Recognition of Visual Images: Functional Aspects, Localization, a Clinical Picture

Shelepin Yu.*, Trufanov G.**, Harauzov À.*, Fokin V.**, Krasilnikov N.***, Deshkovich À.**, Rudoy I.**, Pronin S.*

* Pavlov Institute of Physiology of the Russian Academy of Sciences, Saint-Petersburg, Russia;
** Medicomilitary Academy, Saint Petersburg, Russia;
*** University of Aerospace Instrument-making Industry, Saint-Petersburg, Russia


Localization of mechanisms, responsible for perception, processing and realization of sensory information in a human cerebral cortex, was ascertained with the help of electrophysiologic, psychophysiologic methods and functional MRI. We elaborated methods for studying activity of a visual system both as “a device”, working with images, and “an apparatus”, recognizing signs, sign systems and symbols. The first approach was based on iconical methods and the second one - on semiotics and the statistical decision theory. They ensured solving various clinical problems. Besides, these approaches made it possible to explain different diagnostic methods, which had been developed during the last 150 years for study of symptoms and syndromes, characterized either by absence of any ascertained relationship between each other or connected only as clinical entities without understanding physiologic mechanisms. A conception of coordinated filtration within a visual system and formation of a recognizable object pattern was developed on the basis of the statistical decision theory. The most important neurophysiologic mechanisms, providing recognition of visual images, were modeled. We developed a method of measuring a functional state of the brain, based on estimation of internal noise of a visual system. The study demonstrated its convenience for assessing success of treatment in a neurosurgical clinic.