Functional brain activity in patients with amnestic mild cognitive impairment: an rs-fMRI study

Abstract

BackgroundAmnestic mild cognitive impairment (aMCI) is an early stage of Alzheimer’s disease (AD). Regional homogeneity (ReHo) and amplitude of low-frequency fluctuation (ALFF) are employed to explore spontaneous brain function in patients with aMCI. This study applied ALFF and ReHo indicators to analyze the neural mechanism of aMCI by resting-state functional magnetic resonance imaging (rs-fMRI).MethodsTwenty-six patients with aMCI were included and assigned to the aMCI group. The other 26 healthy subjects were included as a healthy control (HC) group. Rs-fMRI was performed for all participants in both groups. Between-group comparisons of demographic data and neuropsychological scores were analyzed using SPSS 25.0. Functional imaging data were analyzed using DPARSF and SPM12 software based on MATLAB 2017a. Gender, age, and years of education were used as covariates to obtain ALFF and ReHo indices.ResultsCompared with HC group, ALFF decreased in the left fusiform gyrus, left superior temporal gyrus, and increased in the left cerebellum 8, left inferior temporal gyrus, left superior frontal gyrus (BA11), and right inferior temporal gyrus (BA20) in the aMCI group (p < 0.05, FWE correction). In addition, ReHo decreased in the right middle temporal gyrus and right anterior cuneiform lobe, while it increased in the left middle temporal gyrus, left inferior temporal gyrus, cerebellar vermis, right parahippocampal gyrus, left caudate nucleus, right thalamus, and left superior frontal gyrus (BA6) (p < 0.05, FWE correction). In the aMCI group, the ALFF of the left superior frontal gyrus was negatively correlated with Montreal Cognitive Assessment (MoCA) score (r = −0.437, p = 0.026), and the ALFF of the left superior temporal gyrus was positively correlated with the MoCA score (r = 0.550, p = 0.004). The ReHo of the right hippocampus was negatively correlated with the Mini-Mental State Examination (MMSE) score (r = −0.434, p = 0.027), and the ReHo of the right middle temporal gyrus was positively correlated with MMSE score (r = 0.392, p = 0.048).ConclusionFunctional changes in multiple brain regions rather than in a single brain region have been observed in patients with aMCI. The abnormal activity of multiple specific brain regions may be a manifestation of impaired central function in patients with aMCI.

Episodic memory network characteristics in patients with amnestic mild cognitive impairment accompanied by executive function impairment

“…The result proved that the left STG is a shared substrate for auditory short-term memory and speech comprehension (Leff et al, 2009). Yue et al also found alterations in the amplitude of low frequency fluctuation in the STG of aMCI patients, positively correlated with MoCA scores, proposing that abnormalities in the STG might be related to dysfunction across multiple cognitive domains, consistent with the findings of this study (Yue et al, 2023). Furthermore, ROC analysis demonstrated that the FC of the left STG contributes to distinguishing aMCI with different levels of EF.…”

“…Amnestic mild cognitive impairment (aMCI), which serves as a prodromal stage of Alzheimer's disease (AD), is considered an intermediate stage between normal aging and AD (W. Bai et al., 2022 ; Petersen et al., 2014 ). The core characteristic of aMCI is a decline in episodic memory (EM) function, closely associated with disease progression (Cova et al., 2017 ; Grande et al., 2021 ; Yue et al., 2023 ). Statistics indicate that approximately 10%–15% of aMCI patients convert to AD each year (Jessen et al., 2014 ).…”

A potential brain functional biomarker distinguishing patients with Crohn’s disease with different disease stages: a resting-state fMRI study

“…This may be due to the fact that the sample size of this study was the largest of any published articles on rs-fMRI in patients with CD. The function of these brain regions is important for cognitive and emotional regulation ( Li et al, 2021b ; Yue et al, 2023 ; Zhao et al, 2023 ). Our neuroimaging findings may provide a neurophysiological substrate that may potentially explain the symptoms of psychological impairment observed in patients with CD, beyond the inflammatory stage.…”