The classification process in visual perception

Theoretical approaches to interrelation between knowledge and perception are presented. For a long time cognition was only considered a continuation of sensory-perception processes. This was determined by the history of Wundt's experimental psychology development and Fehner's research of sensory processes as primary stage of cognition. Only in the middle of the 20th century the idea about importance of cognition in the perception process gained popularity. Despite perceptive basis of knowledge emphasized by modern approaches, the authors have to introduce a classification process of sensory information at the earliest stages.