Neuropsychological dysfunction in parents of schizophrenics.

Neuropsychological measures designed to examine aspects of attention, learning efficiency, and memory were investigated in 14 schizophrenic probands, their 28 parents, and 18 normal individuals. Probands performed at levels significantly below normals on measures of attention and of learning efficiency and performed below their parents on a subset of the same measures. Eight families had one parent with a personal or ancestral pedigree history consistent with schizophrenia; the other parent's personal and ancestral history was negative for schizophrenia. In these families, the probands were significantly different from the negative-history parents, but not the positive-history parents on an aggregate index of attention. Schizophrenics were significantly different from both the positive- and negative-history parents on an aggregate index of learning efficiency. These results extend previous findings of specific neuropsychological dysfunction in attention and learning in schizophrenics to show that some of the deficits are present in a subgroup of their parents, those who are likely carriers of genes conveying risk for schizophrenia. The data suggest that a heritable component of the neuropsychological deficit is a primary dysfunction in attention, and that a secondary or additional deficit in learning may be evident in family members who actually express the disorder of schizophrenia.