Peculiarities of EEG Activity under Conditions of Rhythmic Phono- and Photostimulation and Contents of Lead, Strontium, and Calcium in Children Living in Environmentally Disadvantaged Areas of Ukraine.

We examined 12- to 13-year-old children, inhabitants of industrial regions of Ukraine with high levels of environmental contamination; these children suffered from autonomic disorders. Conventional norms for the contents of lead and calcium were exceeded in samples of biologically stable tissues (hairs) of these children; strontium concentrations corresponded to reference values. The analysis of correlations of the absolute and relative spectral powers of EEG frequency components under conditions of rhythmic photoand phonostimulation with the contents of the above elements showed that there were both similarities and specificities of neurotropic effects of these elements at the systemic level. With higher lead concentrations, we observed lower, in general, values of the integral power of EEG activity, while the balance of excitatory and inhibitory neural processes was preserved. The patterns of effects of calcium and strontium were more similar to each other but were dissimilar in the levels of expression. The described effects were, to a great extent, found in EEG samples recorded under conditions of rhythmic photostimulation. We conclude that lead and calcium demonstrated relatively higher neurotropic activities within the examined group. [ABSTRACT FROM AUTHOR]