General and social cognition in first episode schizophrenia: identification of separable factors and prediction of functional outcome using the IntegNeuro test battery

OBJECTIVE: It is increasingly recognized that cognitive assessments, unlike symptom ratings, provide a reliable predictor of functional outcome in schizophrenia. This study evaluated the utility of the 'IntegNeuro' computerized test battery for assessing cognition in first episode schizophrenia. We determined the presence of separable factors of general and social cognition, their equivalence to the consensus domains identified by the NIMH MATRICS project, and their effectiveness in predicting real world functional outcomes. METHOD: Fifty six first episode schizophrenia (FES) patients and 112 matched healthy controls were assessed on the touchscreen-based 'IntegNeuro' cognitive test battery and FES patients for social functioning (SOFAS) and quality of life (WHOQOL-BREF). RESULTS: Principal components analysis identified i) six factors corresponding to MATRICS domains of general cognition ('Information Processing Speed', 'Verbal Recall', 'Working Memory Capacity', 'Sustained Attention/Vigilance', 'Verbal Processing', 'Executive Function'), ii) an 'Emotional Intelligence' factor corresponding to the MATRICS social cognition domain, and iii) an additional 'Sensori-Motor Function' factor of general cognition and 'Negativity' factor of social cognition. Patients showed impairments relative to controls across all factors, but especially for Working Memory Capacity, followed by Verbal Memory, Sustained Attention/Vigilance and Negativity. These factors strongly predicted poorer social functioning in FES, along with poorer quality of life in psychological, social, and health satisfaction facets. CONCLUSION: The IntegNeuro battery has utility for assessing separable domains of general and social cognition in FES, which are predictive of real world outcomes. Thus, it may be appropriate for clinical application, including in multi-center trials targeting new treatments for cognition in schizophrenia.     

1-year follow-up study of cognitive function in first-episode non-affective psychosis

The longitudinal course of primary cognitive dysfunction seen in schizophrenia has yet to be fully clarified. Whereas some studies in chronic patients have revealed a progressive decline in cognitive abilities, those studies with first-episode patients have indicated that initial cognitive deficits might remain stable over time. The aim of this study was to examine the longitudinal course of cognitive functioning in patients with a first episode of schizophrenia. 112 patients with a first episode of schizophrenia-spectrum disorders and 22 healthy controls completed clinical and cognitive evaluations at baseline and again after 1 year. An extensive neuropsychological battery that comprised seven cognitive domains was used. Patients and controls improved their cognitive performance in virtually all the cognitive domains after one year. However, patients continued to show marked cognitive deficits after one year, unlike healthy volunteers. The longitudinal cognitive changes were similar in patients and controls in all domains except Verbal Memory (F = 11.67; df = 1; P = 0.001). The increase in cognitive scores found during early phases of the illness seems to be associated to practice-related changes and would not reflect a real cognitive enhancement but rather stability of deficit. Patients' deficits remained stable over time in all cognitive domains except Verbal Memory, in which less performance improvement was found. Further investigations are warranted to discern the variability in patterns of specific cognitive deficits over time.     

The MATRICS Consensus Cognitive Battery, part 1: test selection, reliability, and validity

OBJECTIVE: The lack of an accepted standard for measuring cognitive change in schizophrenia has been a major obstacle to regulatory approval of cognition-enhancing treatments. A primary mandate of the National Institute of Mental Health's Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) initiative was to develop a consensus cognitive battery for clinical trials of cognition-enhancing treatments for schizophrenia through a broadly based scientific evaluation of measures. METHOD: The MATRICS Neurocognition Committee evaluated more than 90 tests in seven cognitive domains to identify the 36 most promising measures. A separate expert panel evaluated the degree to which each test met specific selection criteria. Twenty tests were selected as a beta battery. The beta battery was administered to 176 individuals with schizophrenia and readministered to 167 of them 4 weeks later so that the 20 tests could be compared directly. RESULTS: The expert panel ratings are presented for the initially selected 36 tests. For the beta battery tests, data on test-retest reliability, practice effects, relationships to functional status, practicality, and tolerability are presented. Based on these data, 10 tests were selected to represent seven cognitive domains in the MATRICS Consensus Cognitive Battery. CONCLUSIONS: The structured consensus method was a feasible and fair mechanism for choosing candidate tests, and direct comparison of beta battery tests in a common sample allowed selection of a final consensus battery. The MATRICS Consensus Cognitive Battery is expected to be the standard tool for assessing cognitive change in clinical trials of cognition-enhancing drugs for schizophrenia. It may also aid evaluation of cognitive remediation strategies.     

