The cognitive aspect of formal thought disorder and its relationship with global social functioning and the quality of life in schizophrenia

Can neurocognitive performance account for dimensional paranoid ideation?

OBJECTIVE

Paranoid ideation underlies numerous psychological disorders and has debilitating effects on daily life. Deficits in neurocognition are highlighted as a contributing factor to paranoid-related disorders, but the impact on the symptom-level experience of paranoid ideation is unclear. This study aimed to employ a dimensional approach to understand the association between neurocognition and the severity and presence of paranoid ideation.

METHODS

400 participants, representative of the general population of the USA, completed an online questionnaire consisting of the Brief Symptom Inventory-53, and demographic and clinical questions. The participants then completed four computerised neurocognitive tasks measuring working memory, shifting, inhibition, and speed of processing.

RESULTS

Speed of processing accounted for unique variance in the severity of paranoid ideation with a small effect size, after controlling for covariates. Working memory, shifting, and inhibition could not uniquely or collectively, account for paranoid ideation. Neurocognitive performance could not distinguish between individuals with and without paranoid ideation experiences.

CONCLUSIONS

This research supports the body of literature that speed of information processing may be a key feature of paranoid ideation. Future research should employ non-linear dynamic methods to better understand the potential interactions between neurocognitive components and how this may relate to paranoid ideation.

Development and validation of a Disorganised Thoughts Scale: a new measure to assess thinking difficulties in the general population

BACKGROUND

Disordered thinking is a condition that can manifest in not only clinical cases (e.g., psychotic disorders), but also the wider general population. However, there is no current method to measure the specific cognitive processes experienced during such a condition. Therefore, this study aimed to develop a new self-report measure, the Disorganised Thoughts Scale (DTS), that can assess disorganised thinking in the general population.

METHODS

To achieve this aim, a survey was developed and shared online with four independent samples, including a sample of Australians in the general population (N = 321) and three samples (N = 200 each) that were controlled for their substance use (i.e., frequent alcohol and cannabis use; non-frequent substance use). Exploratory and confirmatory factor analyses, and reliability analyses, were used to test the internal validity, whilst correlational analyses were implemented to examine the external validity.

RESULTS

The exploratory factor analysis revealed a two-factor structure (10 items each) measuring Positive thought disorder (i.e., accelerated, uncontrollable, and incongruent thinking) and Negative thought disorder (i.e., inhibited, disjointed, and disorientated thinking). This internal structure was confirmed with subsequent confirmatory factor and reliability analyses (α = 0.90 to 0.97) in the three substance-controlled groups. Concurrent validity was also supported, as the DTS exhibited strong correlations with established measures of general cognitive difficulties, specific self-regulatory dysfunctions, and psychopathological symptomology. Finally, the measure was also shown to be significantly higher in cohorts who exhibited a higher degree of psychological distress and who frequently used substances (i.e., alcohol and cannabis).

CONCLUSIONS

Overall, this study provided preliminary evidence to suggest that the DTS is a sound measure of disorganised thought that is linked to psychopathology and substance use in non-clinical populations. The measure could be used in future research which seeks to better understand how thinking effects, and is affected by, various psychological conditions.

Semantic verbal fluency in native speakers of Turkish: a systematic review of category use, scoring metrics and normative data in healthy individuals

INTRODUCTION

Semantic verbal fluency (SVF) is a widely used measure of frontal executive function and access to semantic memory. SVF scoring metrics include the number of unique words generated, perseverations, intrusions, semantic cluster size and switching between clusters, and scores vary depending on the language the test is administered in. In this paper, we review the existing normative data for Turkish, the main metrics used for scoring SVF data in Turkish, and the most frequently used categories.

METHOD

We conducted a systematic review of peer-reviewed papers using Medline, EMBASE, PsycInfo, Web of Science, and two Turkish databases, TR-Dizin and Yok-Tez. Included papers contained data on the SVF performance of healthy adult native speakers of Turkish, and reported the categories used. Versions of the SVF that required participants to alternate categories were excluded. We extracted and tabulated demographics, descriptions of groups, metrics used, categories used, and sources of normative data. Studies were assessed for level of detail in reporting findings.

RESULTS

1400 studies were retrieved. After deduplication, abstract, full text screening, and merging of theses with their published versions, 121 studies were included. 114 studies used the semantic category "animal", followed by first names (N = 14, 12%). All studies reported word count. More complex measures were rare (perseverations: N = 12, 10%, clustering and switching: N = 5, 4%). Four of seven normative studies reported only word count, two also measured perseverations, and one reported category violations and perseverations. Two normative studies were published in English.

CONCLUSIONS

There is a lack of normative Turkish SVF data with more complex metrics, such as clustering and switching, and a lack of normative data published in English. Given the size of the Turkish diaspora, normative SVF data should include monolingual and bilingual speakers. Limitations include a restriction to key English and Turkish databases.

