Skip to Main content Skip to Navigation
Journal articles

Changes in Hippocampal Connectivity in the Early Stages of Alzheimer's Disease: Evidence from Resting State fMRI

Abstract : A selective distribution of Alzheimer's disease (AD) pathological lesions in specific cortical layers isolates the hippocampus from the rest of the brain. However, functional connectivity between the hippocampus and other brain regions remains unclear in AD. Here, we employ a resting state functional MRI (fMRI) to examine changes in hippocampal connectivity comparing 13 patients with mild AD versus 13 healthy age-matched controls. Hippocampal connectivity was investigated by examination of the correlation between low frequency fMRI signal fluctuations in the hippocampus and those in all other brain regions. We found that functional connectivity between the right hippocampus and a set of regions was disrupted in AD; these regions are: medial prefrontal cortex (MPFC), ventral anterior cingulate cortex (vACC), right inferotemporal cortex, right cuneus extending into precuneus, left cuneus, right superior and middle temporal gyrus and posterior cingulate cortex (PCC). We also found increased functional connectivity between the left hippocampus and the right lateral prefrontal cortex in AD. In addition, rightward asymmetry of hippocampal connectivity observed in elderly controls was diminished in AD patients. The disrupted hippocampal connectivity to the MPFC, vACC and PCC provides further support for decreased activity in “default mode network” previously shown in AD. The decreased connectivity between the hippocampus and the visual cortices might indicate reduced integrity of hippocampus-related cortical networks in AD. Moreover, these findings suggest that resting-state fMRI might be an appropriate approach for studying pathophysiological changes in early AD.
Document type :
Journal articles
Complete list of metadata
Contributor : Chine Publications Liama Connect in order to contact the contributor
Submitted on : Wednesday, January 10, 2007 - 2:30:08 PM
Last modification on : Saturday, October 9, 2021 - 4:07:24 AM

Links full text




Liang Wang, Yufeng Zang, Yong He, Meng Liang, Xinqing Zhang, et al.. Changes in Hippocampal Connectivity in the Early Stages of Alzheimer's Disease: Evidence from Resting State fMRI. NeuroImage, Elsevier, 2006, NeuroImage, 31 (2), pp.496-504. ⟨10.1016/j.neuroimage.2005.12.033⟩. ⟨inria-00123587⟩



Record views