The article, based on the investigations carried out in 91 school students aged 7–18 years who were exposed to severe weather conditions as residents of the European North of Russia, analyzes the processes underlying the development of structures for providing the spatial synchronization of cerebral bioelectric potentials. The coherence values were evaluated for 19 channels (171 pairs of leads) in five basic EEG frequency bands (Δ, θ, α1, α2, and β). The article describes the age-related dynamics, gender-specific features, and topical specificity in the development of coherent connections in the left and right cerebral hemispheres, as well as in the formation of interhemispheric and interregional connections. We used a computerized evaluation technique for distinguishing between three school age groups of northerners using the frequency structure of EEG coherence with the purpose of elaborating some criteria for diagnosing school students with a developmental delay in the formation of spatial organization for the interaction of local EEG processes. The recorded age-related changes in the EEG-pattern structure reflect the pattern of morphofunctional brain development in children and adolescents exposed to the severe conditions of the North at different stages of their postnatal ontogenesis.