Neurodevelopmental theory of pathogenesis of schizophrenia assumes that the development of this condition depends on factors acting long before first clinical symptoms appear. These factors result in disturbed process of neuronal development, particularly within the frontal lobes and prefrontal cortex, temporal lobes, thalamus and several components of the limbic system. These structural abnormalities may be the underlying substrate of cognitive deficits seen in patients with schizophrenia and their relatives, which recently have focused much interest in psychiatric literature. Neuropsychological assessment thereof is increasingly used in the diagnostic-therapeutic management of these patients. Cognitive processes and their disturbances have become a topic of interest of scientific community in our country, but lack of diagnostic tools developed and verified for and in Polish specific conditions creates certain methodological difficulties associated with accurate and objective measurement of cognitive functions. This paper presents particular cognitive functions, whose deficit may occur in patients with schizophrenia. These relate mainly to attention, memory, executive function, psychomotor speed, visual-spatial coordination and fluency of thinking. Next, discussed are psychological tests serving to evaluate particular cognitive functions, with an emphasis on their Polish standardization, normalization and availability of parallel versions. Subsequently, methodological aspects of cognitive function testing are presented. Discussed are several aspects of cultural adaptation of tests, their reliability and accuracy. Methodology of repeated measurements, accounting for the so-called "practice effect" is described. Finally, presented are the results of factor-related analyses of selected psychological tests, as well as their impact on the results obtained.
