Schizophrenia Bulletin最新文献

Background and hypothesis: The cognitive model of negative symptoms posits that defeatist performance beliefs (DPB) contribute to negative symptoms in schizophrenia, such as anhedonia. The associations between specific DPB dimensions (overvaluing success, overvaluing failure, and overvaluing social evaluation) and daily-life pleasure have not been well-studied. Using experience sampling methodology (ESM), we examined associations between multidimensional DPB and momentary consummatory and anticipatory pleasure across daily contexts in early psychosis (EP) patients and healthy controls (HC).

Study design: Thirty-three EP and 35 HC completed ESM assessment of momentary consummatory and anticipatory pleasure, as well as current and anticipated activity type (functional vs leisure) and social company (with others vs alone), 10 times daily for 6 days. Multidimensional DPB was assessed at baseline. The associations between DPB dimensions and momentary pleasure in EP and HC, as well as the effects of activity type and social company on the associations, were examined with multilevel modeling.

Study results: A total of 2609 ESM responses were analyzed. Across EP and HC, overvaluing success and failure DPB were negatively associated with momentary consummatory and anticipatory pleasure. EP exhibited a more negative association between overvaluing failure DPB and momentary consummatory pleasure when engaging in functional (vs leisure) activities. The same pattern of result emerged for momentary anticipatory pleasure when anticipating to engage in functional (vs leisure) activities.

Conclusions: With a modest sample, specific DPB dimensions showed distinct associations with pleasure in daily-life contexts. Targeting overvaluing failure DPB in patients may help alleviate anhedonia during functional activities, potentially improving patients' functioning.

Background: Brain volume alterations in those at clinical high risk (CHR) of psychosis have been reported in many studies. However, the association between these alterations and the longitudinal trajectory of changes in symptoms and functioning remains unexplored.

Study design: T1-weighted magnetic resonance imaging (MRI) scans were acquired from 226 CHR and 65 healthy controls (HC) recruited from the EU-GEI high-risk study. Five a priori regions of interest were examined and segmented using FreeSurfer: total gray matter (GM) volume, anterior cingulate cortex (ACC), hippocampus, fusiform gyri, and insula. Brain volumes in the CHR and HC groups were compared at baseline. In the CHR group, linear mixed models were used to investigate the association between baseline brain volume and longitudinal changes in positive symptoms, negative symptoms, and functioning over a 2-year follow-up period. We also compared CHR participants who later transitioned to psychosis (CHR-T, n = 48) and those who did not (CHR-NT, n = 178) in terms of their trajectory of symptoms and functioning.

Study results: Compared with HC, CHR participants had lower total GM and fusiform volume at baseline. Lower total GM and hippocampus volume at baseline were associated with higher levels of positive symptoms at baseline and follow-up in CHR individuals, and lower baseline hippocampus volume also predicted future transition. CHR-T and CHR-NT individuals demonstrated distinct symptoms and functioning trajectories over time.

Conclusion: Our findings suggest that CHR individuals show baseline differences in brain structure compared to HC, which may also predict changes in positive symptoms over the subsequent 2 years.

Background: The cognitive model conceptualizes negative symptoms within a theoretical framework highlighting dysfunctional beliefs as maintenance factors. Although several beliefs have been proposed as potential mechanistic targets for psychosocial interventions, no study has comprehensively examined their relationships with negative symptoms and functional outcomes. This study aimed to evaluate the pathways from each of the 6 primary dysfunctional beliefs posited by the cognitive model to negative symptoms and functioning.

Study design: The sample consisted of 132 participants with schizophrenia spectrum disorders. The direct and indirect pathways from dysfunctional beliefs to negative symptoms and functioning, respectively, were examined using 2 approaches. A principal components analysis of the 6 beliefs produced a single factor used for path modeling. Separate models were then estimated for each belief to evaluate their unique contributions. Model specificity was assessed by comparing effects for overall negative symptoms versus the diminished motivation subdomain.

Study results: Both approaches revealed a consistent pattern, with dysfunctional beliefs showing significant direct effects on negative symptoms and indirect effects on functioning via negative symptoms. Significant individual paths were observed for defeatist performance beliefs, asocial beliefs, low expectancies for success, low expectancies for pleasure, and perceptions of limited resources, but not for internalized stigma. Models focused on diminished motivation demonstrated superior fit.

Conclusions: Findings support the cognitive model as a viable framework for informing cognitive-behavioral interventions for negative symptoms. By identifying consistent relationships with motivation and functioning, the results highlight the potential clinical utility of targeting specific dysfunctional beliefs to alleviate negative symptoms and enhance treatment outcomes.

Background and hypothesis: Cognitive deficits are central to schizophrenia-spectrum disorders and already present in many patients at first-episode psychosis (FEP). Prior meta-analyses suggest cognitive deficits remain relatively stable, but most of them tracked patients for only a few years and rarely compared trajectories directly with matched healthy controls (HCs). We aimed to characterize cognitive trajectories over long-term follow-ups.

Study design: Following PRISMA-2020 guidelines, we searched databases for longitudinal studies of cognition in recent-onset psychosis. Forty-nine datasets (3693 FEP and 1399 HCs) were included, with follow-ups ranging from 2 to 25 years. Random-effects meta-analyses quantified within-group change (FEP and HC separately) and between-group differences (FEP-vs.-HC) across short (2-5 years), mid (5-10 years), and long-term (≥10 years) intervals. Meta-regressions examined the influence of clinical moderators.

Study results: Both FEP patients and HCs showed either stable performance or small effect-size improvements in global (FEP: d = 0.22, P < .0001) and domain-specific cognition over long-term, with no evidence of progressive deterioration. Direct comparisons revealed no FEP-vs.-HC differences in global cognitive change overall (d = 0.05, P = .568) or within any follow-up interval (short, mid, and long). Across domains, the only exception was attention, where patients improved compared to controls. Changes in positive and negative symptoms were unrelated to changes in global cognition.

Conclusions: Neuropsychological performance in FEP remains stable for at least a decade, with modest gains largely attributable to practice effects and no sign of neurodegenerative decline. These trait-like deficits appear partly independent of long-term symptom changes, and further support neurodevelopmental over neurodegenerative models of schizophrenia.

Background and hypothesis: Auditory verbal hallucinations (AVH) are hypothesized to result from failures in corollary discharge mechanisms to correctly predict self-initiated inner speech. However, the role of motor preparation in inner speech, during which sensorimotor predictions are formed, remains unclear. This study aimed to test the hypothesis by examining the relationship between AVH and an electrophysiological marker of action preparation: the contingent negative variation (CNV).

Study design: Participants completed an electroencephalographic paradigm. In the Active condition, they imagined an inner syllable at a cued moment coinciding with the presentation of an audible syllable. In the Passive condition, participants passively listened to audible syllables. The amplitude of the late CNV preceding inner speech production was compared with that associated with passive listening across 3 groups: (1) schizophrenia spectrum patients with current AVH (SZAVH+, n = 58), (2) schizophrenia spectrum patients without current AVH (SZAVH-, n = 50), and (3) healthy controls (HC, n = 49).

Study results: The HC group showed a more negative late CNV in the Active condition compared with the Passive condition. In contrast, the SZAVH+ and SZAVH- groups showed positive-going slow cortical potentials in both conditions, with less positivity in the Active condition in the former. This pattern significantly predicted AVH status.

Conclusions: These findings provide evidence of motor preparation dysfunction during inner speech in schizophrenia spectrum disorders. The distinct pattern of deficits observed in hallucinators may reflect imprecise corollary discharges theorized to underlie some AVH. Premovement neural indices may provide a novel window into abnormalities in prediction formation.