Brain functions emerge from the coordinated dynamics of many brain regions. Dynamic functional connectivity (dFC) analyses are a key tool to describe such dynamic complexity and have been shown to be good predictors of cognitive performance. This is particularly true in the case of Alzheimer’s disease (AD) in which an impoverished dFC could indicate compromised functional reserve due to the detrimental effects of neurodegeneration.
In this Network Neuroscience paper in collaboration with Viktor Jirsa, Ana Solodkin and Michael Breakspear, we observe that in healthy aging, dFC is indeed spatiotemporally organized, as reflected by highorder correlations between multiple regions. However, in people with aMCI or AD, dFC becomes less “entangled,” more random-like, and intermittently bursty. To find these results we further develop the previous notion of « meta connectivity » (or edge-based Functional connectivity) and identify the loss of efficiency of « meta-hubs » (or controllers of dynamics) –and not of classical hubs– as a characteristic signature of cohorts with degraded cognitive performance.
We speculate that this degraded spatiotemporal coordination may reflect dysfunctional information processing, thus ultimately leading to worsening of cognitive deficits.
To know more:
- Arbabyazd, L., Petkoski, S., Breakspear, M., Solodkin, A., Battaglia, D., and Jirsa, V. (2023). State-switching and high-order spatiotemporal organization of dynamic functional connectivity are disrupted by Alzheimer’s disease. Netw. Neurosci. 7, 1420–1451. 10.1162/netn_a_00332.