Authors:	Schneider, Katharina Leinweber, Katrin Jamalabadi, Hamidreza Teutenberg, Lea Brosch, Katharina Pfarr, Julia-Katharina Thomas-Odenthal, Florian Usemann, Paula Wroblewski, Adrian Straube, Benjamin Alexander, Nina Nenadić, Igor Jansen, Andreas Krug, Axel Dannlowski, Udo Kircher, Tilo Nagels, Arne Stein, Frederike
Title:	Syntactic complexity and diversity of spontaneous speech production in schizophrenia spectrum and major depressive disorders
Online publication date:	24-Oct-2023
Year of first publication:	2023
Language:	english
Abstract:	Syntax, the grammatical structure of sentences, is a fundamental aspect of language. It remains debated whether reduced syntactic complexity is unique to schizophrenia spectrum disorder (SSD) or whether it is also present in major depressive disorder (MDD). Furthermore, the association of syntax (including syntactic complexity and diversity) with language-related neuropsychology and psychopathological symptoms across disorders remains unclear. Thirty-four SSD patients and thirty-eight MDD patients diagnosed according to DSM-IV-TR as well as forty healthy controls (HC) were included and tasked with describing four pictures from the Thematic Apperception Test. We analyzed the produced speech regarding its syntax delineating measures for syntactic complexity (the total number of main clauses embedding subordinate clauses) and diversity (number of different types of complex sentences). We performed cluster analysis to identify clusters based on syntax and investigated associations of syntactic, to language-related neuropsychological (verbal fluency and verbal episodic memory), and psychopathological measures (positive and negative formal thought disorder) using network analyses. Syntax in SSD was significantly reduced in comparison to MDD and HC, whereas the comparison of HC and MDD revealed no significant differences. No associations were present between speech measures and current medication, duration and severity of illness, age or sex; the single association accounted for was education. A cluster analysis resulted in four clusters with different degrees of syntax across diagnoses. Subjects with less syntax exhibited pronounced positive and negative symptoms and displayed poorer performance in executive functioning, global functioning, and verbal episodic memory. All cluster-based networks indicated varying degrees of domain-specific and cross-domain connections. Measures of syntactic complexity were closely related while syntactic diversity appeared to be a separate node outside of the syntactic network. Cross-domain associations were more salient in more complex syntactic production.
DDC:	400 Sprache 400 Language
Institution:	Johannes Gutenberg-Universität Mainz
Department:	FB 05 Philosophie und Philologie
Place:	Mainz
ROR:	https://ror.org/023b0x485
DOI:	http://doi.org/10.25358/openscience-9638
Version:	Published version
Publication type:	Zeitschriftenaufsatz
Document type specification:	Scientific article
License:	CC BY
Information on rights of use:	https://creativecommons.org/licenses/by/4.0/
Journal:	Schizophrenia 9
Pages or article number:	35
Publisher:	Springer Nature
Publisher place:	London
Issue date:	2023
ISSN:	2754-6993
Publisher DOI:	10.1038/s41537-023-00359-8
Appears in collections:	DFG-491381577-G