Schizophrenia Research-Cognition最新文献

Distorted body representations play a major role in the onset and maintenance of Schizophrenia. However, these distortions are difficult to assess because explicit assessments can provoke intense fears about the body and require a good insight. We proposed an implicit motor imagery task to a 14-year-old girl with Early-Onset Schizophrenia. The test consisted of presenting different openings varying in width. For each aperture, the young girl has to say if she could pass through without turning her shoulders. A critical aperture is determined as the first aperture for which she considered she could no longer pass, compared to her shoulders' width. The girl perceived herself as 51 % wider than she was, indicating a significant oversized body schema. The implicit assessments of body schema generate less anxiety and does not require a great level of insight; moreover, those are promising tools for early detection of disease in prodromal phases of Schizophrenia and assistance with differential diagnosis.

Patients with schizophrenia show substantial cognitive deficits and abnormalities in neurotransmitter-related levels of mRNA in brain or peripheral blood lymphocytes. However, the relationship of cognitive deficits as measured by the MATRICS battery and mRNA levels in brain or lymphocytes has not been sufficiently explored. We measured levels of methylation or neurotransmitter-related mRNAs in lymphocytes of 38 patients with chronic schizophrenia (CSZ) and 33 non-psychotic controls (controls) by qPCR using TaqMan probes. We assessed cognitive function in these patients and controls with the MATRICS battery. We used correlation analysis and scatter plots to assess the relationship of lymphocyte mRNA levels to MATRICS domain and composite scores. CSZ subjects had a consistently negative correlation between mRNA levels in lymphocytes and MATRICS cognitive variables of speed of processing, attention-vigilance, working memory, visual learning, and overall composite score. It is uncertain whether these negative correlations represent a causative relation between specific mRNA levels and cognitive deficits. Controls had either positive correlations or non-significant correlations between mRNA and most of the MATRICS variables. There were statistically significant differences in the correlations between mRNA and MATRICS variables between CSZ vs controls for several mRNAs (DNMT1, DNMT3A, BDNF, NR3C1, FPRF3, CNTNAP2). Our data show a different relationship between mRNA levels in peripheral blood lymphocytes and MATRICS cognitive variables in CSZ vs controls. The substantive significance of these differences needs further investigation.

The aim of this study was to identify the impact of staging on a six-months transition in Ultra-High Risk (UHR) youth.

Subjects were enrolled at assessment; evolution was monitored for six months. Clinical determinants (unusual thought content, perceptual abnormalities, cognitive complaint, etc.) were collected.

37 non-psychotic and 39 UHR subjects were included. 13 UHR (35.2 %) experienced psychotic transition, while none of non-psychotic subjects did log-rank p < 0.001. Self-reported cognitive complaint was inversely associated to transition OR 0.13 95 % IC [0.03–0.64]. Unusual Thought Content was associated to psychotic transition 0R 8.57 95 % IC [1.17–63]. Self-reported cognitive complaint could be a protective transition marker in UHR.

Introduction

It is known that cognitive deficits are a core feature of schizophrenia and that in the general population, prior beliefs significantly influence learning and reasoning processes. However, the interaction of prior beliefs with cognitive deficits and their impact on performance in schizophrenia patients is still poorly understood. This study investigates the role of beliefs and cognitive variables (CVs) like working memory, associative learning, and processing speed on learning processes in individuals with schizophrenia. We hypothesize that beliefs will influence the ability to learn correct predictions and that first-episode schizophrenia patients (FEP) will show impaired learning due to cognitive deficits.

Methods

We used a predictive-learning task to examine how FEP (n = 23) and matched controls (n = 23) adjusted their decisional criteria concerning physical properties during the learning process when predicting the sinking behavior of two transparent containers filled with aluminum discs when placed in water.

Results

On accuracy, initial differences by group, trial type, and interaction effects of these variables disappeared when CVs were controlled. The differences by conditions, associated with differential beliefs about why the objects sink slower or faster, were seen in patients and controls, despite controlling the CVs' effect.

Conclusions

Differences between groups were mainly explained by CVs, proving that they play an important role than what is assumed in this type of task. However, beliefs about physical events were not affected by CVs, and beliefs affect in the same way the decisional criteria of the control or FEP patients' groups.

Background

Cognitive impairment is a widespread feature of schizophrenia, affecting nearly 80 % of patients. Prior research has linked the anticholinergic burden of psychiatric medications to these cognitive deficits. However, the impact of the anticholinergic burden from medications for physical morbidity remains underexplored. This study aimed to evaluate the anticholinergic burden of psychiatric and physical medications in patients with schizophrenia and assess its impact on cognitive function.

Methods

A total of 178 patients with schizophrenia were recruited. The assessments included an ad hoc questionnaire for collecting demographic and clinical data. Anticholinergic burden was evaluated using the cumulative Drug Burden Index (cDBI) for each participant, and cognitive function was assessed using MATRICS. Psychopathology was measured using the PANSS, CDSS, CAINS, and the CGI-S. Statistical analysis included Student's t-tests, ANOVA, Pearson correlations, and multiple linear regressions.

