SynthesisFrontiers in neuroscience2021
On Perception and Consciousness in HPPD: A Systematic Review.
Synthesis in Frontiers in neuroscience, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 15 papers, 1 of them a synthesis that pooled it.
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Who cites it
15 citing papers in PubMed, 1 synthesis or guideline pooled it.
- The Diagnostic Spectrum of Sexual Hallucinations.Harvard review of psychiatryPooled it
- Ten practical suggestions for setting up a psychedelic study.Journal of psychopharmacology (Oxford, England) · 2026Article
- Characterising the clinical associations of hallucinogen persisting perception disorder: a retrospective cohort study.Translational psychiatry · 2026Article
- Flashbacks, Hallucinogen Persisting Perception Disorder (HPPD), and Reactivations Following the Use of Classic Psychedelics: Classification and Therapeutic Management.Current topics in behavioral neurosciences · 2026Review
- Psychedelic-Associated Depersonalization-Derealization Disorder.Current topics in behavioral neurosciences · 2026Review
- Pharmacological Treatment of Hallucinogen Persisting Perception Disorder (HPPD): A Systematic Review.Harvard review of psychiatry · 2025Article
- 5-MeO-DMT: An atypical psychedelic with unique pharmacology, phenomenology & risk?Psychopharmacology · 2025Review
- Naturalistic Psychedelic Use and Psychotic Symptoms: A Cross-Sectional Study of Individuals with a Personal or Family History of Psychotic or Bipolar Disorders.Psychedelic medicine (New Rochelle, N.Y.) · 2025Article
- The Psychedelic Renaissance: A Catholic Perspective.The Linacre quarterly · 2025Article
- Psychedelic iatrogenic structural dissociation: an exploratory hypothesis on dissociative risks in psychedelic use.Frontiers in psychology · 2025Article
- Neuropsychological profiles of patients suffering from hallucinogen persisting perception disorder (HPPD): A comparative analysis with psychedelic-using and non-using controls.Scientific reports · 2024Article
- Longitudinal associations between psychedelic use and unusual visual experiences in the United States and the United Kingdom.Journal of psychopharmacology (Oxford, England) · 2024Article
- Psychological effects of psychedelics in adolescents.Frontiers in child and adolescent psychiatry · 2024Article
- Perceived risk of LSD varies with age and race: evidence from 2019 United States cross-sectional data.Social psychiatry and psychiatric epidemiology · 2023Article
- Adverse effects of ayahuasca: Results from the Global Ayahuasca Survey.PLOS global public health · 2022Article
Corrections and comments
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Authors and funding
4 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Hallucinogen-persisting perception disorder (HPPD) features as a diagnostic category in the DSM-5, ICD-11, and other major classifications, but our knowledge of the phenomenology of the perceptual symptoms involved and the changes in consciousness during the characteristic "flashbacks" is limited. We systematically evaluated original case reports and case series on HPPD to define its phenomenology, associated (psycho)pathology, and course. Our search of PubMed and Embase yielded 66 relevant publications that described 97 people who, together, experienced 64 unique symptoms of HPPD. Of these, 76% concerned symptoms characteristic of Alice in Wonderland syndrome, over 50% non-visual symptoms, and 38% perceptual symptoms not clearly linked to prior intoxication states. This is in contrast with the DSM-5 diagnostic criteria for HPPD. Even though less than half of the patients showed a protracted disease course of over a year, a third achieved remission. However, in patients with co-occurring depression (with or without anxiety) HPPD symptoms persisted longer and treatment outcomes were more often negative. Thus, unlike the acute stages of psychedelic drug intoxication, which may be accompanied by altered states of consciousness, HPPD is rather characterized by changes in the
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.