Enhanced resting-state functional connectivity between core memory-task activation peaks is associated with memory impairment in MCI

• Published in: Neurobiology of aging Vol. 45; pp. 43 - 49
• Main Authors: Zhang, Yifei, Simon-Vermot, Lee, Araque Caballero, Miguel Á., Gesierich, Benno, Taylor, Alexander N.W., Duering, Marco, Dichgans, Martin, Ewers, Michael
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.09.2016
• Subjects: Aged; Aged, 80 and over; Alzheimer Disease - psychology; Alzheimer's disease; Brain - diagnostic imaging; Brain - physiopathology; Cognition - physiology; Cognitive Dysfunction - diagnostic imaging; Cognitive Dysfunction - psychology; Compensation; Episodic memory; Female; Functional connectivity; Functional Neuroimaging; Humans; Internal Medicine; Magnetic Resonance Imaging; Male; Memory - physiology; Memory, Episodic; Mild cognitive impairment; Nerve Net - diagnostic imaging; Nerve Net - physiopathology; Network; Neurology; Predictive Value of Tests; Rest - physiology; Resting-state functional MRI; Functional connectivity; Mild cognitive impairment; Compensation; Network; Resting-state functional MRI; Alzheimer's disease; Episodic memory
• ISSN: 0197-4580; 1558-1497; 1558-1497
• DOI: 10.1016/j.neurobiolaging.2016.04.018

Resting-state functional connectivity (FC) is altered in Alzheimer's disease (AD) but its predictive value for episodic memory impairment is debated. Here, we aimed to assess whether resting-state FC in core brain regions activated during memory-task functional magnetic resonance imaging is altered and predictive of memory performance in AD and amnestic mild cognitive impairment (aMCI). Twenty-three elderly cognitively healthy controls (HC), 76 aMCI subjects, and 19 AD dementia patients were included. We computed resting-state FC between 18 meta-analytically determined peak coordinates of brain activation during successful memory retrieval. Higher FC between the parahippocampus, parietal cortex, and the middle frontal gyrus was observed in both AD and mild cognitive impairment compared to HC (false-discovery rate—corrected p < 0.05). The increase in FC between the parahippocampus and middle frontal gyrus was associated with reduced episodic memory in aMCI, independent of amyloid-beta positron emission tomography binding and apolipoprotein E ε4-carrier status. In conclusion, increased parahippocampal-prefrontal FC is predictive of impaired episodic memory in aMCI and may reflect a dysfunctional change within the episodic memory–related neural network.