogens and Culture. Brand: Chandler Sharp Pub; 1976.

Hernandez F.  De Historia Plantarum Novae Hispaniae. Madrid: Ibarra; 1790.

Marquez ME.  Los Tunebo: Una Cosmogonia Recolombiana. Medellin: Editorial Copymundo; 1979.

Myerhoff BG.  Peyote Hunt: The Sacred Journey of the Huichol Indians. Ithaca, NY: Cornell University Press; 1974.

Polo de Ondegardo J. Informaciones acerca de la religio y gobierno de los Incas. In: Urteaga HH, ed. Coleccion de Libros y Documentos Referentes a La Historia Del Peru. Lima: Sanmarti y Cia; 1916:whole book.

de Sahagun B.  Historia General de Las Cosas de Nueva Espana: Libro IX. Mexico City: Editorial Pedro Robredo; 1939.

Schultes RE. Virola as an orally administered hallucinogen. Bot Mus Lealf Harv Univ. 1969;22(6):229–240.

Wasson RG. Le champignon sacré au Mexique contemporain. In: Heim R, Wasson RG, eds. Les Champignons Hallucinogènes Du Mexique. Paris: Editions du Museum; 1958:45–100.

Wright R.  Mysteries of the Jaguar Shamans of the Northwest Amazon. Lincoln, NE: University of Nebraska Press; 2013.

Reichel-Dolmatoff G.  The Shaman and the Jaguar: A Study of Narcotic Drugs among the Indians of Colombia. Philadelphia, PA: Temple University Press; 1975.

Wassen SH. The anthropological outlook for Amerindian medicinal plants. In: Swain T, ed. Plants in the Development of Modern Medicine. Cambridge, MA: Harvard University Press; 1972:1–65.

Kirchhoff P. Food-gathering tribes of the Venezuelan Llanos. In: Steward JH, ed. Handbook of South American Indians. Vol 4. Washington, DC: Smithsonian Institution; 1948:445–468.

Lumholtz C. Tarahumari dances and plant worship. Scribner’s Mag 16. 1894;16:438–456.

Kopenawa D, Albert B  The Falling Sky: Words of a Yanomami Shaman. London: Belknap Press of Harvard University Press; 2013.

Tezozomoc F.  Cronica Mexicana.  Mexico City: Jose M. Vigil; 1878.

Wallace AF. Cultural determinants of response to hallucinatory experince. AMA Arch Gen Psychiatry. 1959;1:58–69. PubMed

Mooney J. The mescal plant and ceremony. Ther Gaz. 1896;12:7–11.

Levi-Strauss C.  Structural Anthropology, Vol 2 Chicago, Illinois: University of Chicago Press; 1976.

Brown MF. From the hero’s bones: three aguaruna hallucinogens and their uses. In: Ford RI, ed. The Nature and Status of Ethnobotany. Ann-Arbor, Michigan: University of Michigan Museum of Anthropology; 1978:118–136.

Langdon EJ. Yage among the Siona: cultural patternsin visions. In: Browman D, Schwarz R, eds. Spirits, Shamans and Stars. Perspectives from South America. La Haye: De Gruyter Mouton; 1979:63–80.

Reichel-Dolmatoff G. The cultural context of an aboriginal hallucinogen: Banisteriopis Caapi. In: Furst PT, ed. Flesh of the Gods: The Ritual Use of Hallucinogens. Prospect Heights, Illinois: Waveland Press, Inc.; 1972:84–113.

Dupuis D. Apprendre a voir l’ invisible. De la pedagogie visionnaire dans un centre chamanique d’ Amazonie peruvienne. Cah d’ Anthropol Soc. 2019;17:20–42. (“Images visionnaires”).

Dupuis D. The socialization of hallucinations. Cultural priors, social interactions and contextual factors in the use of ayahuasca. Transcult Psychiatry. 2021. PubMed PMC

Noorani T, Alderson-day B. Spotlight commentary : REBUS and the anarchic brain. Neurosci Conscious. 2020;6(1):1–3. PubMed PMC

Hartogsohn I. Set and setting, psychedelics and the placebo response: an extra-pharmacological perspective on psychopharmacology. J Psychopharmacol. 2016;30(12):1259–1267. PubMed

Studerus E, Gamma A, Kometer M, Vollenweider FX. Prediction of psilocybin response in healthy volunteers. PLoS One. 2012;7(2):e30800. PubMed PMC

Kaelen M, Giribaldi B, Raine J, et al.  The hidden therapist: evidence for a central role of music in psychedelic therapy. Psychopharmacology (Berl). 2018;235(2):505–519. PubMed PMC

Carhart-Harris RL, Roseman L, Haijen E, et al.  Psychedelics and the essential importance of context. J Psychopharmacol. 2018;32(7):725–731. PubMed

