Neurocognitive profile in adolescents with early-onset schizophrenia: clinical correlates.

BACKGROUND: Neurocognitive impairments have been documented in adolescents with early-onset schizophrenia (EOS; onset by age 18) and are important treatment targets. Information concerning the severity, pattern, and clinical correlates of these deficits in EOS remains limited. METHODS: Tests assessing motor skills, attention, memory, visuospatial abilities and executive functioning were administered to 54 clinically stabilized adolescents with EOS and 52 age- and sex-matched healthy controls. Childhood-onset patients (onset by age 13) were compared to those with an adolescent onset of illness. Patients' neurocognitive profiles were compared to those of controls. Relationships between neurocognitive deficits and demographic and clinical characteristics were explored. RESULTS: Neurocognitive profiles did not differ between childhood- and adolescent-onset participants. Patients showed a generalized neurocognitive deficit of 2.0 SDs compared to controls, with relative deficit in executive functioning and relative sparing of language and visuospatial abilities. Degree of generalized neurocognitive impairment was associated with premorbid adjustment and negative symptom severity (Adjusted R(2) = .39). CONCLUSIONS: Results document both a significant generalized deficit and a relative deficit of executive functioning in adolescents with EOS. The overall pattern is similar to that observed in severely ill first-episode adult patients. The impairments across multiple neurocognitive domains suggest widespread brain dysfunction in EOS.     

Self-rated and performance-based empathy in schizophrenia: The impact of cognitive deficits

People may be much less empathic than they think they are. It is not clear whether patients with schizophrenia who have impaired empathic abilities also exhibit diminished ability to accurately appraise their own such skills. The present study aimed to examine: (a) the accuracy of self-appraisal of empathy and (b) the impact of specific cognitive functions on both self-rated and performance-based empathy in schizophrenia patients and healthy volunteers. Self-reported empathy and performance-based empathy were assessed in 52 chronic patients with schizophrenia and 45 matched healthy participants with the empathy quotient and the empathy score in the Faux Pas test, respectively. Neuropsychological functioning and symptom severity were also assessed. No significant correlations between self-reported and performance-based empathy scores were found in patients, whereas these correlations were significant and positive in the control group, with the exception of Faux Pas recognition. Cognitive deficits, specifically in processing speed and theory of mind, negatively affected performance-based but not self-rated empathy in schizophrenia. Patients with less negative and more positive symptoms and lower set shifting ability reported higher empathic abilities. Self-reported empathy and empathic abilities do not show a simple relationship. Our findings highlight a double deficit related to empathic responding in schizophrenia: diminished performance associated with cognitive deficits and inaccurate self-appraisal of empathic abilities.     

Depression and cognitive deficits in geriatric schizophrenia

Objective

Past reports have found patients with comorbid depression and schizophrenia spectrum disorders exhibit greater deficits in memory and attention compared to schizophrenia spectrum disorder patients without depressive symptoms. However, in contrast to younger schizophrenia patients, the few past studies using cognitive screens to examine the relationship between depression and cognition in inpatient geriatric schizophrenia have found that depressive symptomatology was associated with relatively enhanced cognitive performance. In the current study we examined the relationship between depressive symptoms and cognitive deficits in geriatric schizophrenia spectrum disorder patients (n = 71; mean age = 63.7) on an acute psychiatric inpatient service.

Method

Patients completed a battery of cognitive tests assessing memory, attention and global cognition. Symptom severity was assessed via the PANSS and Calgary Depression Scale for Schizophrenia.

Results

Results revealed that geriatric patients' depression severity predicted enhancement of their attentional and verbal memory performance. Patients' global cognitive functioning and adaptive functioning were not associated with their depression severity.

Conclusion

Contrary to patterns typically seen in younger patients and non-patient groups, increasing depression severity is associated with enhancement of memory and attention in geriatric schizophrenia spectrum disorder patients. Also, diverging from younger samples, depression severity was unassociated with patients adaptive and global cognitive functioning.     

Defining a cognitive function decrement in schizophrenia.

BACKGROUND: Although cognitive impairment is described as a core component of the characterization of schizophrenia, a sizable percentage of patients are classified as unimpaired by traditional definitions of impairment. The purpose of this study was to determine the percentage of patients with schizophrenia meeting criteria for a "cognitive function decrement" defined as a current level of cognitive function that falls below the level predicted by premorbid estimates. METHODS: Linear regression analyses were performed on a healthy control population to determine a predicted composite cognitive score based on maternal education, paternal education, and reading score as indicators of premorbid intellectual function. The percentages of patients with current cognitive function above and below predicted values were calculated. RESULTS: When the Wide Range Achievement Test-3 (WRAT-3) score and maternal education are both used to predict current cognitive performance, as expected, about half (42%) of control subjects fall below expectations. However, 98.1 % of patients fall below expectations. CONCLUSIONS: When cognitive function decrement is defined as a failure to reach the expected level of cognitive functioning, almost all patients with schizophrenia meet this definition.     

