Phase ordering in the near-critical regime of the Alzheimer's and normal brain

Criticality is an emergent phenomenon observed during second-order phase transitions. The brain is increasingly seen as a complex system that operates near criticality, where complex systems exhibit high correlations. When approaching criticality, a system shows `domain'-like regions with competing phases and increased spatiotemporal correlations that tend to diverge. The dynamics of these domains depend on the system's proximity to criticality. By mapping fMRI signals from the brain to a spin-lattice model, we can study brain's critical behavior. However, the extent to which the normal and Alzheimer's brain exhibit distinct critical ordering based on their proximity to criticality remains unclear. In this study, we investigate the domain properties of the spin-lattice model derived from the Alzheimer's and cognitively normal subjects.