Johnson M, Richards W, Griffiths R. Human hallucinogen research: guidelines for safety. J Psychopharmacol. 2008;22(6):603–620. PubMed PMC

Nuevo R, Chatterji S, Verdes E, Naidoo N, Arango C, Ayuso-Mateos JL. The continuum of psychotic symptoms in the general population: a cross-national study. Schizophr Bull. 2012;38(3):475–485. PubMed PMC

Luhrmann TM, Padmavati R, Tharoor H, Osei A. Differences in voice-hearing experiences of people with psychosis in the U.S.A., India and Ghana: interview-based study. Br J Psychiatry. 2015;206(1):41–44. PubMed

Laroi F, Luhrmann TM, Bell V, et al.  Culture and hallucinations: overview and future directions. Schizophr Bull. 2014;40(Suppl. 4):213–220. PubMed PMC

Dupuis D. Learning to control voices: comparing voice control ability during psychosis and in ritual use of ayahuasca in the Peruvian amazon. In: Alderson-Day B, Fernyhough C, Woods A. eds. Voices in Psychosis. Interdisciplinary Perspectives. Oxford: Oxford University Press; 2020. PubMed

Montague PR, Dolan RJ, Friston KJ, Dayan P. Computational psychiatry. Trends Cogn Sci. 2012;16(1):72–80. PubMed PMC

Chater N, Tenenbaum JB, Yuille A. Probabilistic models of cognition: conceptual foundations. Trends Cogn Sci. 2006;10(7):287–291. PubMed

Clark A. Whatever next? Predictive brains, situated agents, and the future of cognitive science. Behav Brain Sci. 2013;36(3):181–204. PubMed

Friston KJ, Stephan KE, Montague R, Dolan RJ. Computational psychiatry: the brain as a phantastic organ. Lancet Psychiatry. 2014;1(2):148–158. PubMed

Friston K. Hierarchical models in the brain. PLoS Comput Biol. 2008;4(11):e1000211. PubMed PMC

Spratling MW. A review of predictive coding algorithms. Brain Cogn. 2017;112:92–97. PubMed

Kalman RE. A new approach to linear filtering and prediction problems. J Basic Eng. 1960;82(Series D):35–45.

Wolpert DM, Ghahramani Z. Computational principles of movement neuroscience. Nat Neurosci. 2000;3 Suppl:1212–1217. PubMed

Friston K, Kiebel S. Predictive coding under the free-energy principle. Philos Trans R Soc Lond B Biol Sci. 2009;364(1521):1211–1221. PubMed PMC

Friston K, FitzGerald T, Rigoli F, Schwartenbeck P, Pezzulo G. Active inference: a process theory. Neural Comput. 2017;29(1):1–49. PubMed

Tschantz A, Seth AK, Buckley CL. Learning action-oriented models through active inference. PLoS Comput Biol. 2020;16(4):e1007805. PubMed PMC

Corlett PR, Frith CD, Fletcher PC. From drugs to deprivation: a Bayesian framework for understanding models of psychosis. Psychopharmacology (Berl). 2009;206(4):515–530. PubMed PMC

Friston KJ. Hallucinations and perceptual inference. Behav Brain Sci. 2005;28(6):764–766.

Benrimoh D, Parr T, Vincent P, Adams RA, Friston K. Active inference and auditory hallucinations. Comput Psychiatr. 2018;2:183–204. PubMed PMC

Corlett PR, Horga G, Fletcher PC, Alderson-Day B, Schmack K, Powers AR 3rd. Hallucinations and strong priors. Trends Cogn Sci. 2019;23(2):114–127. PubMed PMC

Powers AR, Mathys C, Corlett PR. Pavlovian conditioning-induced hallucinations result from overweighting of perceptual priors. Science. 2017;357(6351):596–600. PubMed PMC

Carhart-Harris RL, Friston KJ. REBUS and the anarchic brain: toward a unified model of the brain action of psychedelics. Pharmacol Rev. 2019;71(3):316–344. PubMed PMC

Sterzer P, Adams RA, Fletcher P, et al.  The predictive coding account of psychosis. Biol Psychiatry. 2018; 84(9):634–643. PubMed PMC

Jardri R, Denève S. Circular inferences in schizophrenia. Brain. 2013;136(Pt 11):3227–3241. PubMed

Leptourgos P, Denève S, Jardri R. Can circular inference relate the neuropathological and behavioral aspects of schizophrenia? Curr Opin Neurobiol. 2017;46:154–161. PubMed

Leptourgos P.  Dynamical circular inference in the general population and the psychosis spectrum: insights from perceptual decision making. 2018.

Jardri R, Duverne S, Litvinova AS, Denève S. Experimental evidence for circular inference in schizophrenia. Nat Commun. 2017;8:14218. PubMed PMC