Objective-This study evaluated the effects of cognitive remediation for improving cognitive performance, symptoms, and psychosocial functioning in schizophrenia.Method-A meta-analysis was conducted of 26 randomized, controlled trials of cognitive remediation in schizophrenia including 1,151 patients.Results-Cognitive remediation was associated with significant improvements across all three outcomes, with a medium effect size for cognitive performance (0.41), a slightly lower effect size for psychosocial functioning (0.36), and a small effect size for symptoms (0.28). The effects of cognitive remediation on psychosocial functioning were significantly stronger in studies that provided adjunctive psychiatric rehabilitation than in those that provided cognitive remediation alone.Conclusions-Cognitive remediation produces moderate improvements in cognitive performance and, when combined with psychiatric rehabilitation, also improves functional outcomes.Cognitive impairment is a core feature of schizophrenia, with converging evidence showing that it is strongly related to functioning in areas such as work, social relationships, and independent living (1, 2). Furthermore, cognitive functioning is a robust predictor of response to psychiatric rehabilitation (i.e., systematic efforts to improve the psychosocial functioning of persons with severe mental illness) (3), including outcomes such as work, social skills, and self-care (1,4,5). Because of the importance of cognitive impairment in schizophrenia, it has been identified as an appropriate target for interventions (6).Currently available pharmacological treatments have limited effects on cognition in schizophrenia (7,8) and even less impact on community functioning (9). To address the problem of cognitive impairment in schizophrenia, a range of cognitive remediation programs has been developed and evaluated over the past 40 years. These programs employ a variety of methods, such as drill and practice exercises, teaching strategies to improve cognitive functioning, compensatory strategies to reduce the effects of persistent cognitive impairments, and group discussions. Several reviews of research on cognitive rehabilitation in schizophrenia have been published (10-13). The general conclusions from these reviews have been that cognitive remediation NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript leads to modest improvements in performance on neuropsychological tests but has no impact on functional outcomes. However, these reviews were limited by the relatively small number of studies that actually measured psychosocial functioning, precluding any definitive conclusions about the effects of cognitive remediation on psychosocial adjustment or the identification of program characteristics that may contribute to such effects. The rationale for cognitive remediation is chiefly predicated on its presumed effects on psychosocial functioning and improved response to rehabilitation. Therefore, a critical examination of the effects of cognitive ...

Despite the limitations of existing studies, including lack of standardization or psychometric validation of measures, the evidence for deficits across multiple social cognitive domains in schizophrenia is clear. Future research should examine the role of neurobiological and psychosocial factors in models linking various aspects of deficit in schizophrenia, including social cognition, in order to identify targets for intervention.

CT evidenced promise in the treatment of AD, with primarily medium effect sizes for learning, memory, executive functioning, activities of daily living, general cognitive problems, depression, and self-rated general functioning. Restorative strategies demonstrated the greatest overall effect on functioning. Several limitations of the published literature are discussed.

No abstract

Alzheimer's disease (AD) is a common, devastating form of dementia. With the advent of promising symptomatic treatment, the importance of recognizing AD at its very earliest stages has increased. We review the extant neuropsychological and neuroimaging literature on preclinical AD, focusing on longitudinal studies of initially nondemented individuals and cross-sectional investigations comparing at-risk with normal individuals. We systematically reviewed 91 studies of neuropsychological functioning, structural neuroimaging, or functional neuroimaging in preclinical AD. The neuropsychological studies indicated that preclinical AD might be characterized by subtle deficits in a broad range of neuropsychological domains, particularly in attention, learning and memory, executive functioning, processing speed, and language. Recent findings from neuroimaging research suggest that volume loss and cerebral blood flow or metabolic changes, particularly in the temporal lobe, may be detected before the onset of dementia. There exist several markers of a preclinical period of AD, in which specific cognitive and biochemical changes precede the clinical manifestations. The preclinical indicators of AD reflect early compromise of generalized brain integrity and temporal lobe functioning in particular.

With new treatments targeting features of schizophrenia associated with functional disability, there is a need to evaluate the validity of ratings of everyday outcomes. It is unknown whether patients can validly self-report on aspects of their functional status, which would be a potentially economical method for obtaining outcome data. In this study, 67 older schizophrenia outpatients provided self-ratings of everyday real-world functioning using the specific levels of functioning scale (SLOF). They were also administered assessments of neuropsychological performance, performance-based measures of functional capacity and social skills, clinical symptoms, and quality of life. Case managers, unaware of other ratings, also generated SLOF ratings. Based on discrepancy scores, participants were categorized as accurate raters (n = 24), underestimators (n = 16), or overestimators (n = 27) of their functional status as compared to case managers' ratings. Patients' self-rated functional status was correlated with their subjective quality of life, but remarkably unassociated with case manager ratings of functional status or their own performance on functional capacity or social skills measures. Case manager ratings, however, were highly correlated with performance on functional capacity and social skills measures. Patients who underestimated their real world performance had better cognitive skills and greater self-rated depression than those who overestimated. Accurate raters demonstrated greater social skills than both overestimators and underestimators, while overestimators were most cognitively and functionally impaired. Accurate ratings of everyday outcomes in schizophrenia may require systematic observation of real world outcomes or performance-based measures, as self-reports were inconsistent with objective information.

Empirically supported treatments for schizophrenia now include a variety of psychosocial interventions, such as social skills training, vocational rehabilitation, and psychotherapy. As awareness of the functional importance of neurocognitive impairments in schizophrenia has increased, interest in treatments to improve cognition has grown. We review the literature on cognitive training (CT), which has been studied in 17 published randomized, controlled trials to date. The differential effectiveness of noncomputerized and computer-assisted interventions, with and without strategy coaching, and an environmental adaptation intervention, is examined. We conclude that the different types of approaches, whether computer assisted or not, all have effective components that hold promise for improving cognitive performance, symptoms, and everyday functioning. Our recommendations for further research, including the use of functional outcome measures and long-term followup, highlight the importance of improving ecological validity in this area of treatment research.

Objective-Quality of life (QOL) is considered an important outcome in the treatment of schizophrenia, but the determinants of QOL are poorly understood in this population. Furthermore, previous studies have relied on combined measures of subjective QOL (usually defined as life satisfaction) and objective QOL (usually defined as participation in activities and relationships). We examined separately the clinical, functional, and cognitive predictors of subjective and objective QOL in outpatients with schizophrenia. We hypothesized that better subjective QOL would be associated with less severe negative and depressive symptoms, better objective QOL, and greater everyday functioning capacity, and that better objective QOL would be associated with less severe negative and depressive symptoms, better cognitive performance, and greater functional capacity.Method-Participants included 88 outpatients with schizophrenia or schizoaffective disorder who completed a comprehensive series of assessments, including measures of positive, negative, and depressive symptoms; performance-based functional skills; a neuropsychological battery; and an interview measure of subjective and objective QOL.Results-In the context of multiple predictor variables, more severe depressive symptoms and better neuropsychological functioning were independent predictors of worse subjective QOL. More severe negative symptoms predicted worse objective QOL. Functional capacity variables were not associated with subjective or objective QOL.Conclusion-Treatments to improve QOL in schizophrenia should focus on negative symptoms and depressive symptoms.