Generalized and specific neurocognitive deficits in prodromal schizophrenia.

BACKGROUND: Neurocognitive deficits are considered to be central to the pathophysiology of schizophrenia, and the neurodevelopmental model suggests that such deficits precede full-blown psychosis. The present study examined performance on a broad neuropsychological battery of young subjects considered to be at clinical high risk for schizophrenia, who were subsequently followed to determine clinical outcome. METHODS: Subjects were 38 clinical high-risk patients (58% male patients; mean age = 16.5) and 39 sex- and age-matched healthy control subjects. At baseline, all high-risk patients had attenuated (subpsychotic) schizophrenialike positive symptoms. Clinical follow-up data of at least 6 months duration was available on 33 patients, of whom 12 developed nonaffective psychotic disorders. RESULTS: At baseline, clinical high-risk patients had significantly impaired global cognitive performance relative to control subjects and to estimates of their own prior intellectual functioning. Measures of verbal memory and executive functioning/working memory showed significantly greater impairments; visuospatial functioning was relatively spared. Prodromal patients who later developed psychosis had significantly lower verbal memory scores at baseline compared with patients who remained nonpsychotic. CONCLUSIONS: Verbal memory deficits may be an important risk marker for the development of schizophrenia-spectrum psychotic disorders, possibly indicating the presence of a prefrontal-hippocampal neurodevelopmental abnormality. Generalized neurocognitive impairment may be a nonspecific vulnerability marker.     

The relationship of structural alterations to cognitive deficits in schizophrenia: a voxel-based morphometry study.

BACKGROUND: Region of interest studies have identified a number of structure-cognition associations in schizophrenia and revealed alterations in structure-cognition relationship in this population. METHODS: We examined the relationship of structural brain alterations, identified using voxel-based morphometry, to cognitive deficits in 45 schizophrenia patients relative to 43 healthy control subjects and tested the hypothesis that structure-cognition relationship is altered in schizophrenia. RESULTS: Patients had smaller total brain, gray matter, and white matter volumes. Regional alterations were left-hemisphere specific, including: gray matter reduction of inferior frontal, lingual, and anterior superior temporal gyri; white matter reduction of posterior and occipital lobes; and gray matter increase of the putamen and the precuneus. Smaller whole brain and gray matter volumes were associated with lower premorbid intelligence quotient (IQ) and poorer performance on IQ-dependent cognitive measures in patients and to a similar extent in control subjects. Larger precuneus was associated with better immediate verbal memory in patients, whereas verbal and nonverbal memory were positively associated with inferior frontal gyrus volume in control subjects. Smaller occipital white matter volume was associated with slower information processing speed in patients but not in control subjects. CONCLUSIONS: Regional volume alterations are associated with specific cognitive deficits in schizophrenia. Some structure-cognition relationships differentiate this population from healthy control subjects.     

精神分裂症的记忆功能及其影响因素

目的了解精神分裂症患者的记忆功能及其影响因素。方法对100例精神分裂症患者及64例正常对照进行韦氏记忆量表(WMS)评定,同时调查患者的临床特征。结果精神分裂症患者的记忆商(MQ)以及1→100、100→1、累加、图片、联想评分均显著低于正常对照,患者记忆障碍的发生率为61%。单因素分析显示,MQ与病程呈负相关,与发病年龄呈正相关,与精神病性症状、所使用的抗精神病药类型、疾病分型等因素无关。多元逐步回归分析显示,仅病程与MQ有关。结论精神分裂症的记忆损害是原发的、广泛的,可能与病程有关。     

Factors mediating cognitive deficits and psychopathology among siblings of individuals with schizophrenia

Schizotypal traits and cognitive disturbances are known to be present in first-degree relatives of people with schizophrenia. However, there is little understanding of how these endophenotypes are related to each other. We explored the nature of this relationship in individuals with schizophrenia, their full siblings, community controls, and their siblings. All participants were assessed in the domains of working memory, attention, episodic memory, and executive function, as well as in their level of positive, negative, and disorganization symptoms. Schizophrenia probands were significantly impaired on all cognitive domains, as compared with the other 3 groups, and displayed the highest levels of positive, negative, and disorganization symptoms. Proband siblings performed significantly worse than controls on tasks of working memory, episodic memory, and executive function, and they displayed significantly more positive and negative symptoms as compared with controls. Poorer task performance across all 4 cognitive domains was most strongly correlated with increased negative symptoms. Mediation analyses revealed that working memory, episodic memory, and executive function deficits partially mediated increases in negative symptoms among proband siblings. Negative symptoms fully mediated deficits in working memory and episodic memory but only partially mediated deficits in executive function. Results suggest that there is a complex relationship between cognitive and clinical factors in this high-risk population.     

