• wednesday, 1 april 2020—12:15

    Cancelled : Natalia Mota

    Natália B. Mota, Universidade Federal do Rio Grande do Norte

    Since the initial descriptions of psychotic syndromes, psychiatrists
    showed the importance of identifying aberrant thought organization
    through the language in order to predict clinical outcomes, such as
    cognitive loss linked to Schizophrenia (initially named “dementia
    praecox”). The description and qualification of formal thought disorder
    remained complex and subjective until the advent of computational tools
    that aim to quantify these symptoms on free speech. One strategy based
    on graph theory studied non-semantic structural features by quantifying
    spontaneous word trajectory topology. Initially, it was possible to
    characterize that dream reports from patients with schizophrenia
    diagnosis were represented by less connected graphs, and these aspects
    of language were correlated with negative symptoms. These markers were
    able to automatically identify reports from patients with schizophrenia
    diagnosis with more than 90%accuracy, even during the first clinical
    interview at the first psychotic episode. As these markers appear early
    on, it was important to understand its typical development and cognitive
    correlates. First, collecting memory reports at public schools in
    Brazil, we were able to identify a correlation of graph connectedness
    with IQ and theory of mind performances, and an independent correlation
    with reading acquisition. More, studying memory reports from more than
    200 subjects with different age (0 to 60 years old) and educational
    level (0 to 20 years of education), we could identify in typical
    subjects an asymptotic development of language graph attributes (as
    lexical diversity, connectedness and graph length increased, short-range
    recurrence decreased). These changes over time depended more on
    education than age, and the stabilization of connectedness (language
    marker of schizophrenia), required at least 13 years of education, or
    high-school level. Importantly, for atypical development (subjects that
    presented psychotic symptoms), there was no correlation of graph
    attributes with age or education, presenting at adulthood a
    children-like speech structure. Typical subject increased language
    connectedness over school years, but subjects with psychosis seem to be
    resistant to formal education, failing to mature in complexity and
    remaining to a near-random language structure. These results point to
    feasibility to search for early markers of cognitive risk in
    naturalistic settings such as school environment, enabling early
    identification and intervention to mitigate cognitive damages.

    external seminar