title: Cognitive processing efficiency in schizophrenia: generalized vs domain specific deficits.
abstract: The issue of generalized vs specific cognitive deficits in schizophrenia was explored by examining reaction time data from 40 published studies with 196 reaction time conditions. Using a regression-based approach, the proportional relationship between the response times of groups with schizophrenia was compared with those of age-matched, healthy comparison groups. Through this method, the extent to which deficits in processing efficiency are explained by a single factor, general processing speed, was compared with possible domain specific or task specific deficits. The results suggest that, overall, the data conforms well to a general linear slowing model which accounts for 87% of the variance in reaction time performance. Some additional variance, however, is accounted for by different degrees of linear slowing for three types of tasks: tasks involving selective attention/inhibition showed the most slowing (2.3-times slower for schizophrenia), followed by lexical tasks (1.8-times slower for schizophrenia), and finally, non-lexical tasks showed the least slowing (1.4-times slower for schizophrenia). This pattern is distinct from other groups showing generalized slowing, such as older adults, and suggests a unique pattern of information processing deficits in schizophrenia.
authors.affiliation: Department of Psychology, Washington University of St. Louis, Missouri, USA. jschatz@itsa.ucsf.edu
authors.forename: J
authors.initials: J
authors.lastname: Schatz
mesh_terms: D000328:Adult; D003072:Cognition Disorders / Q000175:diagnosis / Q000209:etiology*; D006801:Humans; D011930:Reaction Time; D012559:Schizophrenia / Q000150:complications*