How specific are deficits in mismatch negativity generation to schizophrenia?

BACKGROUND: Mismatch negativity (MMN) is an auditory event-related potential that provides an index of auditory sensory memory. Deficits in MMN generation have been repeatedly demonstrated in chronic schizophrenia. Their specificity to schizophrenia has not been established. METHODS: Mismatch negativity to both duration and frequency deviants was investigated in gender- and age-matched patients with schizophrenia or schizoaffective disorder (n = 26), bipolar disorder (n = 16), or major depression (n = 22) and healthy control subjects (n = 25). RESULTS: Only patients with schizophrenia demonstrated significantly smaller mean MMN than did healthy control subjects. Detailed analyses showed significantly smaller MMN to both duration and frequency deviants in patients with schizophrenia than in healthy control subjects; however, the reduction of frequency MMN in patients with schizophrenia was not significant in the comparison across all groups. Mismatch negativity topography did not differ among groups. No consistent correlations with clinical, psychopathologic, or treatment variables were observed. CONCLUSIONS: Mismatch negativity deficits, and by extension deficits in early cortical auditory information processing, appear to be specific to schizophrenia. Animal and human studies implicate dysfunctional N-methyl-D-aspartate receptor functioning in MMN deficits. Thus MMN deficits may become a useful endophenotype to investigate the genetic underpinnings of schizophrenia, particularly with regard to the N-methyl-D-aspartate receptor.     

认知矫正治疗慢性精神分裂症患者认知功能缺陷的随机对照研究

目的 探讨认知矫正治疗(CRT)和计算机认知矫正治疗(CCRT)对精神分裂症患者认知缺陷的疗效.方法 180例慢性期病情稳定的精神分裂症患者随机分成3组,CCRT组、CRT组和工娱治疗(WAT)组.CCRT组108例,治疗以自主开发的计算机认知矫正治疗系统为工具,每周4次,每次45 min,持续3个月;CRT组36例,以Ann Delahunty和Rodney Morice等制定的神经认知矫正手册(汉化)为治疗工具,在治疗师的指导下进行认知矫正治疗;WAT组36例,接受相同时间的工娱治疗.3组在治疗频度和治疗持续时间上完全一致.治疗前后及治疗结束后第3个月分别进行临床症状和认知功能评定,内容包括阳性和阴性症状量表(PANSS)、精神分裂症认知功能成套测验(MCCB)、威斯康星卡片分类测验(WCST).结果 治疗结束后及随访第3个月时,CCRT组和CRT组在改善WCST完成分类数、连线测验、空间广度方面显著优于WAT组(P均＜0.05);CCRT组在空间广度方面明显优于CRT组(P＜0.05),CRT组在符号编码方面则优于CCRT组(P＜0.05);3组的临床症状在治疗结束及随访阶段无明显变化.结论 CCRT和CRT均能显著改善慢性精神分裂症患者的认知功能,主要表现在记忆、执行功能、精神运动速度方面;CCRT在空间记忆方面较CRT有优势,CRT在精神运动方面较CCRT有优势,CCRT和CRT在执行功能、记忆、精神运动速度等方面的疗效能持续3个月.     

Association of cognitive and P50 suppression deficits in chronic patients with schizophrenia

