The Search for the Psychobiological Substrate of Childhood Onset Schizophrenia

This paper describes a program of neurobehavioral research aimed at: (1) isolating core information processing impairments in childhood onset schizophrenia, and (2) identifying structures in the central nervous system which mediate those impairments. Children meeting DSM-III criteria for schizophrenia, mental age matched normals, and younger normals were administered a series of visual information processing tasks. The results of these studies suggest that controlled attentional processes, which normally develop during middle childhood, are impaired in schizophrenic children while more automatic modes of attending are relatively intact. Convergent evidence for this conclusion was provided by event related potentials recorded from 7 scalp loci while children were performing on one of the tasks used in the first project. The schizophrenic children produced a small contingent negative variation (CNV) which was slow to develop and resolve as well as diminished amplitudes for N1, P3, and slow wave components. This suggests that these children are impaired in their ability to regulate the mobilization and direction of attention and to discriminate target stimuli. Event-related potential components of the schizophrenic children tended to be most deviant at frontal leads, but midline and lateralized deficits were also seen at vertex and posterior recording sites. The relationship of these impairments in controlled attentional processes to the phenomenology of childhood onset schizophrenia is discussed.