Neurophysiologic mechanisms of attention: A selective review of early information processing in schizophrenics

Attention is an integral component of information processing. A pronounced attention deficit exists among people with schizophrenia and their first-de gree relatives as compared to persons without this pathology. Schizophrenic s demonstrate marked deficiencies on psychophysical tasks that require temp oral and / or spatial integration, properties that are associated with the two primary visual pathways composed of magnocellular (M) and parvocellular (P) cells, respectively. The deficit expresses itself as a dysfunctional i nformation processing system that affects higher order processes, for examp le, perceptual ability and memory. The focus of this review is to integrate results from several divergent areas of research to include those studies that identify the contributions of the M and P pathways associated with inf ormation processing and the attention deficit. The diverse approaches revie wed in this chapter converge to provide a neurophysiologic explanation of t he attention deficit in schizophrenia.