Narrative-Derived Indices of Metacognition among People with Schizophrenia: Associations with Self-Reported and Performance-Based Social Functioning

Metacognitive functioning-which broadly encompasses the mental processes involved in thinking about the thinking of one's self and the thinking of others-is often impaired among individuals living with schizophrenia and may contribute to difficulties in social and interpersonal functioning. Although the majority of studies assessing metacognition among individuals with schizophrenia use standardized, laboratory-based measurements, an increasing number of studies have measured metacognitive capacity using natural language produced by individuals living with mental illness. At the same time, less is known about how language-derived indices of metacognitive function relate to key social outcomes among people with schizophrenia. The primary objective of this study was to employ a validated language coding system (the Metacognition Assessment Scale, Abbreviated; MAS-A) to assess metacognitive functioning from the spoken life narratives of individuals with schizophrenia (n = 32) and community controls (n = 15). Among individuals with schizophrenia, we also examined the associations between language-derived metacognition and measures of self-reported and performance-based social functioning. Our results suggest that most aspects of metacognition in our sample were not significantly diminished in people with schizophrenia compared to community controls. Unexpectedly, the MAS-A subscale related to one's ability to master psychological difficulties was rated higher among individuals with schizophrenia. Further, our results suggest that among people with schizophrenia, higher metacognitive functioning in the domain of self-reflectivity was associated with poorer self-reported social functioning, while a greater metacognitive awareness of other individuals' minds was associated with better scores on aspects of performance-based social functioning. Collectively, these results underscore the utility of assessing metacognitive functioning via life-story narratives to understand social outcomes and highlight possible aspects of resiliency among individuals who have experienced a serious mental illness.

The relationship between psychopathology, occupational balance, and quality of life among people with schizophrenia

OBJECTIVE

There is an increased risk of occupational imbalance and poor quality of life (QoL) if one has schizophrenia. Although evidence suggests a relationship between psychopathology and QoL, the association of occupational balance (OB) with QoL in schizophrenia is unclear. This study aimed to investigate the associations among psychopathology, occupational balance, and QoL in schizophrenia.

METHODS

This was a cross-sectional study carried out in a Community Mental Health Center (CMHC). Ninety-five individuals aged 18 years or older with the diagnosis of schizophrenia participated in the study. All participants completed a sociodemographic form, Positive and Negative Syndrome Scale (PANSS), Calgary Depression Scale in Schizophrenia (CDSS), Occupational Balance Questionnaire-11 Turkish Version (OBQ11-T), and the World Health Organisation Quality of Life Assessment Instrument (WHOQOL-100-TR). Relationships among clinical and depressive symptoms, OB, and QoL variables were examined through correlation analysis, and then multiple linear regression analysis was performed to determine the variables that have influences on QOL.

RESULTS

The study participants had low OB scores and the lowest mean in the WHOQOL-social relationships subscale. WHOQOL-overall QoL score demonstrated a moderate negative correlation with the PANSS-total score and PANSS-general psychopathology subscale score (r = -0.422, r = -0.463, P < 0.001) and a mild negative correlation with the CDSS-total score (r = -0.390, P < 0.001). OBQ11-T total score showed a moderate positive correlation with the WHOQOL-overall score (r = 0.549; P < 0.001). Findings from the multiple linear regression analysis revealed that OBQ11-T (β = -0.467, P = 0.000) and PANSS-general psychopathology (β = -0.221, P = 0.045) were significant predictors of the overall QoL, explaining 48% of the variance in the overall QoL (adjusted R²  = .43, P < 0.001).

CONCLUSION

Our study findings showed that OB and general psychopathology are determinants that should be considered in improving the QoL in individuals with schizophrenia. Thereby, addressing the symptoms of general psychopathology and occupational factors to improve the QoL may be achieved with the incorporation of occupation-based programmes to routine treatment. However, further research is required.

Association between formal thought disorder and cannabis use: a systematic review and meta-analysis

Formal thought disorder (FTD) is a multidimensional syndrome mainly occurring along the psychosis continuum. Cannabis use is known to increase symptoms of psychosis, particularly positive symptoms. However, the impact of cannabis use on FTD in individuals presenting symptoms along the psychosis continuum remains unclear. To address this knowledge gap, we conducted a meta-analysis examining the association between cannabis use and FTD in those individuals. We hypothesized that cannabis would worsen FTD. We conducted a systematic search of the PubMed, ScienceDirect, PsycINFO, Web of Science, Embase and Google Scholar databases up to July 2022. The results were collated through a random-effects model using the statistical software R. Reference lists of included studies were searched for additional relevant publications. Nineteen studies were included, totalling 1840 cannabis users and 3351 non-cannabis users. The severity of FTD was found to be higher in cannabis users (SMD = 0.21, 95%CI [0.12–0.29], p = 0.00009). Subgroup analyses revealed that FTD severity was increased among cannabis users, regardless of the disorder severity: healthy individuals (SMD = 0.19, 95%CI [0.05–0.33], p = 0.02); patients with first-episode psychosis (SMD = 0.21, 95%CI [0.01–0.41], p = 0.04); patients with schizophrenia (SMD = 0.25, 95%CI [0.11–0.38], p = 0.005). Between-group differences were not significant. In line with its already known effect on positive symptoms in psychosis, cannabis use appears to be associated with increased FTD severity all along the psychosis continuum. Future research should consider potential confounding variables such as other substance use disorders and explore how FTD dimensions are impacted by cannabis use.