ObjectiveCognitive deficits are core symptoms of schizophrenia; however, their pathophysiological mechanisms are still unclear. A sensory gating deficit, as reflected by P50 suppression, has been repeatedly shown in schizophrenia patients, which may be associated with cognitive deficits in this disorder. The present study was to examine the relationship between the P50 suppression and cognitive deficits in patients with schizophrenia, which is still under-investigated.MethodWe recruited 38 chronic schizophrenia patients and 32 matched healthy controls, and assessed their cognition with the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and P50 suppression with the electroencephalography system.ResultsThe total and its 4 index scores (all p < 0.05) except for the visuospatial/ constructional index of RBANS were significantly lower in patients compared with healthy controls. However, only the language and attention passed Bonferroni corrections. Patients displayed a significantly higher P50 ratio, higher S2 amplitude, and lower S1 amplitude (all p < 0.05) than healthy controls. Interestingly, only in the patients, the S1 amplitude was associated with both language and attention, and the S2 amplitude with both visuospatial/ constructional and language (all p < 0.05), although all of these significances did not pass the Bonferroni corrections. The P50 ratio was not associated with any of the RBANS scores (all p > 0.05).ConclusionsOur results suggest the P50 suppression deficits in Chinese patients with schizophrenia, which may be associated with cognitive impairments of this illness. Moreover, the amplitude of S1 and the amplitude of S2 may be involved in the different cognitive domain deficits in schizophrenia patients.SignificanceThis study suggests that the P50 components may possibly be effective biomarkers for cognitive deficits in patients with schizophrenia.     

Orienting to social stimuli differentiates social cognitive impairment in autism and schizophrenia

Both autism and schizophrenia feature deficits in aspects of social cognition that may be related to amygdala dysfunction, but it is unclear whether these are similar or different patterns of impairment. We compared the visual scanning patterns and emotion judgments of individuals with autism, individuals with schizophrenia and controls on a task well characterized with respect to amygdala functioning. On this task, eye movements of participants are recorded as they assess emotional content within a series of complex social scenes where faces are either included or digitally erased. Results indicated marked abnormalities in visual scanning for both disorders. Controls increased their gaze on face regions when faces were present to a significantly greater degree than both the autism or schizophrenia groups. While the control and the schizophrenia groups oriented to face regions faster when faces were present compared to when they were absent, the autism group oriented at the same rate in both conditions. The schizophrenia group, meanwhile, exhibited a delay in orienting to face regions across both conditions, although whether anti-psychotic medication contributed to this effect is unclear. These findings suggest that while processing emotional information in social scenes, both individuals with autism and individuals with schizophrenia fixate faces less than controls, although only those with autism fail to orient to faces more rapidly based on the presence of facial information. Autism and schizophrenia may therefore share an abnormality in utilizing facial information for assessing emotional content in social scenes, but differ in the ability to seek out socially relevant cues from complex stimuli. Impairments in social orienting are discussed within the context of evidence suggesting the role of the amygdala in orienting to emotionally meaningful information.     

The relationship of neuropsychological abilities to specific domains of functional capacity in older schizophrenia patients.

BACKGROUND: This study sought to determine the relative importance of cognitive measures in predicting various domains of everyday functional capacity in older outpatients with schizophrenia. METHODS: Ninety-three psychiatry outpatients with diagnoses of schizophrenia and schizoaffective disorders underwent a comprehensive neuropsychiatric evaluation, including neuropsychological testing and clinical ratings of psychopathology. Functional capacity was assessed with the Direct Assessment of Functional Status, a performance measure of basic and instrumental activities of daily living (ADLs/IADLs). RESULTS: Neuropsychological performance significantly predicted most ADLs/IADLs measured, except simple eating behaviors, time orientation, and grooming. Lower educational level and negative symptoms also were associated with worse functional capacity, whereas positive symptoms and depressed mood were not. Measures of cognitive functioning accounted for more variance in functional capacity than did psychiatric ratings of symptoms, and multiple regression analyses demonstrated that neuropsychological performance was predictive of functional capacity, over and above clinical symptoms. No specific cognitive domains were differentially predictive of specific domains of functional capacity. CONCLUSIONS: Neurocognitive abilities were more predictive of functional capacity than level of clinical symptoms; however, these abilities were not specific predictors of functioning. This is consistent with findings of relatively generalized, intercorrelated cognitive impairment in schizophrenia and multiply determined domains of everyday functioning.     

Premorbid performance IQ deficit in schizophrenia

OBJECTIVE: Performance IQ (PIQ) is often lower than verbal IQ (VIQ) in schizophrenic patients. Whether PIQ < VIQ precedes psychotic symptoms in schizophrenia remains uncertain. METHOD: We investigated premorbid IQ scores in 63 subjects assessed at a child and adolescent psychiatric unit (mean age 13.1 years, SD 3.2), who at follow-up in adulthood (mean age 30.9 years, SD 3.9) received a lifetime RDC diagnosis of schizophrenia-related psychosis, affective disorder, or no psychiatric disorder. RESULTS: Premorbid PIQ < VIQ significantly differentiated the groups with schizophrenia-related psychosis and no psychiatric disorder. Subjects with schizophrenia-related psychosis had a significantly lower mean value for premorbid PIQ, but not VIQ, compared to subjects who developed affective disorder or subjects without psychiatric disorder. CONCLUSION: Our results emphasize premorbid intellectual deficits in schizophrenia. Those deficits might largely be in consequence of an impairment on the PIQ scale.     

