Presentation
Search Abstracts | Symposia | Slide Sessions | Poster Sessions | Lightning Talks
Exploring Structural Impoverishment in LSD Model of Psychosis
There is a Poster PDF for this presentation, but you must be a current member or registered to attend SNL 2023 to view it. Please go to your Account Home page to register.
Poster C63 in Poster Session C, Wednesday, October 25, 10:15 am - 12:00 pm CEST, Espace Vieux-Port
This poster is part of the Sandbox Series.
Monica Chaves1, Cilene Rodrigues1, Sidarta Ribeiro2, Isabel Wießner3, Marcelo Falchi3, Luís Fernando Tófoli3; 1Pontifical Catholic University of Rio de Janeiro, 2Brain Institute, Federal University of Rio Grande do Norte, 3Interdisciplinary Cooperation for Ayahuasca Research and Outreach (ICARO), School of Medical Sciences, University of Campinas
Language abnormalities are considered biomarkers of schizophrenia and other psychotic disorders, which share similar perceptual and cognitive alterations with psychedelic experiences. It has been shown that, similar to schizophrenia, low to moderate doses of psychedelics enhance semantic association, while other evidence point towards changes in different components of language production over the time course of the acute and sub-acute LSD effects. Notwithstanding these similarities, few studies explored the language profile of neurotypicals under psychedelics. To be considered: syntax hasn’t been examined in speakers under psychedelic experience. Literature on language and schizophrenia are filled with studies characterizing anomalies at all levels of language. Recently, however, there has been strong evidence of syntactic deficits, supporting the hypothesis of language-specific deficits in schizophrenia. Accordingly, it has been argued that the inability of patients with schizophrenia to build complex propositions and coherent semantic relations between them might reflex impoverishment of grammatical knowledge. In other words, schizophrenia leads to grammatical deficits at the competence level, resulting faulty linguistic performances. It is, thus, not only important to investigate the role of language-specific deficits in schizophrenia and other psychotic disorders, but also to distinguish anomalies of the linguistic system from deficits of other cognitive resources, such as memory and attention, allowing us to tease apart impairments related to linguistic competence from those concerning linguistic performance. Our study examines linguistic variables indicative of structural deficiency (i.e., indicative of semantic, syntactic and morphological anomalies) in narratives of neurotypical individuals, native speakers of Brazilian Portuguese, under low to moderate LSD dose. The narratives under examination were previously collected by Wiessner and colleagues for the purpose of exploratory studies on the acute and subacute effect of LSD on different aspects of cognition, which adopted a randomized, double-blind, placebo-controlled, crossover design, in which 24 healthy participants, randomly assigned to treatment order, received 50μg of LSD or inactive placebo, in two treatment sessions and a washout period of 14 days between the sessions. The methodology adopted by us to analyze narratives available in Wiessner and colleagues’ corpus consists of semantic and structural analyses based on a syntactic manual annotation system, with analyses of structural complexity and semantic coherence within sentences and nominal expressions. Special attention has been given to overuse of matrix clauses and null pronouns, as markers of simpler and deficient structures, and on the anomalous use of referential pronouns, as markers of problems of linguistic reference, which have been found to be indicative of grammatical deficits in schizophrenia, and associated with the chronicity of the disorder. As we argue, the LSD model of psychosis might provide us with productive empirical grounds to distinguish impairments of linguistic competence from those of performance in psychosis.
Topic Areas: Disorders: Developmental, Language Therapy