Аннотация:The investigation of visual illusions is very important for visual system modeling. The illusory effect may arise at different levels of data processing: sensory level, cortical and high cognitive level. Every level involves specific mechanisms in the illusion formation. In order to reveal those mechanisms, we can use specific stimulation to provoke required illusory effect. The results of our experiments showed that some illusions (such as Vasarely and Benary illusions) could be explained only by multilevel mechanisms