Chapter 4 - Cognitive impairment and symptom dimensions in psychosis

Summary

This chapter presents the relationship between symptom dimensions and neuropsychological functioning in psychosis. It presents short overview on neuropsychological functioning in schizophrenia and in other psychotic disorders. The chapter describes the studies investigating the association between symptom dimensions and neuropsychological functioning in both schizophrenia and other psychoses. The schizophrenia patients show deficits on a wide range of cognitive domains including verbal memory, working memory, executive functions, attention, and processing speed on a background of general intellectual impairment. Studies that examined differences in cognitive functioning between schizophrenia and affective psychoses reported an increasing gradient of severity of cognitive impairment, from less severe deficits in bipolar disorder to most severe deficits in schizophrenia-like disorders. Validity of symptom dimensions as neurobiological constructs has been supported by several genetic and neurobiological studies. Research on symptom dimensions in psychosis focuses predominantly on schizophrenia.