Resting State Network Abnormalities in Alzheimers Disease: Beyond the Default Mode Network

Federica Agosta¹, Michela Pievani^1,2, Cristina Geroldi², Giovanni B. Frisoni², Massimo Filippi¹

Using resting-state (RS) fMRI, the coactivation patterns of the default mode network (DMN) and frontal networks were explored in Alzheimers disease (AD) and amnestic mild cognitive impairment (aMCI) patients. AD was associated with opposing coactivation effects in the DMN (decreased) and frontal networks (enhanced). The only RS abnormality in aMCI patients was a precuneus coactivation reduction in the DMN. The limited resources of the parieto-temporal cortex of AD patients may be paralleled, in an attempt to maintain cognitive efficiency, by an increased prefrontal coactivation. A medial parietal RS fMRI change seems to be present since the early phase of AD.