Disruption of Resting Functional Connectivity in Alzheimer’s Patients and At-Risk Subjects
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The resting brain exhibits continuous intrinsic activity, which is correlated between groups of regions forming resting state networks. Evaluating resting connectivity is a popular approach for studying brain diseases. Several hundred studies are now available that address integrity of resting connectivity in patients with Alzheimer’s disease (AD) and mild cognitive impairment (MCI), as well as preclinical at-risk subjects. Most studies focus on the default mode network, a system of specific brain areas showing strong connected resting activity that attenuates during goal-directed behavior. The extent of intrinsic brain activity tends to be strongly correlated with cognitive processes and is specifically disrupted in AD and MCI patients and at-risk subjects, with changes seeming to evolve during the transition between the disease stages. In this study, we review the current findings in default mode network and other resting state network studies in AD and MCI patients and at-risk subjects as assessed by resting state functional magnetic resonance imaging.
KeywordsFunctional connectivity fMRI Resting state Resting state networks Default mode network Alzheimer’s disease Mild cognitive impairment
This work was supported by the project “CEITEC - Central European Institute of Technology” (CZ.1.05/1.1.00/02.0068) from the European Regional Development Fund and by the Czech Science Foundation grant no. 14-33143S.
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Conflict of Interest
Lenka Krajcovicova and Radek Marecek have received the following grant: project “CEITEC - Central European Institute of Technology” (CZ.1.05/1.1.00/02.0068) from the European Regional Development Fund.
Michal Mikl has received the following grant: project “CEITEC - Central European Institute of Technology” (CZ.1.05/1.1.00/02.0068) from the European Regional Development Fund. Dr. Mikl has also received a research grant of Czech Science Foundation no. 14-33143S (Influence of physiological processes on reliability and temporal fluctuations of human brain connectivity measured by fMRI).
Irena Rektorova has received the following grant: project “CEITEC - Central European Institute of Technology” (CZ.1.05/1.1.00/02.0068) from the European Regional Development Fund. Dr. Rektorova has also received a research grant of Czech Science Foundation no. 14-33143S (Influence of physiological processes on reliability and temporal fluctuations of human brain connectivity measured by fMRI).
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
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