Frequency-dependent alterations in functional connectivity associated with the progression from aMCI to AD

Motivation: In Alzheimer’s Disease (AD) spectrum disorders, rs-fMRI signals in the cerebral cortex may possess distinct characteristics across different frequency ranges. Goal(s): To investigate potential alterations in functional connectivity among patients with amnestic mild cognitive impairment (aMCI) and AD and to determine whether these changes vary across different frequency bands. Approach: The changes in functional connectivity were analyzed using the VMHC and DC metrics in patients with aMCI and AD across three frequency bands:classic, slow-5, and slow-4. Results: Notable changes in functional connectivity were observed across multiple brain regions in patients with aMCI and AD, with the most pronounced in slow-5 frequency band. Impact: This study further advances our comprehension of the pathological and physiological mechanisms associated with AD. Furthermore, it highlights the significance of researchers taking into account various frequency bands in their investigations of brain function.