Cognitive functioning related to quality of life in schizophrenia

The present study compared the cognitive function of patients with schizophrenia to that of healthy subjects, and investigated the relationships between cognitive function and quality of life (QOL). Participants consisted of 53 patients meeting DSM-IV criteria for schizophrenia and 31 normal controls. All participants completed a neuropsychological test battery assessing executive function, verbal memory, and social knowledge. QOL was rated using the Schizophrenia Quality of Life Scale. Patients with schizophrenia showed lower performance across various cognitive measures of memory, including the Sentence Memory Test, the Verbal Learning Test, and the Script Test, as well as the Rule Shift Cards Test of executive function. Multiple regression analyses were used to evaluate the neuropsychological measures and clinical symptoms to predict QOL. The QOL total score, the social initiative score or the empathy score were significantly predicted by the Script or/and the Sentence Memory. Neuropsychological functioning was unrelated to most QOL scores in the presence of clinical symptoms, while ability of empathy in the QOL was predicted by performance of the Sentence Memory Test. These results demonstrated patients with schizophrenia have deficits in executive function, memory and learning, and social knowledge, and that social knowledge and memory are related to QOL. Thus, in patients with schizophrenia, deficits in social knowledge appear to be associated with current QOL in general, and specifically with the capacity for empathy and social initiative.     

Approaching a consensus cognitive battery for clinical trials in schizophrenia: the NIMH-MATRICS conference to select cognitive domains and test criteria.

To stimulate the development of new drugs for the cognitive deficits of schizophrenia, the National Institute of Mental Health (NIMH) established the Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) initiative. This article presents an overview of decisions from the first MATRICS consensus conference. The goals of the meeting were to 1) identify the cognitive domains that should be represented in a consensus cognitive battery and 2) prioritize key criteria for selection of tests for the battery. Seven cognitive domains were selected based on a review of the literature and input from experts: working memory, attention/vigilance, verbal learning and memory, visual learning and memory, reasoning and problem solving, speed of processing, and social cognition. Based on discussions at this meeting, five criteria were considered essential for test selection: good test-retest reliability, high utility as a repeated measure, relationship to functional outcome, potential response to pharmacologic agents, and practicality/tolerability. The results from this meeting constitute the initial steps for reaching a consensus cognitive battery for clinical trials in schizophrenia.     

癫(癎)患者认知功能特点的研究

目的:研究癫(EP)患者认知功能的特点及其影响因素。方法:采用听觉词语测验、逻辑记忆测验、数字符号转换测验、Stoop字色干扰测验、连线测验、言语流畅性测验、Rey-Osterrieth复杂图片测验及Boston命名测验对166例EP患者进行认知评定。结果:EP患者存在广泛的认知损害,包括言语记忆、情景记忆、视觉空间结构记忆、词语学习能力、注意力、抗干扰能力、精神运动速度及言语命名功能等方面,以词语延迟回忆、注意力及精神运动速度损害最为明显。而未经药物干预的新诊断EP患者已存在除视觉空间记忆、注意力及抗干扰能力外的上述认知功能的损害,以词语延迟回忆最为明显。随访病例与新诊断病例的区别在于,前者在抗干扰能力及精神运动速度方面损害更明显。结论:新诊断EP组以及随访EP组病例在多项神经心理学测验中得分均低于正常对照组,两组之间差异有统计学意义。     

Mayo's older African American normative studies: confirmatory factor analysis of a core battery.

