Translating basic attentional paradigms to schizophrenia research: reconsidering the nature of the deficits.

Abnormalities in attention have long been viewed as one of the fundamental underlying cognitive deficits in schizophrenia, likely contributing both to formation of some types of symptoms and particularly to the substantial work and social impairments that often accompany schizophrenia. Yet, the precise nature of the attentional deficits in schizophrenia remains poorly understood. Translating advances in cognitive psychology to clinical research brings paradigms with greater analytic power to the study of attention in schizophrenia. In particular, these paradigms should shed light on whether the attentional dysfunction in schizophrenia is best conceptualized as arising from limitations in amount or allocation of processing capacity or from more specific structural bottlenecks that do not allow certain processes to be carried out in two tasks simultaneously. Certain types of dual-task paradigms are particularly well suited to make distinctive predictions, particularly those involving a psychological refractory period paradigm. The background and design of a series of ongoing studies of prodromal, first-episode, and chronic schizophrenia patients are described that are addressing the developmental course of attentional dysfunction in this disorder. These refined paradigms should substantially increase our understanding of the specific forms of attentional impairment characterizing schizophrenia and their connections to symptom development and functional outcome.