Schizophrenia Research-Cognition最新文献

Background

Schizophrenia is associated with impairments in verbal episodic memory. Strategy for Semantic Association Memory (SESAME) training represents a promising cognitive remediation program to improve verbal episodic memory. Virtual reality (VR) may be a novel tool to increase the ecological validity and transfer of learned skills of traditional cognitive remediation programs. The present proof-of-concept study aimed to assess the feasibility, acceptability, and preliminary efficacy of a VR-based cognitive remediation module inspired by SESAME principles to improve the use of verbal episodic memory strategies in schizophrenia.

Methods

Thirty individuals with schizophrenia/schizoaffective disorder completed this study. Participants were randomized to either a VR-based verbal episodic memory training condition inspired by SESAME principles (intervention group) or an active control condition (control group). In the training condition, a coach taught semantic encoding strategies (active rehearsal and semantic clustering) to help participants remember restaurant orders in VR. In the active control condition, participants completed visuospatial puzzles in VR. Attrition rate, participant experience ratings, and cybersickness questionnaires were used to assess feasibility and acceptability. Trial 1 of the Hopkins Verbal Learning Test – Revised was administered pre- and post-intervention to assess preliminary efficacy.

Results

Feasibility was demonstrated by a low attrition rate (5.88 %), and acceptability was demonstrated by limited cybersickness and high levels of enjoyment. Although the increase in the number of semantic clusters used following the module did not reach conventional levels of statistical significance in the intervention group, it demonstrated a notable trend with a medium effect size (t = 1.48, p = 0.15, d = 0.54), in contrast to the control group where it remained stable (t = 0.36, p = 0.72, d = 0.13). These findings were similar for the semantic clustering ratio in the intervention (t = 1.61, p = 0.12, d = 0.59) and control (t = 0.36, p = 0.72, d = 0.13) groups. There was no significant change in the number of recalled words in either group following VR immersion.

Discussion

This VR intervention was feasible, acceptable, and may be useful for improving the use of semantic encoding strategies. These findings support the use of more ecological approaches for the treatment of cognitive impairments in schizophrenia, such as VR-based cognitive remediation.

Deficits in executive control of attention have been reported in schizophrenia patients, but can be ameliorated by treatment of atypical antipsychotics along with the symptoms. However, it remains unclear whether this effect is related to a modulation of hemispheric asymmetry in executive control by the medicine. In this behavioral study, we employed a lateralized version of the attention network test to examine the hemispheric asymmetry of executive control in schizophrenia patients before and after olanzapine treatment, compared to matched healthy controls. Executive control was measured as a conflict effect, indexed as the response time (RT) difference between incongruent versus congruent flanker conditions, and was compared between stimuli presented in the left and the right visual field (i.e., processed by right versus left hemisphere of the brain). Results showed that pre-treatment schizophrenia patients revealed a right hemisphere superiority in conflict effect (i.e., a smaller effect in the right hemisphere than in the left hemisphere), driven by the incongruent condition. Olanzapine treatment reduced this right hemisphere superiority by improving the efficiency of the left hemisphere in the incongruent condition. These results suggested that olanzapine treatment may improve the efficiency of executive control in the left hemisphere in schizophrenia patients.