Covariance structure analyses of a core neuropsychological test battery consisting of the Wechsler Adult Intelligence Scale-Revised, Wechsler Memory Scale-Revised, and Auditory Verbal Learning Test have previously identified a 5-factor model in a sample of cognitively normal White volunteers from Mayo's Older Americans Normative Studies (MOANS). The present study sought to replicate this factor structure in a sample of 289 cognitively normal, community-dwelling African American elders from Mayo's Older African Americans Normative Studies (MOAANS). The original 5-factor model was tested against 2 alternative 4-factor models and a 6-factor model generated on a substantive basis. Confirmatory factor analysis supported the construct validity of this core battery in older African Americans by replicating the original 5-factor model of Verbal Comprehension, Perceptual Organization, Attention/Concentration, Learning, and Retention as viable in the present sample.     

Neuropsychological performance in schizotypal personality disorder: importance of working memory

BACKGROUND: Cognitive deficits consistently have been reported in schizophrenia patients and in patients with schizotypal personality disorder. For this study, the authors wanted to identify which of the domains of cognitive impairment represent "core" deficits of schizophrenia, comparing subjects with schizotypal personality disorder to two comparison groups: healthy volunteers and patients with personality disorders unrelated to schizophrenia. METHOD: Three groups completed a neuropsychological battery: patients with DSM-III-R schizotypal personality disorder (N=82); patients with DSM-III-R personality disorders unrelated to schizophrenia (i.e., a personality disorder other than schizotypal, schizoid, or paranoid [N=44]); and healthy volunteers (N=63). The battery included the California Verbal Learning Test, Trailmaking Test parts A and B, the Dot test of working memory, the Stroop Color and Word Test, the Paced Auditory Serial Addition Test, the WMS visual reproduction test, and the WAIS-R vocabulary and block design. RESULTS: Normative standards for performance that controlled for age, gender, and education were created from the scores of the healthy volunteers. Overall, schizotypal personality disorder patients performed significantly worse than the healthy volunteers and those with personality disorders unrelated to schizophrenia. Specifically, patients with schizotypal personality disorder demonstrated impaired performance on the Paced Auditory Serial Addition Test, WMS visual reproduction test, Dot test, and California Verbal Learning Test. In addition, in a regression analysis, performance on the Paced Auditory Serial Addition Test demonstrated the largest effect size. Indeed, it accounted for unique variance above and beyond all other cognitive measures, since controlling for Paced Auditory Serial Addition Test performance abolished group differences across all other measures. CONCLUSIONS: Patients with schizotypal personality disorder demonstrated moderate cognitive impairment compared with healthy volunteers (significant for seven out of 11 measures). These differences reached statistical significance for tasks of working memory, episodic memory, and delayed recall. Working memory performance accounted for the group differences. This study supports the view that working memory represents a core deficit of schizophrenia spectrum disorders.     

Serological evidence of exposure to Herpes Simplex Virus type 1 is associated with cognitive deficits in the CATIE schizophrenia sample

Cognitive impairment is a core feature of schizophrenia. Previous studies have indicated that exposure to neurotropic infectious agents such as Herpes Simplex Virus type 1 may contribute to cognitive deficits and neuroanatomical abnormalities in individuals with schizophrenia. We examined the association between exposure to neurotropic infectious agents and cognitive function in 1308 participants in the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) trial. This sample included all of the individuals in the CATIE trial for whom baseline blood samples were available. Cognition was evaluated at baseline by a test battery which yielded composite scores in the domains of processing speed, verbal memory, vigilance, reasoning, and working memory as well as a summary neurocognitive score. Solid phase immunoassay techniques were used to measure IgG class antibodies to Herpes Simplex Virus type 1 (HSV-1), Herpes Simplex Virus type 2 (HSV-2), Cytomegalovirus (CMV), and to Toxoplasma gondii (T gondii) in the sera of the study individuals. We found a significant association between the neurocognitive summary score and antibodies to HSV-1 but not to HSV-2, CMV, or T. gondii. There was also a significant association between HSV-1 exposure and the Verbal Memory, Vigilance, and Processing Speed composite scores. HSV-1 may modulate the neurocognitive function of individuals with schizophrenia through its ability to establish latency in the central nervous system and undergo periodic reactivation. A better understanding of the role of HSV-1 may lead to better methods of treatment for the cognitive impairments associated with schizophrenia.     

