Aging is accompanied by cognitive changes but strong variations across individuals exists. One of the ways to characterize this individual variability is to use techniques such as magnetoencephalography (MEG) to measure the dynamics of synchronization between brain regions and the variability of this connectivity over time. Indeed, few studies have focused on the fluctuations in the dynamics of brain networks over time and their evolution with age. We therefore used this method on the Cam-CAN database. We show here that with age an increase in the variability of brain synchronization, as well as a reversal of the direction of information transfer in the default mode network (DMN), in delta frequency band takes place. These changes in functional connectivity were associated with cognitive decline. These results suggest that advancing age is accompanied by a functional disorganization of dynamic networks with a loss of communication stability and a decrease in the information transmitted. This could be partly due to the loss of integrity of the network structure.

No abstract