Neural basis of the association between depressive symptoms and memory deficits in nondemented subjects: Resting-state fMRI study

School of Clinical Medicine, Southeast University, Nanjing, China.
Human Brain Mapping (Impact Factor: 5.97). 06/2012; 33(6):1352-63. DOI: 10.1002/hbm.21291
Source: PubMed

ABSTRACT Depressive symptoms often coexist with memory deficits in older adults and also are associated with incident cognitive decline in the elderly. However, little is known about the neural correlates of the association between depressive symptoms and memory deficits in nondemented elderly. Fifteen amnestic mild cognitive impairment (aMCI) and 20 cognitively normal (CN) subjects completed resting-state functional magnetic resonance imaging (R-fMRI) scans. Multiple linear regression analysis was performed to test the main effects of the Geriatric Depression Scale (GDS) and Rey Auditory Verbal Learning Test delayed recall (RAVLT-DR) scores, and their interaction on the intrinsic amygdala functional connectivity (AFC) network activity. Severer depressive symptoms and memory deficits were found in the aMCI group than in the CN group. Partial correlation analysis identified that the RAVLT-DR scores were significantly correlated with the AFC network in the bilateral dorsolateral prefrontal cortex (DLPFC), dorsomedial and anterior prefrontal cortex, posterior cingulate cortex (PCC), middle occipital gyrus, right inferior parietal cortex, and left middle temporal gyrus (MTG). The GDS scores were positively correlated with the AFC network in the bilateral PCC and MTG, and left DLPFC. The interactive effects of the GDS and RAVLT-DR scores on the AFC network were seen in the bilateral PCC, MTG, and left DLPFC. These findings not only supported that there were interactive neural links between depressive symptoms and memory functions in nondemented elderly at the system level, but also demonstrated that R-fMRI has advantages in investigating the interactive nature of different neural networks involved in complex functions, such as emotion and cognition.

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Available from: Piero Antuono, Sep 29, 2015
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    • "The functional connectivity patterns of the subdivisions of the amygdala should be evaluated in the future. The gray matter volume has been found to be atrophied (Basso et al., 2006; Poulin et al., 2011; Whitwell et al., 2007), and the connectivity patterns have been found to be disrupted (Xie et al., 2012; Yao et al., 2013), in the amygdala of AD/MCI subjects. These impairments of the amygdala may be biomarkers for the diagnosis of MCI. "
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    • "Recent studies have linked the different categories of neurodegenerative diseases to dysfunctions in the distinct and specific brain functional networks (Seeley et al., 2009). A number of studies also have shown that cognitive changes in patients with neurodegenerative diseases are more likely the result of changes in the functional neural networks containing multiple brain regions rather than isolated regions (Kozel et al., 2011; Xie et al., 2011). Hence, cognitive improvement following donepezil treatment suggests that the drug targets and affects functional systems or networks involving multiple brain regions. "
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