Changes in the spatial synchronization of the cortical electrical activity under extreme (hyperbaric) conditions.

Spectral correlation methods of EED-analysis were used to study the local synchronization (by power spectra--FFT) and the spatial synchronization (by assessing the coherence functions) of the cortical electrical activity of persons subjected to prolonged (one-month) extreme impact--hyperbaric conditions. Two neurophysiological mechanisms of system functional organization of the electrical activity of the central nervous system are described, through which the brain compensates its reduced functional capacities under the extreme conditions studied (including boundary physiological states). These mechanisms: (a) act in almost all situations of the extreme impact, irrespective of the scope of the remaining varied transient or lasting readjustments in the EEG, and (b) guarantee spatial interactions in the electrical activity in the brain in frequency ranges which are essential for its functions: alpha (8-12 Hz) and beta-2 (24-36 Hz).