The Chinese Brief Cognitive Test: Normative Data Stratified by Gender, Age and Education

Interaction between serum inflammatory cytokines and brain-derived neurotrophic factor in cognitive function among first-episode schizophrenia patients

BACKGROUND

The pathogenesis of cognitive impairment in schizophrenia (SCZ) remains unclear. Accumulating studies showed that inflammatory-immune dysregulation and altered brain derived neurotrophic factor (BDNF) levels play a crucial role in the psychopathology of SCZ. However, their association with cognitive dysfunction in first-episode SCZ patients has not been thoroughly investigated.

AIM

To explore the interaction effects between cognitive function and inflammatory cytokines and BDNF in first-episode SCZ.

METHODS

The current study is a cross-sectional case-control investigation that recruited 84 patients with first-episode SCZ (SCZ group) and 80 healthy controls (HCs group) at the Huzhou Third Municipal Hospital between August 2021 and September 2023. ELISA was employed to measure the serum levels of interleukin (IL)-1β, IL-4, IL-6, IL-10, and BDNF. The Chinese brief cognitive test (C-BCT) and the positive and negative syndrome scales were measured the severity of cognitive impairment and psychiatric symptoms.

RESULTS

Compared to the HC group, the SCZ group exhibited elevated IL-1β and IL-6 levels, decreased BDNF levels, and reduced C-BCT scores (all P < 0.001). In SCZ, BDNF was negatively correlated with IL-6 (r = -0.324, P < 0.05). Information processing speed was negatively correlated with IL-6 (r = -0.315, P < 0.05) and positively with BDNF (r = 0.290, P < 0.05); attention, working memory, comprehensive ability, and executive function were negatively correlated with IL-1β and IL-6 (all P < 0.05) and positively with BDNF (all P < 0.05). Multiple regression analysis showed IL-6 influenced C-BCT dimensions (β = -0.218 to -0.327, all P < 0.05); attention and executive ability were influenced by IL-1β (β = -0.199 to -0.261, all P < 0.05); comprehensive executive ability was influenced by BDNF (β = 0.209, P < 0.05).

CONCLUSION

Our findings suggested that interrelationships between immune dysfunction and neurotrophic deficiency might underlie the pathological mechanisms of cognitive impairments in first-episode SCZ patients.

Abnormal hedonic process in patients with stable schizophrenia: Relationships to negative symptoms and social functioning

Background

Anhedonia is a deficit of dynamic reward process, and a large proportion of schizophrenia patients continue to experience anhedonia even during the stable phase. However, few studies have examined the multiple aspects of performance in reward processing in patients with stable schizophrenia and evidence suggests that physical and cognitive effort may involve different neural mechanisms.

Methods

Parallel measures of effort-based expenditure for reward tasks (EEfRT) and self-report questionnaires of pleasure were applied in 61 patients with stable schizophrenia (SSZ) and 46 healthy controls (HCs), and percentages of hard task choices (HTC%) were used to assess motivation in reward processing. Negative symptoms, neurocognitive and social function were evaluated in SSZ patients, and associations with performance in reward tasks were explored.

Results

SSZ patients reported more severe consummatory and anticipatory anhedonia and social anhedonia. HTC% in reward tasks of SSZ patients were significantly lower than that of HCs, especially in cognitive-effort tasks. HTC% in cognitive tasks were correlated with motivation and pleasure dimension of negative symptoms, whereas HTC% in physical tasks were associated with expression dimension. Anticipatory anhedonia and negative symptoms were correlated with Personal and Social Performance Scale (PSP) scores.

Conclusion

Patients with stable schizophrenia have social anhedonia, physically consummatory and anticipatory anhedonia and reduced reward motivation. They are less willing to make cognitive effort than physical effort for reward. The different associations of physical and cognitive effort with negative symptoms indicate physical and cognitive effort may represent disparate neuropsychological processes. Anticipatory anhedonia is closely related to social functioning.

Eye movements as predictor of cognitive improvement after cognitive remediation therapy in patients with schizophrenia

Aim

Baseline cognitive functions of patients predicted the efficacy of cognitive remediation therapy (CRT), but results are mixed. Eye movement is a more objective and advanced assessment of cognitive functions than neuropsychological testing. We aimed to investigate the applicability of eye movements in predicting cognitive improvement after patients with schizophrenia were treated with CRT.

Methods

We recruited 79 patients with schizophrenia to complete 8 weeks of CRT and assessed their cognitive improvement outcomes. Eye movements were assessed by prosaccades, antisaccades, and free-viewing tasks at baseline, and neuropsychological tests in four cognitive domains were assessed before and after treatment to calculate treatment outcomes. Predictors of demographic information, clinical characteristics, and eye movement measures at baseline on cognitive improvement outcomes were analyzed using logistic regression analysis. We further compared the predictive performance between eye movement measurements and neuropsychological test regarding the effect of CRT on cognitive improvement, and explored factors that could be affect the treatment outcomes in different cognitive domains.

Results

As operationally defined, 33 patients showed improved in cognition (improved group) and 46 patients did not (non-improved group) after CRT. Patients with schizophrenia being employed, lower directional error rate in antisaccade task, and lower the gap effect (i.e., the difference in saccadic latency between the gap condition and overlap condition) in prosaccade task at baseline predicted cognitive improvement in CRT. However, performance in the free-viewing task not associated with cognitive improvement in patients in CRT. Our results show that eye-movement prediction model predicted the effect of CRT on cognitive improvement in patients with schizophrenia better than neuropsychological prediction model in CRT. In addition, baseline eye-movements, cognitive reserve, antipsychotic medication dose, anticholinergic cognitive burden change, and number of training sessions were associated with improvements in four cognitive domains.