Results

The average cDBI was 1.3 (SD = 0.9). The model developed explained 40.80 % of the variance. The variable with the greatest weight was the cDBI (B = −11.148, p = 0.010). Negative-expression (B = -2.740, p = 0.011) and negative-experiential (B = −1.175, p = 0.030) symptoms were also associated with lower global cognitive score. However, more years of education (B = 5.140, p < 0.001) and cigarettes per day (B = 1.331, p < 0.001) predicted a better global cognitive score.

Conclusion

This study identified specific predictors of global cognition in schizophrenia, with anticholinergic burden emerging as the strongest factor. Our findings underscore the importance of considering the anticholinergic burden of treatments, in addition to negative symptoms, when designing interventions to optimize or maintain cognitive function in patients with schizophrenia.

Aberrant attentional salience has been implicated in the cannabis-psychosis association. Here, history and frequency of cannabis use were examined against changes in overshadowing (OS), a cue competition paradigm that involves salience processing. Additionally, we examined the association between OS and alternative measures of aberrant salience, as well as schizotypy, in a non-clinical adult sample.

280 participants completed an online geometry learning-based OS task, while a subset (N = 149) also completed the Salience Attribution Task (SAT) measure of aberrant salience. All completed the Schizotypal Personality Questionnaire (SPQ), Aberrant Salience Inventory (ASI), and the modified Cannabis Experience Questionnaire (CEQmv). Differences across OS and SAT performance stages and between cannabis use groups were assessed using mixed ANOVAs. Multiple regression and correlational analyses assessed the relationships between OS and SAT task metrics and SPQ and ASI subscale scores.

Current cannabis users had significantly lower OS scores during the testing phase relative to those who do not use cannabis, at medium effect sizes. Schizotypy or ASI scores did not mediate this relationship. In the SAT, current cannabis users presented significantly higher implicit aberrant salience relative to non-users. Scores in the first training phase of the OS task significantly predicted higher explicit aberrant and adaptive salience scores in the SAT.

These data indicate an association between regular cannabis use and abnormalities in cue competition effects in a healthy adult sample. Comparisons of OS and SAT cast new light on putative overlapping mechanisms underlying performance across different measures of salience.

Background

Both overweight and cognitive deficits are common among people with schizophrenia (SZ) and schizoaffective disorder. The results in earlier studies have been inconsistent on whether overweight is associated with cognitive deficits in psychotic disorders.

Aims

Our aim in this study was to detect possible associations between obesity and cognitive deficits among study participants with SZ and schizoaffective disorder.

Methods

The study sample included 5382 participants with a clinical diagnosis of SZ or schizoaffective disorder selected from the Finnish SUPER study. Obesity was measured both with body-mass index and waist circumference. The cognitive performance was evaluated with two tests from the Cambridge automated neuropsychological test battery: Reaction time was evaluated with the 5-choice serial reaction time task. Visual memory was evaluated with the paired associative learning test. The final analysis included a total sample of 4498 participants applicable for the analysis of the reaction time and 3967 participants for the analysis of the visual memory.

Results

Obesity measured with body-mass index was associated with better performance in reaction time task among both female and male participants. Among male participants, overweight was associated with better performance in the visual memory test. The waist circumference was not associated with cognitive measures.

Conclusions

The results suggest that obesity in people with SZ or schizoaffective disorder might not be associated with cognitive deficits but instead with better cognitive performance. The results were opposite from earlier literature on the general population. More research is required to better understand whether the results might be partly caused by the differences in the etiology of obesity between the general population and people with SZ.

Schizophrenia spectrum disorders (SSD) are associated with pervasive cognitive impairments, including deficits in decision-making under risk. However, there is inconclusive evidence regarding specific mechanisms underlying altered decision-making patterns. In this study, participants (33 SSD and 28 non-SSD) completed the Columbia Card Task, an explicit risk-taking task, to better understand risk preference and adjustment in dynamic decision-making. We found that while there is no group difference in overall risk-taking, risk preference, or optimal decision-making, risk adjustment to contextual factors (e.g., loss probability) is blunted in SSD. We also found associations between risk-taking/suboptimal decision-making and disorganized symptoms, excited symptoms, and role functioning, but no associations between decision-making and working memory. These results suggest that during a complex, dynamic risk-taking task, individuals with SSD exhibit less adaption to changing information about risk, which may reflect risk imperception.

While cognitive remediation therapy (CRT) and compensatory strategy training both have large literature bases supporting their efficacy on both proximal and distal outcomes, the research base on stand-alone cognitive training (CT) is smaller and less consistent, with little information about factors associated with better outcomes. In this study, we examined the efficacy of CT on training task, cognitive, symptom, and functional ability measures as well as the impact of motivational interviewing (MI), motivation level, and session attendance on treatment outcomes. Adults with psychotic spectrum disorders (n = 114) were randomized to MI or a sham control interview (CI), followed by 4 months of computerized CT. In whole sample analyses, participants improved on training tasks, cognitive performance, and psychiatric symptoms, but self-reported cognition, self-reported depression, and functional ability did not change. Compared to CI, MI was associated with greater reductions in self-reported depressive symptoms. Motivation level and session attendance did not significantly influence outcomes. Findings support the efficacy of CT on several key outcomes, and its simplicity may be advantageous in uptake in community clinics with limited staffing. The lack of functional gains underscores the need to incorporate treatment ingredients that promote generalization and real-world implementation of learned skills. We also speculate that engagement during course of training may be a better predictor of training success than baseline task-specific motivation.