doiSerbia

Topography and asymmetry of visual EEG reactivity in healthy school-age children

Ristanović Dušan S. (Institut za biofiziku Medicinskog fakulteta, Beograd)
Martinović Žarko J. (Odsek za epilepsije i kliničku neurofiziologiju Instituta za mentalno zdravlje, Beograd)
Jovanović-Čupić Vesna (Zavod za bolesti zavisnosti, Beograd)

In order to quantify the visual reactivity of EEC to opening the eyes, the topography of EEG power spectra in a sample of 72 healthy subjects aged from 7-15 years, was studied. The EEGs were recorder at 14 scalp sites under eyes closed (ECL) and eyes open (EOP). It has been established that the absolute powers in total and in alpha band were significant- ly higher in all derivations under ECL as compared with EOP condition. Except for the frontal derivations, absolute power in theta band under ECL condition was significantly higher than that under EOP condition. Changes in delta and beta powers were seldom significant. In beta 2 band no EEG blocking was noticed in anterior area. Opening the eyes significantly influenced the values of asymmetry index in alpha band and total power. In all frequency bands and under both conditions, the differences of powers between the hemi spheres were found mainly in the prefrontal and laterofrontal areas. The results showed that the visual blocking of EEG was mostly due to a higher degree of EEG desynchronization after opening the eyes.

Keywords: Visual reactivity, brain topography, spectral analysis, EEG asymmetry, healthy children