Alkan Erkan, Davies Geoff, Evans Simon L
Faculty of Health and Medical Sciences, University of Surrey, Guildford, Surrey, UK.
Brighton & Sussex Medical School/Sussex Partnership NHS Foundation Trust, Sussex, UK.
NPJ Schizophr. 2021 Mar 18;7(1):20. doi: 10.1038/s41537-021-00149-0.
Cognitive impairments are a core and persistent characteristic of schizophrenia with implications for daily functioning. These show only limited response to antipsychotic treatment and their neural basis is not well characterised. Previous studies point to relationships between cortical thickness and cognitive performance in fronto-temporal brain regions in schizophrenia patients (SZH). There is also evidence that these relationships might be independent of symptom severity, suggesting dissociable disease processes. We set out to explore these possibilities in a sample of 70 SZH and 72 age and gender-matched healthy controls (provided by the Center of Biomedical Research Excellence (COBRE)). Cortical thickness within fronto-temporal regions implicated by previous work was considered in relation to performance across various cognitive domains (from the MATRICS Cognitive Battery). Compared to controls, SZH had thinner cortices across most fronto-temporal regions and significantly lower performance on all cognitive domains. Robust relationships with cortical thickness were found: visual learning and attention performance correlated with bilateral superior and middle frontal thickness in SZH only. Correlations between attention performance and right transverse temporal thickness were also specific to SZH. Findings point to the importance of these regions for cognitive performance in SZH, possibly reflecting compensatory processes and/or aberrant connectivity. No links to symptom severity were observed in these regions, suggesting these relationships are dissociable from underlying psychotic symptomology. Findings enhance understanding of the brain structural underpinnings and possible aetiology of cognitive impairment in SZH.
认知障碍是精神分裂症的核心且持续存在的特征，对日常功能有影响。这些障碍对抗精神病药物治疗的反应有限，其神经基础也未得到很好的表征。先前的研究指出精神分裂症患者（SZH）额颞脑区的皮质厚度与认知表现之间存在关联。也有证据表明这些关联可能独立于症状严重程度，提示存在可分离的疾病过程。我们着手在70名SZH患者和72名年龄及性别匹配的健康对照者（由卓越生物医学研究中心（COBRE）提供）的样本中探索这些可能性。考虑到先前研究涉及的额颞区域内的皮质厚度与跨各种认知领域（来自MATRICS认知电池）的表现之间的关系。与对照组相比，SZH患者在大多数额颞区域的皮质更薄，并且在所有认知领域的表现明显更低。发现了与皮质厚度的稳健关系：视觉学习和注意力表现仅与SZH患者双侧额上回和额中回厚度相关。注意力表现与右侧颞横回厚度之间的相关性也仅在SZH患者中存在。研究结果指出这些区域对SZH患者认知表现的重要性，可能反映了代偿过程和/或异常连接。在这些区域未观察到与症状严重程度的关联，表明这些关系与潜在的精神病症状学可分离。研究结果增进了对SZH患者认知障碍的脑结构基础及可能病因的理解。
