Groups of brain regions that synchronize their activity during memory tasks become smaller and more numerous as people age, according to a study.
Typically, research on brain activity relies on average brain measurements across entire groups of people. In a new study, Elizabeth Davison, and colleagues describe a novel method to characterize and compare the brain dynamics of individual people.
The researchers used functional magnetic resonance imaging (fMRI) to record healthy people's brain activity during memory tasks, attention tasks, and at rest. For each person, fMRI data was recast as a network composed of brain regions and the connections between them. The scientists then use this network to measure how closely different groups of connections changed together over time.
They found that, regardless of whether a person is using memory, directing attention, or resting, the number of synchronous groups of connections within one brain is consistent for that person. However, between people, these numbers vary dramatically.