[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.

[Effect of propofol on functional response of neuronal population in cat primary visual cortex].

The impact of system anesthetic propofol on strength of functional response was investigated in population of primary visual cortex neurons. Elaborated protocol of anesthesia allowed appropriate depth of anesthesia and artifact free experimental data recording. At the start of experiment optical access to the surface of cortex was provided. Propofol was used as main general anesthetic. Control of anesthesia depth was carried out by monitoring of physiological parameters. Effect ofpropofol on functional response was evaluated by intrinsic optical imaging. Stability of neuronal response was estimated during whole experiment and after single injection ofpropofol. It was shown that extended administration ofpropofol do not have negative influence on strength of recorded neuronal signal. At the same time bolus of propofol depresses amplitude of response. Practical recommendations are suggested for conduction of longitudinal neurophysiological experiments using propofol as main anesthetic.