Conclusion

Eye movements as a non-invasiveness, objective, and sensitive method of evaluating cognitive function, and combined saccadic measurements in pro- and anti-saccades tasks could be more beneficial than free-viewing task in predicting the effect of CRT on cognitive improvement in patients with schizophrenia.

Decline in Working Memory in Stable Schizophrenia May Be Related to Attentional Impairment: Mediating Effects of Negative Symptoms, a Cross-Sectional Study

Background

Schizophrenia (SCZ) is a severe mental illness, Cognitive deficits and negative symptoms (NS) are prevalent in individuals with SCZ and are crucial indicators of functional recovery. It is well known that cognitive symptoms and negative symptoms are interrelated and that negative symptoms can affect the ability to take cognitive tests. However, the specific relationship between attention, working memory (WM), and NS in stable SCZ remains unclear. This study aims to explore these associations and provide valuable insights for the subsequent treatment of SCZ.

Methods

We conducted a comprehensive assessment of 145 patients with stable SCZ using the Chinese Brief Neurocognitive Suite of Tests (C-BCT) and the Positive and Negative Symptom Scale (PANSS).

Results

Patients with abnormal cognition exhibited significantly higher PANSS total scores, cognitive symptom scores, and NS than those with normal cognition (P<0.05). Pearson's correlation analysis revealed significant positive correlations between digital breadth(DB) and continuous operation(CO) (r=0.389, P<0.001), as well as a significant negative correlation between DB and NS (r=-0.291, P<0.001). Moreover, CO showed a negative correlation with NS (r=-0.173, P<0.05). However, no significant correlations were found between the digital breadth-anterograde score and CO or NS (r=0.148, P>0.05; r=-0.068, P>0.05). Notably, NS were identified as a mediator in the relationship between attention and WM (effect size=0.024).

Conclusion

Our findings highlight significant associations between WM, attention, and NS in individuals with stable SCZ. Moreover, attention not only directly impacts WM but also indirectly influences it through NS. Addressing cognitive deficits and NS in the treatment of SCZ may lead to improved overall outcomes for affected individuals.

Transcranial ultrasound stimulation modulates the interhemispheric balance of excitability in human motor cortex

Background. Low-intensity transcranial ultrasound stimulation (TUS) could induce both immediate and long-lasting neuromodulatory effects in human brains. Interhemispheric imbalance at prefrontal or motor cortices generally associates with various cognitive decline in aging and mental disorders. However, whether TUS could modulate the interhemispheric balance of excitability in human brain remains unknown.Objective. This study aims to explore whether repetitive TUS (rTUS) intervention can modulate the interhemispheric balance of excitability between bilateral motor cortex (M1) in healthy subjects.Approach. Motor evoked potentials (MEPs) at bilateral M1 were measured at 15 min and 0 min before a 15 min active or sham rTUS intervention on left M1 and at 0 min, 15 min and 30 min after the intervention, and the Chinese version of brief neurocognitive test battery (C-BCT) was conducted before and after the intervention respectively. Cortical excitability was quantified by MEPs, and the long-lasting changes of MEP amplitude was used as an index of plasticity.Results. In the active rTUS group (n= 20), the ipsilateral MEP amplitude increased significantly compared with baselines and lasted for up to 30 min after intervention, while the contralateral MEP amplitude decreased lasting for 15 min, yielding increased laterality between bilateral MEPs. Furthermore, rTUS intervention induced changes in some C-BCT scores, and the changes of scores correlated with the changes of MEP amplitudes induced by rTUS intervention. The sham rTUS group (n= 20) showed no significant changes in MEPs and C-BCT scores. In addition, no participants reported any adverse effects during and after the rTUS intervention, and no obvious temperature increase appeared in skull or brain tissues in simulation.Significance. rTUS intervention modulated the plasticity of ipsilateral M1 and the interhemispheric balance of M1 excitability in human brain, and improved cognitive performance, suggesting a considerable potential of rTUS in clinical interventions.

A prospective cohort study of depression (PROUD) in China: rationale and design

Background

Major depressive disorder (MDD) imposes a heavy global disease burden. However, current etiology, diagnosis and treatment remain unsatisfactory and no previous study has resolved this problem. Building on the strengths and limitations of previous cohort studies of MDD, the prospective cohort study of depression (PROUD) is a 3-year large-scale cohort study designed to collect multidimensional data with a flexible follow-up schedule and strategy. The goal is to establish a nationally representative, high-quality, standardized depression cohort to support precise diagnosis and treatment of MDD and address the gap in current research.

Methods

PROUD is a patient-based, nationally representative multicenter prospective cohort study with baseline and 3-year follow-up assessments. It will be carried out from January 2022 to December 2026 in 52 qualified tertiary hospitals in China. A total of 14,000 patients diagnosed with MDD, according to the DSM-5 criteria, and aged ≥ 16 years, will be recruited to PROUD. Participants aged 18-65 years who have not received any treatment during a depressive episode will be included in the precision medicine cohort (PMC) of PROUD (n=4,000). Patients who meet the general eligibility criteria but not the PMC criteria will be included in the naturalistic observation cohort (NOC) of PROUD (n=10,000). A multiple follow-up strategy, including scheduled, remote, telephone, external visits and patient self-reports, will be implemented to collect comprehensive sociodemographic, clinical information, biospecimens, neuroimaging, cognitive function and electrophysiology data and digital phenotypes according to strict standard operating procedures implemented across centers. Trial registration: ChiCTR2200059053, registered on 23 April 2022, http://www.chictr.org.cn/showproj.aspx?proj=165790.

Conclusions

PROUD is a prospective cohort study of MDD patients in China. It will provide a comprehensive database facilitating further analyses and aiding the development of homeostatic and precision medicine in China.