King's College London, Department of Psychosis Studies (Box P063), Institute of Psychiatry, King's Health Partners, De Crespigny Park, London, UK. jennifer.1.o'
Schizophr Res. 2012 May;137(1-3):104-9. doi: 10.1016/j.schres.2012.01.041. Epub 2012 Feb 16.
Estimates of pre-morbid IQ are widely used to measure the trajectory of cognitive function and decline in people with schizophrenia. This study examined the usefulness of two indices of decline to identify cognitive subtypes in first episode psychosis, and to determine the specificity of non-IQ neuropsychological impairments in this population. Neuropsychological data were collected from 118 first episode psychosis patients and compared to 118 epidemiologically matched controls. The National Adult Reading Test (NART) and the Information subtest of the WAIS-III were compared as indicators of crystallised intelligence or 'pre-morbid IQ'. Measurement of NART minus current full scale IQ (FSIQ) (where 10 points discrepancy is the decline criterion) did not reveal a large group of individuals with 'deteriorating' IQ patterns. Using the Information subtest and the same decline criteria, a 'deteriorating' patient group emerged (36%) but was matched by a larger 'deteriorating' control group (45%). The 'deteriorating' patient group performed at a low IQ level for tasks that loaded highly on performance ability but a relatively high level for tasks measuring verbal skills. Verbal memory discriminated patients from controls better than IQ. Compared to controls, patients showed large selective impairments of verbal episodic memory (effect size, d=1.4) These data suggest that in first episode populations, caution should be exercised in inferring deterioration of IQ from discrepancies between reading-based and other IQ tests. Rather, sub-groups of patients and controls do show greater verbal aptitude in comparison to performance skills. Memory is generally impaired in first episode patients regardless of IQ.
对发病前智商的估计广泛用于衡量精神分裂症患者认知功能和认知能力下降的轨迹。本研究检验了两种下降指数在识别首发精神病认知亚型方面的有效性，并确定了这一人群中非智商神经心理损伤的特异性。从 118 名首发精神病患者中收集了神经心理学数据，并与 118 名在流行病学上相匹配的对照组进行了比较。国家成人阅读测试（NART）和韦氏成人智力量表第三版的信息子测验被用来作为衡量晶体智力或“发病前智商”的指标。NART 减去当前全量表智商（FSIQ）的测量（其中 10 分差异是下降标准）并没有显示出大量 IQ 模式“恶化”的个体。使用信息子测验和相同的下降标准，出现了一个“恶化”的患者组（36%），但与之匹配的是更大的“恶化”对照组（45%）。“恶化”的患者组在高度依赖于表现能力的任务中表现出较低的智商水平，但在衡量语言技能的任务中表现出相对较高的智商水平。言语记忆比智商更能区分患者和对照组。与对照组相比，患者表现出较大的言语情景记忆选择性损伤（效应大小，d=1.4）。这些数据表明，在首发人群中，从基于阅读的测试和其他智商测试之间的差异推断智商下降时应谨慎。相反，患者和对照组的亚组确实表现出与表现技能相比更大的语言能力。无论智商如何，记忆通常在首发患者中受损。
