Neuroscience and biobehavioral reviews
August 1, 2025
Larry Douglas Fort, Cyril Costines, Marc Wittmann et al.
14 citations
A review of classification schemes for altered states of consciousness (ASCs) groups them into three types: those based on subjective experiences (state-based), those based on induction methods (method-based), and those based on neurophysiological mechanisms (neuro/physio-based). Comparing and extending these schemes can improve identification of neural correlates of consciousness and inform clinical research. The authors cluster concepts from state-based schemes to help quantify core ASC phenomenology for basic and clinical studies.
Current topics in behavioral neurosciences
December 31, 2024
Cyril Costines, Timo Torsten Schmidt
8 citations
Psychedelic substances produce a wide range of effects on perception, cognition, and emotion, collectively called "psychedelic phenomenology." There is no agreement on which altered features, such as hallucinations or ego dissolution, define a "psychedelic state." This chapter reviews commonly discussed core features of psychedelic experiences, focusing on recent quantitative assessment methods rather than earlier phenomenological work. It also addresses under-researched distressing effects, or "challenging experiences" ("bad trips"), highlighting their importance for understanding therapeutic potential and risks. Historically, psychedelic phenomenology links to psychopathology. Refining assessment of distressing effects is stressed to identify factors promoting beneficial acute experiences and limiting potentially harmful long-term effects.
June 4, 2023
Timo Torsten Schmidt, Cyril Costines, Enzo Tagliazucchi et al.
2 citations
preprint
The Altered Xperience Project (AXP) is an open citizen science initiative that systematically collects data on subjective experiences from consciousness-manipulating techniques, including psychoactive substances and non-pharmacological methods. A proof-of-principle dataset (v1.0) includes data collected through May 2022, with most gathered between October 3 and 13, 2022. The dataset covers low, medium, and high doses of alcohol, cannabis, NMDA, and psilocybin. Participants were recruited internationally via social media by the citizen science group El gato y la Caja, and participation was incentivized with an infographic comparing individual data to others. The data is publicly available on the Open Science Framework.