Stimulating development of new drugs to improve cognition in schizophrenia

Cognitive deficits are core features of schizophrenia that are critical determinants of poor functional outcome. Until recently, the development of novel pharmacologic treatments that specifically target these deficits has been impeded by a lack of consensus about which domains of cognition should be covered and how they should be measured in clinical trials. The National Institute of Mental Health Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) Initiative was designed to overcome these barriers by creating a consensus-based pathway through which procognitive compounds can ultimately attain regulatory approval. This review summarizes the rationale for the MATRICS Initiative, some of its achievements to date, and promising pharmacologic targets for the cognitive deficits of schizophrenia.     

Intelligence or years of education: which is better correlated with memory function in normal elderly Japanese subjects?

Background: We compared differences in intelligence and memory function between normal elderly Japanese subjects with more years of education and those with fewer years of education. We also investigated clinical and neuropsychological factors that are strongly correlated with memory function. Methods: There were 118 normal elderly subjects who underwent the Mini‐Mental State Examination, Wechsler Adult Intelligence Scale, 3rd edition (WAIS‐III), and Wechsler Memory Scale Revised. Subjects with at least 13 years of education were categorized as the H group, and those with 12 years of education or less were categorized as the L group. Results: Age and Mini‐Mental State Examination scores were not significantly different between the two groups. On the WAIS‐III, there were significant differences between the two groups in Verbal IQ and Full Scale IQ. On the Wechsler Memory Scale Revised, there were significant differences between the two groups in Visual Memory, General Memory, and Delayed Recall. Correlation coefficients between memory function and the other factors demonstrated significant but weak correlations between years of education and General Memory (R = 0.22) and between years of education and Delayed Recall (R = 0.20). Strong correlations were found between Verbal IQ and Verbal Memory (R = 0.45), between Verbal IQ and General Memory (R = 0.49), between Full Scale IQ and General Memory (R = 0.50) and between Full Scale IQ and Delayed Recall (R = 0.48). Conclusions: In normal elderly Japanese subjects, years of education weakly correlated with memory function while Verbal IQ, Full Scale IQ and Verbal Comprehension on WAIS‐III had stronger correlations with memory function. Verbal IQ and Verbal Comprehension on WAIS‐III were found to be insusceptible to the cognitive decline characteristic of Alzheimer's disease or amnestic mild cognitive impairment. Therefore, verbal intelligence, as measured by Verbal IQ and Verbal Comprehension, may be the most useful factor for inferring premorbid memory function in Alzheimer's disease or amnestic mild cognitive impairment patients.     

Dimensions of Cognitive Ability in Dementia: Differential Sensitivity to Degree of Impairment in Alzheimer's Disease

The purpose of this study was to identify dimensions of cognitive functioning in demented elderly persons and examine sensitivity of these dimensions to different degrees of cognitive impairment in Alzheimer's disease. Participants included 210 demented elderly patients and 89 normal controls. Principal components analysis of neuropsychological test scores for the demented patients yielded the following six components: (1) Memory/Learning, (2) Spatial/Nonverbal, (3) Verbal/Lexical Knowledge, (4) Verbal Fluency, (5) Visual Paired Associates, and (6) Verbal Attention Span. All dimensions discriminated among normal controls and three groups of patients with probable Alzheimer's disease defined by decreasing Mini-Mental State Exam scores. Differential sensitivity of cognitive dimensions was observed as a function of level of cognitive impairment.     

