Cognitive performance is typically conceptualized in terms of domains of functioning. These domains are hierarchical in nature, with the bottom referring to more basic sensory and perceptual processes and the top referring to elements of executive functioning and cognitive control. Domains are not independent of each other and executive functioning exerts control over the utilization of more basic processes. Assessments are typically targeted at subdomains of each ability area and careful combination of tasks can reveal patterns of performance consistent with a variety of different neurological and neuropsychiatric conditions. This review covers the general structures of domains, the patterns of impairments across domains seen in common neuropsychiatric conditions, and use of assessment strategies to differentiate, to the extent possible, between different types of conditions manifesting cognitive impairment. .
Negative symptoms and cognitive deficits in schizophrenia share many features and are correlated in their severity on a cross-sectional basis. The question arises as to the nature of this relationship: are these symptoms the same, caused by the same factor (or factors); or is the nature of their relationship determined by other factors, such as definitional issues and common correlates? In this article we provide a conceptual overview for addressing this question and provide a selective review of the literature on the cross-sectional and longitudinal relationships between these two features of the illness. We describe 4 different models of the "true" relationship between these variables. Some data suggest that the relationship between these variables is determined by the definition of negative symptoms employed and that, in general, the correlation is moderate at the most. Further, path modeling suggests the possibility, to be addressed with later research, that correlations between negative and cognitive symptoms and everyday functional outcomes may influence the observed correlations between these variables. Thus, we conclude that negative and cognitive symptoms may be separable, if not conceptually independent, domains of the illness and that it might be possible to develop treatments that target negative symptoms and cognitive deficits independently.
Recovery in schizophrenia is receiving increasing attention. Part of the increased focus is based on the recent working criteria for clinical remission in schizophrenia and the realization that many people with schizophrenia meet these criteria for remission. In this article, we consider whether functional disability can also be evaluated in a "remission" model. In so doing, we evaluate the concept of clinical remission, evaluate the possibility of remission of other generally stable features of schizophrenia such as negative symptoms, and make some heuristic terminological recommendations. We also propose a "level and breadth" model for the definition of functional remission and examine some of the alternate influences that could produce suboptimal everyday functioning, including effort, motivation, and societal barriers toward functional achievement.
31 March 2012 in Dialogues in clinical neuroscience
Neuropsychological assessment is a performance-based method to assess cognitive functioning. This method is used to examine the cognitive consequences of brain damage, brain disease, and severe mental illness. There are several specific uses of neuropsychological assessment, including collection of …
Recently, attention to the assessment and treatment of functional disability has increased notably. It is widely understood that impairments in everyday living skills, including independent living skills, social functions, vocational functioning, and self-care, are present in people with schizophrenia. It has also become clear recently that assessment of these skills can pose substantial challenges. These challenges include selection of meaningful short-term outcome measures and avoiding bias and reduced validity in the data. Self-report, direct observation, and informant reports of everyday disability all have certain advantages but appear to be inferior to direct assessment of skills with performance-based measures. This review outlines the issues associated with the assessment of functional skills and everyday functioning and provides a description of the strengths and weaknesses of these approaches. We conclude that direct assessment of functional capacity has substantial advantages over other measures and may actually provide a more direct and valid estimate of functional disability than performance on the more distal neuropsychological assessment measures.