Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, 446 E Ontario St, Suite 7-100, Chicago, IL 60611, USA.
Schizophr Res. 2011 Dec;133(1-3):68-76. doi: 10.1016/j.schres.2011.08.017. Epub 2011 Oct 7.
Schizophrenia is a severe psychiatric illness with widespread impairments of cognitive functioning; however, a certain percentage of subjects are known to perform in the normal range on neuropsychological measures. While the cognitive profiles of these individuals have been examined, there has been relatively little attention to the neuroanatomical characteristics of this important subgroup. The aims of this study were to statistically identify schizophrenia subjects with relatively normal cognition, examine their neuroanatomical characteristics relative to their more impaired counterparts using cortical thickness mapping, and to investigate relationships between these characteristics and demographic variables to better understand the nature of cognitive heterogeneity in schizophrenia. Clinical, neuropsychological, and MRI data were collected from schizophrenia (n = 79) and healthy subjects (n = 65). A series of clustering algorithms on neuropsychological scores was examined, and a 2-cluster solution that separated subjects into neuropsychologically near-normal (NPNN) and neuropsychologically impaired (NPI) groups was determined most appropriate. Surface-based cortical thickness mapping was utilized to examine differences in thinning among schizophrenia subtypes compared with the healthy participants. A widespread cortical thinning pattern characteristic of schizophrenia emerged in the NPI group, while NPNN subjects demonstrated very limited thinning relative to healthy comparison subjects. Analysis of illness duration indicated minimal effects on subtype classification and cortical thickness results. Findings suggest a strong link between cognitive impairment and cortical thinning in schizophrenia, where subjects with near-normal cognitive abilities also demonstrate near-normal cortical thickness patterns. While generally supportive of distinct etiological processes for cognitive subtypes, results provide direction for further examination of additional neuroanatomical differences.
精神分裂症是一种严重的精神疾病，广泛存在认知功能障碍；然而，已知有一定比例的患者在神经心理学测试中表现正常。虽然这些个体的认知特征已经被研究过，但对于这个重要亚组的神经解剖学特征关注相对较少。本研究的目的是通过统计方法识别认知功能相对正常的精神分裂症患者，使用皮质厚度映射技术检查他们与认知功能受损患者相比的神经解剖学特征，并研究这些特征与人口统计学变量之间的关系，以更好地理解精神分裂症认知异质性的本质。从精神分裂症患者（n = 79）和健康受试者（n = 65）中收集了临床、神经心理学和 MRI 数据。检查了一系列神经心理学评分的聚类算法，并确定了最适合的 2 聚类解决方案，将患者分为神经心理学上接近正常（NPNN）和神经心理学受损（NPI）组。利用基于表面的皮质厚度映射来检查与健康参与者相比，精神分裂症亚型的变薄差异。NPI 组出现了精神分裂症的广泛皮质变薄模式，而 NPNN 患者与健康对照组相比，皮质变薄非常有限。对疾病持续时间的分析表明，对亚型分类和皮质厚度结果的影响最小。研究结果表明，精神分裂症中认知障碍与皮质变薄之间存在很强的联系，认知能力接近正常的患者也表现出接近正常的皮质厚度模式。虽然这些结果普遍支持认知亚类的不同病因过程，但为进一步检查其他神经解剖学差异提供了方向。