Memory performance of geriatric and nongeriatric chronic schizophrenic patients: a cross-sectional study.

Memory functioning has been studied extensively in nongeriatric schizophrenic patients, leading to the suggestion that schizophrenic patients manifest a "subcortical" pattern of memory deficits. Few previous studies examined very poor outcome patients with a chronic course of hospitalization. This study examined the association of age and global cognitive dysfunction with verbal and spatial learning and delayed recall, as well as examining differential impairments in delayed recall as compared to delayed recognition memory. Sixty-six chronic schizophrenic patients were studied, with 30 of these patients over the age of 65. Verbal (California Verbal Learning Test) and spatial (Biber Figure Learning Test) serial learning and delayed memory tests were administered. All aspects of memory functioning were correlated with estimates of global cognitive status. When global cognitive status was controlled, age effects were still found for the majority of the memory measures. Delayed recognition memory was not spared, being performed as poorly as delayed recall. In contrast to previous studies of better-outcome patients with schizophrenia, geriatric patients with chronic schizophrenia performed more poorly than nongeriatric patients. The lack of sparing of delayed recognition memory suggests that previous findings of specific recall memory deficit and a subcortical profile of memory impairments may apply to schizophrenic patients with less severe global cognitive impairments. These data suggest that poor-outcome patients may have a pattern of memory impairments that has some features in common with cortical dementia.     

A new window on neurocognitive dysfunction in the childhood form of myotonic dystrophy type 1 (DM1)

Not much is known about the neurocognitive deficits in the childhood phenotypic expression of DM1. Twenty-four children and adolescents with no mental retardation were administered an extensive neuropsychological battery to investigate cognition in terms of memory, executive functions and visuo-spatial abilities. The results showed discrepancies between Wechsler’s indexes with higher scores in Verbal Comprehension than Perceptive Organization and Speed of Processing. Memory assessment using Signoret’s Memory Battery revealed a clear difference between verbal and visuospatial memory but no impairment between short and long-term memory. Concerning executive abilities, DM1 subjects showed greater deficits in processing speed than in mental flexibility, inhibition or working memory. This pattern of deficits could implicate a frontoparietal circuit in accordance with the neural networks involved in the adult form of DM1 and reopens the question of a continuum between childhood and adulthood neurocognitive impairments.     

精神分裂症首次发病患者及其健康同胞认知功能的比较研究

目的 比较精神分裂症首次发病患者与健康同胞及正常对照认知功能的差异,探讨精神分裂症在认知功能领域的内表型.方法 采用目前常用的范畴流畅测验(CFT)、数字符号编码测验(DSCT)、连线测验(TMT)、韦克斯勒记忆量表第3版(WMS-Ⅲ)空间广度测验(WMS-ⅢSST)、霍普金斯词汇学习测验-修订版(HVLT-R)、简易视觉空间记忆测验-修订版(BVMT-R)、定步调听觉连续加法测验(PASAT)和威斯康星卡片分类测验-64(WCST-64)对92例精神分裂症首次发病患者(患者组)、56例健康同胞(同胞组)和62名健康对照者(对照组)的认知功能进行检测.结果 (1)患者组所有神经心理测验成绩均差于对照组,差异有统计学意义(P＜0.01).(2)同胞组的CFT、DSCT、TMT、HVLT-R即刻记忆和延迟记忆、BVMT-R即刻记忆、PASAT、WCST-64持续错误数、持续反应数和完成分类数的测验成绩差于对照组,差异有统计学意义(P＜0.05).(3)患者组与同胞组的CFT、WCST-64中的持续错误数、持续反应数和完成分类数测验成绩分别为(18.40±12.12)分比( 18.86±5.19)分、(16.48±8.19)分比(14.80±5.86)分、(18.76±10.91)分比(16.86 ±7.73)分、(1.33±2.81)分比(1.63±1.36)分,2组比较差异无统计学意义(P＞0.05),其他神经心理测验成绩比较,患者组差于同胞组,差异有统计学意义(P＜0.05).结论 精神分裂症首次发病患者存在处理速度、工作记忆、言语记忆、空间记忆、注意警觉和执行功能广泛性的认知功能损害,精神分裂症健康同胞存在处理速度、言语记忆、视觉记忆、注意警觉、执行功能的认知缺陷;语义流畅性功能和执行功能可能是精神分裂症的潜在内表型.     

