[CAT’S VISUAL AREA 18 INTERMODULAR INTERACTIONS DEVELOPMENT UNDER DIFFERENT VISUAL ENVIRONMENT].

Primary visual cortex contains a set of modules, and their postnatal development depends on a combination of internal genetic and external (defined by visual environment) factors. In order to examine a development of intermodular interactions in visual cortex of kittens subjected to rhythmic light stimulation (15 Hz and 50 Hz frequencies, groups RLS-15 and RLS-50), we investigate an intermodular signal correlation by mean of optical imaging technique. Data was compared with control kittens and with kittens reared with no visual experience in total darkness (group DARK). A significant reduction of the intermodular correlation coefficient was obtained in the group RLS-15; the correlation coefficient values in the groups RLS-50 and DARK was not affected. Thus 15 Hz rhythmic light stimulation during sensitive periods of development disrupts an efficacy of intermodular neuronal connections.