Extreme events in the temporal variability of brain signals, a new biomarker of healthy brain function across the lifespan

Establishing trajectories of how brain activity evolves across the lifespan can not only deepen our understanding of the aging process, but can also serve as an early detection system for when an individual deviates from healthy aging. This research project aims to establish a trajectory of healthy brain function by identifying a brain-based biomarker of healthy aging across the lifespan. The data for this project consists of resting-state magnetoencephalography recordings from a large cohort of healthy adults (n=645), aged 18 to 89, sourced from the Cam-CAN repository. The first part of this thesis found that extreme events in magnetoencephalography signals are a significant characteristic of their temporal variability. The second part tracked these extreme events across age and found age-related shifts in their occurrence across the lifespan. These findings contribute to a deeper comprehension of the brain aging process and establish extreme events as a biomarker of healthy aging. This biomarker can be used to track health across the lifespan and allows for earlier interventions to keep individuals on healthy trajectories.