NEUROPSYCHOLOGICAL RISK INDICATORS FOR SCHIZOPHRENIA - A REVIEW OF FAMILY STUDIES

We reviewed potential neuropsychological risk indicators for schizophr enia by addressing two broad questions about neuropsychological perfor mance in biological relatives of schizophrenia patients: (1) Is there evidence of deficits, and, if so, (2) are those deficits similar to de ficits found in schizophrenia patients themselves? There has not yet b een adequate validation of most neuropsychological risk indicators, bu t promising leads have emerged from studies of relatives of persons wi th schizophrenia. The strongest evidence of impairment in relatives wa s in sustained attention, perceptual-motor speed, and concept formatio n and abstraction; to a slightly lesser extent, mental control/encodin g (primarily with distraction) was implicated as well. Impairments in verbal memory and verbal fluency were also found, although these have been less well studied. The pattern of deficits paralleled that found in schizophrenia patients, thus suggesting dysfunction in prefrontal, temporal-limbic, and attentional systems. Findings were similar for ch ildren and adult relatives of schizophrenia patients. It is suggested that future studies (1) emphasize comprehensive test batteries, (2) de velop composite neuropsychological measures, (3) use profile and devia nt-responder analyses, (4) include psychiatric comparison groups, and (5) integrate neuropsychological assessments with brain imaging techni ques.