Schizophrenia (Heidelberg, Germany)最新文献

Brain activity undergoes intrinsic fluctuations with complexities specific to both the resting state and the task state. However, in patients with schizophrenia (SZ), where the boundary between internal and external realms is blurred, optimal modulation of these complexities between rest and stimulus phases is likely disrupted. Here, we present a frequency-dependent rest-task shift in electroencephalography (EEG) complexity in normal controls (NCs) and the associated abnormal patterns in patients with SZ. Specifically, we examined EEG complexity in different frequency bands, quantified by multiscale entropy (MSE), during the resting state and a 40 Hz auditory steady-state response (ASSR) task in 77 normal controls (NCs) and 103 patients with SZ. We compared the ASSR/resting MSE ratio between the NC and SZ groups. In the NC group, transitioning from the resting state to the ASSR state caused increased alpha-band entropy and decreased gamma-band entropy, whereas no such shifts were observed in patients with SZ. This study suggests that in NCs, alpha-band oscillatory complexity, which influences cortical response properties, increases during the transition from intrinsic to extrinsic information processing, while gamma-band oscillatory complexity decreases, likely due to concentration on auditory processing of a temporal enriching stimulation with high salience. Patients with SZ, which are marked by impaired neural synchrony, lacked the NCs' pronounced changes in neural complexity across frequency bands. This indicates that in patients with SZ, disruptions in the spontaneous activity that shapes the internal mental state may alter the properties of cortical responses and entrainment to external stimuli.

The default position in the treatment of psychotic conditions is that lifelong treatment is required after multiple episodes, with some portion of patients able to stop after a single episode. However, there are reasons to question this consensus, including that not everyone who stops antipsychotics relapses, the protective effects of antipsychotics may have been exaggerated due to the possibility that withdrawal itself is associated with adverse effects, including relapse, there is little evidence that antipsychotics target a pathological mechanism and their adverse effects may outweigh their benefits for some users. Recent pragmatic trials that employ a gradual reduction strategy give mixed results. They highlight that relapse is still a potential risk, but there may be gains in terms of social functioning in the long-term. There are no consistent factors that enable identification of people who might be able to discontinue antipsychotics more successfully, suggesting this option should be more widely offered. A gradual, hyperbolic approach to tapering has been proposed to reduce the adverse effects of withdrawal and relapse on stopping-approximated, for example, by reductions of 5-10% of the most recent dose every month. Patients should be supported to make decisions about long-term antipsychotic treatment based on weighing up the pros and cons of antipsychotic effects, in the light of the evidence base and the individual's priorities. Given that increasing duration of treatment is likely to increase the risk of withdrawal on stopping, long-term antipsychotic treatment should be minimized where possible.

Fundamental to coherence in discourse is referential structure - identifying entities through noun phrases (NPs, e.g. a man; that large cat) and tracking them in discourse. But coherence is also mediated by conceptual-semantic structure, as tracked through semantic similarity relations between words, and by predictability ("perplexity"). Alterations in speech coherence have long been noted in schizophrenia spectrum disorders (SSD) along all three of these dimensions. These are likely connected, but have largely been studied in isolation. This study targeted them together, in Turkish-speaking people with a first episode of psychosis (FEP, n = 53), youths at ultra-high risk (UHR, n = 64) of SSD, people with a family history of psychosis (FHP, N = 39), and 34 neurotypical controls (NC). In FEP, we confirmed a pattern previously attested in chronic SSD, of fewer definite NPs (e.g., this bald man), more "bare" NPs-i.e., lacking functional elements such as this/a -, and an unexpected random distribution of indefinite NPs; moreover, referential anomalies (unclarities of reference) were more prevalent in all groups relative to NC. FEP and UHR also showed higher word-to-word semantic similarity, and FEP larger image-to-text bimodal semantic distance, mirroring a pattern previously attested in English. NP-related variables related to both semantic similarity and perplexity, with crucially different correlational patterns seen for definite vs. indefinite NPs. Together, these results substantiate crosslinguistic evidence of a referential disturbance in early psychosis, partially extending to the extended schizophrenia phenotype, while additionally supporting that referential structure is closely integrated with conceptual semantics and the probabilistic structure of speech.

Metabolic syndrome (MetS) and diabetes mellitus (DM) are frequent in schizophrenia (SCZ) and have been linked to cognitive impairment and low-grade inflammation. In this cross-sectional study of adults with DSM-5 SCZ (N = 218; SCZ = 103, SCZ+MetS = 62, SCZ + DM = 53), we quantified interleukine-6 (IL-6) and C-Reactive Protein (CRP) and evaluated their associations with Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) cognitive domains and routine metabolic measures using multivariable models. Results revealed that SCZ + DM showed lower attention and delayed memory scores than SCZ and SCZ+MetS. No between-group differences were observed for immediate memory, visuospatial function, or language. IL-6 was highest in SCZ + DM, intermediate in SCZ + MetS, and lowest in SCZ. CRP did not differ significantly between groups. Across the cohort, higher IL-6 and fasting glucose were associated with lower attention and delayed memory. We conclude that DM status and higher IL-6 were most consistently associated with poorer attention and delayed memory in SCZ. Given the cross-sectional design, these findings reflect associations and may be influenced by treatment and residual confounding. Longitudinal studies with broader cytokine panels are warranted.

Measuring Formal Thought Disorder (FTD), a common, cross-diagnosed symptom dimension across mental disorders, is plagued by numerous inconsistencies. Clinicians use either FTD-specific scales or items from generic scales. While these tools are based on extensive clinical observations, they suffer from inconsistent terminology. Different scales may use the same term for distinct concepts or different terms for the same concept. This lack of conceptual standardization prevents the identification of underlying FTD subconstructs. By using natural language processing, we compared the definitions, labeling and overlap of FTD symptoms, i.e., the definitions of single items, across psychopathological scales. We used a three-pronged validation approach to analyze semantic clusters of single definitions of FTD scale psychopathological items. First, we used sentence-BERT to divide 30 Thought and Language Disorder scale (TALD) items into positive or negative FTD clusters, validating this approach by checking for correspondence with published factor-analytic divisions (approach validation). Second, we created a sparse item-to-item similarity matrix from 103 items across seven scales to identify semantically converging cross-scale FTD items; a clinician-researcher described the resulting four clusters, and we compared our automated classification with that of six blinded experts to establish expert-machine semantic correspondence. Finally, we analyzed data from 98 participants (49 healthy controls and 49 schizophrenia/affective psychosis), identifying the highest-correlating Clinical Language Disorder Scale (CLANG) item for each Thought, Language and Communication (TLC) scale item and mapping these to our BERT-derived clusters to establish data-level correspondence. When assigning TALD items to BERT-derived positive or negative FTD groupings, we observed a 73% match with prior factor analyses. The BERT-informed clustering of cross-scale items highlighted four coherent FTD groupings: (1) muddled communication & incomprehension, (2) abrupt topic shifts, (3) inconsistent narrative structure, (4) restricted speech. Expert raters showed moderate-to-high overlap (Fleiss' kappa = 0.617) with computational clusters. A binomial test indicated that at the level of individual participants, correlations among CLANG-TLC item pairs were significantly more likely than chance to fall into the expected semantic cluster (p < 0.001). FTD rating scales measure overlapping, semantically related constructs that drive item-level correlations. Semantic clustering acts as a novel method to harmonize multi-scale data and pinpoint discrepancies between expert and machine classifications. Computational linguistics has the potential to improve consistency across rating scales especially when measuring complex constructs such as FTD.