Impairment of verbal memory and learning in antipsychotic-naïve patients with first-episode schizophrenia

BACKGROUND: Verbal memory deficits are of interest in schizophrenia because of the potential relationship to functional and anatomic mesial temporal lobe pathology in this disorder. The goal of this study was to characterize the nature of verbal memory impairments in antipsychotic-na?ve schizophrenic patients early in the course of illness. METHODS: Neuroleptic-na?ve patients with schizophrenia (n=62) and healthy individuals (n=67), matched on IQ, age, sex, and parental socioeconomic status, were administered the California Verbal Learning Test (CVLT). RESULTS: Schizophrenia participants performed significantly worse than healthy individuals on measures of verbal learning, short- and long-term memory, and immediate attention. Deficits in recall were related to reduced use of organizational strategies to facilitate verbal encoding and retrieval. No group differences were found in rate of forgetting or susceptibility to proactive or retroactive interference. Memory deficits had minimal relation to positive or negative symptom severity. CONCLUSIONS: Schizophrenia is characterized by significant verbal memory dysfunction early in the course of illness prior to treatment with antipsychotic medications. Deficits in consistency of learning over several trials, as well as a strong relationship between semantic organizational strategies and reduced learning capacity, implicate prefrontal dysfunction as a contributor to verbal memory deficits in schizophrenia.     

Prefrontal Brain Network Connectivity Indicates Degree of Both Schizophrenia Risk and Cognitive Dysfunction

Objective:

Cognitive dysfunction is a core feature of schizophrenia, and persons at risk for schizophrenia may show subtle deficits in attention and working memory. In this study, we investigated the relationship between integrity of functional brain networks and performance in attention and working memory tasks as well as schizophrenia risk.

Methods:

A total of 235 adults representing 3 levels of risk (102 outpatients with schizophrenia, 70 unaffected first-degree relatives of persons with schizophrenia, and 63 unrelated healthy controls [HCs]) completed resting-state functional magnetic resonance imaging and a battery of attention and working memory tasks (Brief Test of Attention, Hopkins Verbal Learning Test, and Brief Visuospatial Memory Test) on the same day. Functional networks were defined based on coupling with seeds in the dorsal anterior cingulate cortex, dorsolateral prefrontal cortex (DLPFC), medial prefrontal cortex (MPFC), and primary visual cortex. Networks were then dissected into regional clusters of connectivity that were used to generate individual interaction matrices representing functional connectivity within each network.

Results:

Both patients with schizophrenia and their first-degree relatives showed cognitive dysfunction compared with HCs. First canonicals indicated an inverse relationship between cognitive performance and connectivity within the DLPFC and MPFC networks. Multivariate analysis of variance revealed multivariate main effects of higher schizophrenia risk status on increased connectivity within the DLPFC and MPFC networks.

Conclusions:

These data suggest that excessive connectivity within brain networks coupled to the DLPFC and MPFC, respectively, accompany cognitive deficits in persons at risk for schizophrenia. This might reflect compensatory reactions in neural systems required for cognitive processing of attention and working memory tasks to brain changes associated with schizophrenia.Key words: resting state, fMRI, default-mode network, attention, working memory     

Neuropsychological and oculomotor correlates of spatial working memory performance in schizophrenia patients and controls.