Negative symptom resolution and improvements in specific cognitive deficits after acute treatment in first-episode schizophrenia.

Patients with first-episode schizophrenia show significant cognitive impairments even at this early phase of their illness. Antipsychotic medication improves clinical symptomatology, but the effectiveness of this treatment on neuropsychological deficits remains unclear. We investigated clinical symptom and neuropsychological performance change in 34 unmedicated first-episode psychotic patients (17 males, 17 females) from the time prior to treatment until 33.6+/-11.3 days after treatment initiation at which time patients demonstrated meaningful recovery from psychosis. Twenty-four matched healthy subjects were also studied. Performance in most neuropsychological functions (language skills, attention, nonverbal learning and reasoning, motor speed) remained stable for the group as a whole. However, reduction in negative symptoms was significantly correlated with performance increases in verbal fluency and attention. Higher negative symptom recovery was associated with improvement of cognitive performance to levels approaching those of healthy subjects, whereas low or no negative symptom improvement was associated with stable or decreased cognitive performance. Reduction in positive symptoms was not associated with change in cognitive abilities. These findings suggest a linkage between early, treatment-induced improvements in negative symptoms and reductions in distinct cognitive deficits.     

The auditory P300 correlates with specific cognitive deficits in Parkinson's disease

Summary An abnormally prolonged latency of the P300 event-related potential has been reported in several types of dementing illnesses, including Parkinson's disease (PD). While some PD patients have dementia, a significant number of PD patients have less severe cognitive impairments. We examined the relationship between the auditory P300 and a neuropsychological battery of 11 tasks in 43 PD patients. The quantitative relationship between the individual neuropsychological measures and the P300 was examined using partial correlation and analysis of covariance techniques which controlled for age, education, and illness duration. The strongest correlations were between P300 and both shortterm memory and visual perception. Global cognitive deficits do not appear to relate to the abnormal P300 responses in PD: instead, specific aspects of cognitive decline accounted for the electrophysiological abnormalities. An abnormally long or absent P300 correlated with deficits on select cognitive tasks: those involving memory, visual perception, and abstract reasoning. The interactions between anatomical and neurochemical abnormalities in PD are discussed in light of the pattern of deficits seen in this study.     

Cognitive deficits in recent-onset and chronic schizophrenia

Although cognitive dysfunction is a primary characteristic of schizophrenia, only recently have investigations begun to pinpoint when the dysfunction develops in the individual afflicted by the disorder. Research to date provides evidence for significant cognitive impairments prior to disorder onset. Less is known about the course of cognitive dysfunction from onset to the chronic phase of schizophrenia. Although longitudinal studies are optimal for assessing stability of cognitive deficits, practice effects often confound assessments, and large and representative subject samples have not been followed over long periods of time. We report results of a cross-sectional study of cognitive deficits early and late in the course of schizophrenia carried out at four different geographic locations to increase sample size and generalizability of findings. We examined a broad set of cognitive functions in 41 recent-onset schizophrenia patients and 106 chronic schizophrenia patients. The study included separate groups of 43 matched controls for the recent-onset sample and 105 matched controls for the chronic schizophrenia sample in order to evaluate the effects of cohort (i.e., age) and diagnosis (i.e., schizophrenia) on cognitive functions. All measures of cognitive function showed effects of diagnosis; however, select time-based measures of problem solving and fine motor dexterity exhibited interactions of diagnosis and cohort indicating that these deficits may progress beyond what is expected with normal aging. Also, worse recall of material in episodic memory was associated with greater length of illness. Nevertheless, findings indicate that nearly all cognitive deficits are comparably impaired across recent-onset and chronic schizophrenia.     

Cognitive deficits and functional outcome in schizophrenia

Cognitive dysfunction is a core feature of schizophrenia. Deficits are moderate to severe across several domains, including attention, working memory, verbal learning and memory, and executive functions. These deficits pre-date the onset of frank psychosis and are stable throughout the course of the illness in most patients. Over the past decade, the focus on these deficits has increased dramatically with the recognition that they are consistently the best predictor of functional outcomes across outcome domains and patient samples. Recent treatment studies, both pharmacological and behavioral, suggest that cognitive deficits are malleable. Other research calls into question the meaningfulness of cognitive change in schizophrenia. In this article, we review cognitive deficits in schizophrenia and focus on their treatment and relationship to functional outcome.