Total neuroelectric brain activity derived from resting-state MEG is invariable across the adult lifespan

Ageing of the human brain was studied using large array of experimental data. The magnetic encephalograms and magnetic resonance images of the head were obtained from the open archive CamCAN. Bad data were rejected, then functional tomograms were found - the spatial distribution of elementary spectral components. Physiological noise was eliminated by joint analysis of the functional tomograms and magnetic resonance images. By massively solving the inverse problem, multichannel spectra were transformed into time series of the power of elementary current dipoles. Age-related changes in the electrical power of various brain rhythms were examined. It was found that the summary electrical activity of the brain is constant throughout a person’s life. The electric power is redistributed during the lifetime: delta rhythm is diminishing, giving slow rise to all other rhythms.