A study, conducted by researchers from Aix-Marseille University, Forschungszentrum Jülich and Heinrich-Heine University Düsseldorf, utilised virtual brain models to explore the connection between healthy brain ageing and cognitive decline. The study, made possible by the EBRAINS research infrastructure, aimed to understand how structural changes in the brain are linked to variations in cognitive decline among individuals. The study made use of a large dataset from the "1000BRAINS" cohort study, examining over 1,000 participants aged 55-85 through magnetic resonance imaging (MRI). Analysing this extensive dataset, the researchers identified specific structural changes associated with ageing.
Virtual brain models were created to simulate the functional consequences (i.e. the consequences on cognition) of these structural changes. By introducing degradation between the brain's hemispheres in the Virtual Brain Aging model, the researchers replicated the functional changes observed in the ageing process. This included simulating the "functional dedifferentiation" process, whereby the ageing process is associated with a decrease in the division and specialisation of different regions of the brain. The researchers extended their findings to the individual level by generating virtual brains for each participant in the 1000BRAINS study. They confirmed that specific individual structural changes (in particular a process called ‘interhemispheric fibre tract decline’ linked to white matter decline in the brain) predicted varying degrees of functional decline. In summary, the study, enabled by EBRAINS, demonstrated that manipulating brain structure in through computer-derived models replicated observed trajectories of white matter decline and supported the dedifferentiation hypothesis. These findings provide mechanistic insights into how changes in the architecture of functional brain networks contribute to cognitive decline during ageing.
https://www.sciencedirect.com/science/article/pii/S1053811923005542
