Different functional connectivity gradients reflect aging and Alzheimer's disease.

Functional connectivity changes linked to aging and Alzheimer's disease are aligned with distinct hierarchical brain communication axes, with AD associated with the sensory-association axis and aging with the representation-executive axis.

• Why it matters: Understanding how large-scale brain communication patterns change with age and disease can clarify mechanisms underlying cognitive decline and aid in developing targeted interventions.
• What they did: The study analyzed functional connectivity in two independent cohorts (BioFINDER-2 with 973 participants and ADNI with 129 participants) to identify how aging and AD relate to different axes of hierarchical brain communication.
• The result: Findings suggest that AD and aging alter orthogonal functional pathways in the brain, positioning whole-brain connectivity dynamics as a framework for interpreting functional changes across the adult lifespan.