The hematopoietically-expressed homeobox gene (HHEX) played a critical role in regulating the immune system that the abnormality of which was involved in the psychopathology and cognitive deficits of psychiatric disorders. The aim of this study was to investigate the effect of HHEX rs1111875 polymorphism on the susceptibility and cognitive deficits of first-episode schizophrenic patients (FSP). We assessed cognitive function in 239 first-episode patients meeting DSM-IV for schizophrenia, and 368 healthy controls using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). The HHEX rs1111875 polymorphism was genotyped. Our results showed that the allelic and genotypic frequencies of HHEX rs1111875 polymorphism didn't differ between FSP and healthy controls (both p > 0.05) after adjusting for sex and age. Cognitive test scores in FSP were significantly lower than those in healthy controls on all scales (all p < 0.001) except for the visuospatial/constructional score (p > 0.05) after adjusting for covariates. There was a significant genotype (p < 0.05) rather than genotype × diagnosis (p > 0.05) effect on the delayed memory score after adjusting for covariates. The HHEX rs1111875 polymorphism was significantly associated with the delayed memory score in FSP (p < 0.05), but not in healthy controls (p > 0.05) after adjusting for covariates. Our findings supported that the HHEX rs1111875 polymorphism did not contribute to the susceptibility to FSP. However, this polymorphism might influence the delayed memory in FSP. Moreover, FSP had poorer cognitive function than healthy controls except for the visuospatial/constructional domain.

Face and emotion recognition are crucial components of social cognition. We aimed to compare them in patients diagnosed with schizophrenia (SCZ), ultra-high risk for psychosis (UHR), unaffected siblings of schizophrenia patients (SIB), and healthy controls (HC). Methods: One hundred sixty-six participants (45 SCZ, 14 UHR, 45 SIB, and 62 HC) were interviewed with the Structured Clinical Interview for DSM-5 (SCID-5). Positive and Negative syndrome scale (PANSS), PennCNB Facial Memory (CPF), and Emotion Recognition Task (ER40) were applied. Results: In CPF, SCZ performed significantly lower than SIB and HC. SIB was also significantly lower than HC for total correct responses. The sample size of the UHR group was small, and the statistical comparisons did not reach a significance, however, a trend towards decreased performance between the SCZ and SIB was found. In ER40, SCZ performed significantly lower than HC and SIB in all domains, except for the insignificant findings for angry ER between SIB and SCZ. SIB also performed significantly lower than HC for angry, negative, and total ER. UHR was similar to SCZ for happy and sad ER and performed significantly lower than HC for happy ER. The effect of SCZ diagnosis on the efficiency of CPF and ER40 was significant when corrected for age and education. For SCZ, PANSS also significantly affected the CPF and ER40. Conclusion: Our findings suggest varying levels of face and emotion recognition deficits in individuals with SCZ, UHR, and SIB. Face and emotion recognition deficits are promising schizophrenia endophenotypes related to social cognition.

Background

Cognitive alterations have been reported in early stages of psychosis including people with First Episode Psychosis (FEP), Clinical High-Risk Mental State (CHR), and Psychotic-Like Experience (PLE). This study aimed to compare the cognitive function in early stages of psychosis using the Montreal Cognitive Assessment (MoCA), a low-cost and brief assessment tool of cognitive functions.

Methods

A total of 154 individuals, including 35 with FEP, 38 CHR, 44 PLE, and 37 healthy controls (HC), were evaluated with the MoCA in Santiago, Chile. We calculated the mean total score of the MoCA and the standard deviation of the mean. Groups were assessed for a trend to lower scores in a pre-determined sequence (HC > PLE > CHR > FEP) using the Jonckheere-Terpstra test (T_JT).

Results

The mean total MoCA scores were 24.8 ± 3.3 in FEP, 26.4 ± 2.4 in CHR, 26.4 ± 2.3 in PLE, and 27.2 ± 1.8 in HC. The analyses revealed a significant trend (p < 0.05) toward lower MoCA individual domain scores and MoCA total scores in the following order: HC > PLE > CHR > FEP. The mean total scores of all groups were above the cut-off for cognitive impairment (22 points).

Conclusions

The MoCA describes lower scores in cognition across early stages of psychosis and may be a useful low-cost assessment instrument in early intervention centers of poorly resourced settings.

Background

Although both anemia and schizophrenia (SCZ) can cause cognitive decline, it is unclear whether anemia worsens cognitive decline in patients with SCZ. The primary objective of this study was to investigate the prevalence of anemia and the relationship between anemia, SCZ symptom severity, and cognitive function in patients with SCZ.

