Cognitive slippage in children vulnerable to schizophrenia.

Psychological deficit research with adult schizophrenics has been hindered by numerous methodological problems that may be avoided by the prospective study of children vulnerable to the disorder. An object sorting task was administered to 156 children of schizophrenic patients, 102 children of depressed patients, and 139 children of normal parents. The children were between 6 and 15 years old. The children of schizophrenic parents made fewer "superordinate" sorting responses than those of normal parents, and more "complex" sorts (a category of inadequate responses) than children of either normal and depressed parents. Our analyses showed that these deficits could not be explained by differences in intelligence. These deficits in conceptual performance may reflect the genotypic predisposition to schizophrenic and/or represent an early precursor of later maladjustment.