Störungen der Handlungskontrolle im Kontext neuropsychologischer Befunde bei Schizophrenie

Abstract

Based on a review of neurobiological and neuropsychological findings in schizophrenia, we illustrate how experimental neuropsychological research contributes to the understanding of schizophrenia. It is shown that cognitive performance deficits are a central feature of schizophrenia. They are closely connected with changes of brain physiology and appear to reflect disturbances of basic cognitive functions. It is difficult to identify these functions, because task performance usually taps various cognitive processes. However, isolation of functions is possible by experimental variation of tasks that require a small number of well defined processes. To illustrate this, we review several recent studies that experimentally analyzed deficits in the control of fast eye movements (saccades). In the antisaccade task schizophrenia patients show distinct, temporally stable and often replicated performance deficits. The reviewed studies suggest that these deficits predominantly reflect a weakness in the volitional initiation of action.