Early information processing deficit in schizophrenia. New findings using schizophrenic subgroups and manic control subjects.

In recent years, the idea that schizophrenia involves a primary disturbance of the higher cognitive (ie, cortical) thinking processes has been challenged by investigators who have shown that there may be a primary disturbance in schizophrenia in the early stages of information processing that occurs during the first few hundred milliseconds after the stimulus reaches the sense organs. Among the hypothesized early information processing deficits are deficiencies in iconic storage (a brief peripheral memory store) and slowness of processing from iconic storage to a more permanent memory system. Three experiments were conducted using tachistoscopically presented stimuli in order to evaluate these two stages of information processing (iconic storage and speed of processing) in schizophrenic and control subjects. Results converged in supporting the hypothesis, that independent of iconic storage and sensory registration, slow information processing is a relatively stable deficit of schizophrenic patients with a poor prognosis. The schizophrenic patients with a good prognosis had a similar deficit, which was reversible. Results are discussed as they relate to the early information processing deficit theories of schizophrenia.