Information processing and attention dysfunctions in schizophrenia

Abnormalities of information processing have played a central role in understanding schizophrenia since the time of Kraepelin and Bleuler. Clearly, schizophrenia spectrum patients have profound problems focusing attention on salient cues and overcoming the disrupting effects of distracting stimuli. Theoretically, such patients are rendered vulnerable to stimulus inundation, cognitive fragmentation, and thought disorder induced by this inability to adequately process self-generated cognitive cues and stimuli from the complex world that surrounds us. Adding to the strength of such theories, investigators have made considerable progress in clarifying the functional significance and neurobiological basis of information-processing/attentional dysfunctions. This article focuses on our understanding of information-processing/attentional dysfunctions in schizophrenia. The relevant material will be presented in four parts: (1) an overview; (2) a review of specific, conceptual issues in information-processing research of the group of schizophrenias, including the roles of antipsychotic medications and generalized versus specific deficits; (3) a review of 10 common techniques used to tap the information processing and attention dysfunctions of schizophrenia patients; recent advances and novel applications of these techniques in "boundary" populations such as high-risk children and schizotypal patients are discussed and psychopharmacological probes, animal models, and basic strategies are also reviewed; and (4) an integration and suggestions for future directions in information-processing/attention research in schizophrenia. Overall, information-processing research provides an important viewpoint from which we can understand the group of schizophrenias.