Methods

We obtained demographic and clinical data from 1690 inpatients with SCZ. All psychiatric symptoms and cognitive functioning were assessed by the Positive and Negative Syndrome Scale (PANSS), the Mini-Mental State Examination (MMSE), and the Repeated Battery for the Assessment of Neuropsychological Status (RBANS). Hemoglobin (HGB) values as well as red blood cell (RBC) counts were collected by routine blood tests.

Results

The proportion of anemia in patients with SCZ was 26.36 % (383/1453). Compared to SCZ patients without anemia, SCZ patients with anemia were older, had a lower bodyweight, a smaller waist circumference and lower apolipoprotein B levels, but longer QT intervals. Further logistic regression analysis revealed that anemia was associated with age, gender, and weight. In addition, there was no difference in cognitive function between SCZ patients with and without anemia.

Conclusion

Our findings suggest a high proportion of anemia in patients with chronic SCZ in the Han Chinese population. Several demographic and clinical variables are associated with anemia in SCZ patients.

Introduction

Cannabis use impairs cognitive performance in healthy subjects; several studies have shown improved cognitive outcomes in schizophrenic patients using cannabis. The aim of this study was to evaluate the effects of cannabis use on cognitive function in Moroccan patients with schizophrenia who were cannabis users.

Method

Two groups were recruited in a Moroccan University Psychiatric Centre. Fifty patients diagnosed with schizophrenia according to the DSM-V who were cannabis users (SZ CANN +) and forty-nine patients diagnosed with schizophrenia according to DSM-V who do not use cannabis (SZ CANN-). Cognitive functioning was assessed using the CogState neuropsychological battery.

Results

The results of the study suggest that SZ CANN- patients performed better in the test of psychomotor function, attention and verbal memory. While SZ CANN+ patients performed better in the test of working memory, visual memory and emotional recognition. We found no relationship between SZ CANN+ patients and SZ CANN- patients concerning executive function.

Conclusions

Our results suggest that cannabis use may have different effects on neurocognitive functioning. It is associated with disorders of psychomotor function, attention and verbal memory. So, it is associated with an improvement in working memory, visual memory and emotion recognition.

This study investigated the relationships between negative and positive automatic thoughts and clinical variables in patients with schizophrenia. The participants included 36 patients with schizophrenia (male = 16; female = 20; age = 42.86 ± 9.40) who were outpatients in the Department of Psychiatry at Tokushima University Hospital. We used the Automatic Thoughts Questionnaire-Revised (ATQ-R), Positive and Negative Syndrome Scale (PANSS), Calgary Depression Scale for Schizophrenia (CDSS), and Brief Assessment of Cognition in Schizophrenia (BACS) to assess negative and positive automatic thoughts, positive and negative symptoms, depressive symptoms, and neurocognition, respectively. Spearman rank correlation coefficients were calculated to determine the relationships between negative and positive automatic thoughts and clinical variables. No relationship was observed between negative and positive automatic thoughts. Negative automatic thoughts were related to depressive symptoms. Positive automatic thoughts were related to neurocognition. We therefore surmise that each automatic thought might have different clinical features and outcomes, and should therefore be treated accordingly.

Range adaptation refers to the representation of a stimulus value based on its relative position in the range of pre-experienced values. Altered range adaptation in value representation may be related to motivation and pleasure (MAP) deficit in schizophrenia (SCZ). This follow-up study examined the relationship between range adaptation performance and MAP symptoms in SCZ patients. We recruited 26 schizophrenia patients and followed them for 1 year. They completed an experimental task for estimating their range adaptation to outcome value (OV) and expected value (EV) at baseline and after 1 year. At baseline, we found a marginally significant and negative correlation between OV adaptation and avolition symptoms in SCZ patients. Moreover, the 1-year change of EV adaptation was significantly and negatively correlated with the change of self-report pleasure experience. Our results suggest that range adaptation may track the variations of MAP symptoms in SCZ.