Concurrent Structural and Functional Patterns in Patients With Amnestic Mild Cognitive Impairment

Abstract

Amnestic mild cognitive impairment (aMCI) is a clinical subtype of MCI, which is known to have a high risk of developing Alzheimer’s disease (AD). Although neuroimaging studies have reported brain abnormalities in patients with aMCI, concurrent structural and functional patterns in patients with aMCI were still unclear. In this study, we combined voxel-based morphometry (VBM), amplitude of low-frequency fluctuations (ALFFs), regional homogeneity (Reho), and resting-state functional connectivity (RSFC) approaches to explore concurrent structural and functional alterations in patients with aMCI. We found that, compared with healthy controls (HCs), both ALFF and Reho were decreased in the right superior frontal gyrus (SFG_R) and right middle frontal gyrus (MFG_R) of patients with aMCI, and both gray matter volume (GMV) and Reho were decreased in the left inferior frontal gyrus (IFG_L) of patients with aMCI. Furthermore, we took these overlapping clusters from VBM, ALFF, and Reho analyses as seed regions to analyze RSFC. We found that, compared with HCs, patients with aMCI had decreased RSFC between SFG_R and the right temporal lobe (subgyral) (TL_R), the MFG_R seed and left superior temporal gyrus (STG_L), left inferior parietal lobule (IPL_L), and right anterior cingulate cortex (ACC_R), the IFG_L seed and left precentral gyrus (PRG_L), left cingulate gyrus (CG_L), and IPL_L. These findings highlighted shared imaging features in structural and functional magnetic resonance imaging (MRI), suggesting that SFG_R, MFG_R, and IFG_L may play a major role in the pathophysiology of aMCI, which might be useful to better understand the underlying neural mechanisms of aMCI and AD.

Reduced functional connectivity induced by longitudinal alterations of structure and perfusion may be associated with cognitive impairment in patients on maintenance hemodialysis

“…Moreover, it plays an essential role in cognitive functions, including working memory, attention, and decision-making (Carlén, 2017). In particular, there is a strong correlation between the SFGmed and the cognitive function (Li et al, 2013;Liu et al, 2022). According to our study, the decrease in GMV in the PFC is in line with that observed in previous studies, indicating that HD may exacerbate deficits in executive function of patients with ESRD.…”

Elevated serum platelet count inhibits the effects of brain functional changes on cognitive function in patients with mild cognitive impairment: A resting-state functional magnetic resonance imaging study

“…Previous studies support our findings. For example, compared with HCs, the ALFF was decreased in the right superior frontal gyrus and right middle frontal gyrus of patients with amnestic mild cognitive impairment (aMCI) ( Liu et al, 2022 ). Another study found that patients with aMCI had decreased ALFF values in the posterior cingulate/precuneus, medial prefrontal cortex, hippocampus/ parahippocampal gyrus, basal ganglia, and prefrontal regions, while ALFF values in several regions of the occipital and temporal lobe were higher compared with the NC group ( Han et al, 2011 ).…”

Functional MRI-specific alterations in frontoparietal network in mild cognitive impairment: an ALE meta-analysis

“…Thus, it presented unabiding and region-specific cholinergic neuroplastic reactions (Ikonomovic et al, 2007 ). Therefore, the SFG could be the major region consisting of various cognitive deficits in MCI, in structural and functional aspects (Liu et al, 2022 ). Besides, attenuated spontaneous neuronal activities of the SFG.R could identify MCI patients from HCs.…”