Recent reports of spatial working memory deficits in schizophrenia provide evidence for dorsolateral prefrontal cortical (DLPFC) dysfunction. However, the question of how spatial working memory performance relates to other task impairments in schizophrenia considered reflective of frontal dysfunction, such as the Wisconsin Card Sorting Test (WCST) and smooth pursuit eye tracking, has been largely unexplored. Spatial working memory, as measured by a computerized visual-manual delayed response task (DRT), was evaluated in 42 schizophrenia patients and 54 normal controls. Subjects also completed a battery of neuropsychological and oculomotor tasks. Schizophrenia patients performed as accurately as controls on a no-delay, sensory-motor control condition, but showed a significant impairment in spatial accuracy with the addition of an 8-s delay and verbal distraction task. For the patients, working memory impairment was associated with fewer categories on the WCST, impaired eye tracking, fewer words learned on the Rey Auditory Verbal Learning Test, but not with measures of general cognitive and clinical functioning. Results suggest the presence of a sub-group of schizophrenia patients with common pathophysiology that accounts for the co-variance of several tasks implicating prefrontal dysfunction.     

Emotional discomfort and impairments in verbal memory in schizophrenia

Research has demonstrated that impairments in verbal memory in schizophrenia are linked with psychosocial deficits. Less is known, however, about their relationship to clinical features of illness. This study explores the hypothesis that impairments in verbal memory, particularly forms of memory requiring deeper levels of encoding, are uniquely linked to symptoms of dysphoria or emotional discomfort. Accordingly, we examined the association between concurrent measures of symptoms and verbal memory for 84 subjects with schizophrenia. Measures of positive, negative, cognitive, excitement and emotional discomfort symptoms were derived from factor scores of the Positive and Negative Syndrome Scale. Verbal memory was assessed using two tests requiring relatively superficial levels of encoding: The Hopkins Verbal Memory Test and the Digit Span subtest; and one test requiring deeper levels of encoding: the Logical Memory subtests I and II. As predicted, multiple regressions controlling for age, education and attention revealed that poorer performance on Logical Memory was strongly associated with greater levels of emotional discomfort (R(2)=0.22 and 0.25, respectively) while performance on the Hopkins test was related to cognitive symptoms scores (R(2)=0.08 and 0.09, respectively). Implications for the conceptualization of verbal memory deficits in schizophrenia are discussed.     

Neuropsychological performance in schizotypal personality disorder: evidence regarding diagnostic specificity.

BACKGROUND: Individuals with schizotypal personality disorder (SPD) share cognitive deficits with schizophrenic patients, suggesting that these deficits represent a core feature of the schizophrenia spectrum. We investigated the neuropsychological profile in SPD patients compared with two comparison groups: healthy volunteers (HV) and patients who met criteria for another non-schizophrenia spectrum personality disorder (NSS). METHODS: We tested 48 DSM-III-R SPD patients, 22 NSS and 32 HV on a neuropsychologic battery that included the California Verbal Learning Test (CVLT), Trail Making A and B, the DOT test of working memory, the Stroop Color-Word Interference, the Paced Auditory Serial Addition Test (PASAT), the Wechsler Memory Scale Visual Reproduction Test (WMSV-R), and the Wechsler Adult Intelligence Scale vocabulary and block design. RESULTS: Normative standards for performance were created using the HV group. SPD patients performed significantly worse compared with HVs; specifically, SPD patients demonstrated impaired performance on the PASAT and the WMSV-R immediate and delayed recall compared to HV. Moreover, SPD patients were impaired in the PASAT and the WMSV-R immediate condition compared with the NSS group. The NSS patients did not differ from HV on any of the cognitive tasks. The interpersonal factor of the schizotypal symptoms inversely correlated with the PASAT score (r = -.32, p <.006). CONCLUSIONS: Compared with HVs, SPD patients demonstrate modest cognitive impairment. These differences reached statistical significance for the PASAT (an auditory working memory task), and the WMSV-R immediate and delayed recall (a learning-recall test). In contrast, performance of NSS patients did not differ from that of HVs. The types of deficits observed in SPD patients are qualitatively similar to but milder than those seen in patients with schizophrenia.