Language as a Window Into the Altered State of Consciousness Elicited by Psychedelic Drugs

Abstract

Psychedelics are drugs capable of eliciting profound alterations in the subjective experience of the users, sometimes with long-lasting consequences. Because of this, psychedelic research tends to focus on human subjects, given their capacity to construct detailed narratives about the contents of their consciousness experiences. In spite of its relevance, the interaction between serotonergic psychedelics and language production is comparatively understudied in the recent literature. This review is focused on two aspects of this interaction: how the acute effects of psychedelic drugs impact on speech organization regardless of its semantic content, and how to characterize the subjective effects of psychedelic drugs by analyzing the semantic content of written retrospective reports. We show that the computational characterization of language production is capable of partially predicting the therapeutic outcome of individual experiences, relate the effects elicited by psychedelics with those associated with other altered states of consciousness, draw comparisons between the psychedelic state and the symptomatology of certain psychiatric disorders, and investigate the neurochemical profile and mechanism of action of different psychedelic drugs. We conclude that researchers studying psychedelics can considerably expand the range of their potential scientific conclusions by analyzing brief interviews obtained before, during and after the acute effects. Finally, we list a series of questions and open problems that should be addressed to further consolidate this approach.

AIT Foundations of Structured Experience

“…Additionally, as an objective measure of structured experience, we can make use of descriptive narratives in speech form. These narratives can be analyzed through state-of-the-art computational analysis, including natural language processing (NLP), to establish different metrics on text structure such as semantic coherence and speech disorganization index [Sanz et al, 2021;Tagliazucchi, 2022;Mota et al, 2017]. New methods specifically tailored to study structured experience based on syntax, entity, and sentiment analysis across S states can provide the basis for an evolution of current psychometric approaches [Dittrich, 1998;Studerus et al, 2010].…”

Acute effects of psilocybin on the dynamics of gaze fixations during visual aesthetic perception

“…We also opted to pursue this experiment under conditions that are less constrained and more natural than those of a typical lab-based study. The merits and drawbacks of this approach have been discussed with detail elsewhere (Haijen et al 2018; van Elk et al 2022; Sanz et al 2022; Tagliazucchi 2022), yet here it is important to highlight that distractions during an eye tracking task can easily introduce a large amount of missing data points, potentially rendering the gathered data useless for further analysis. This issue could be expected to become more problematic in settings where subjects can develop feelings of fear and/or anxiety, including research laboratories and hospital settings (Studerus et al 2012).…”

Quantitative Natural Language Processing Markers of Psychoactive Drug Effects: A Pre-Registered Systematic Review

“…Finally, cannabis causes speech with greater discontinuity in thought, hypothesized to be caused by cognitive effects such as intruding associations [22]. A recent review of psychedelics also highlights the value of objective analysis of language production to generate reliable markers of their psychoactive effects [23]. The quantitative features generated by the NLP analyses can enter machine learning (ML) classi ers to accurately identify if a given speech sample comes from one group (e.g., after cannabis use) or the other (no cannabis use) [19].…”