Alterations of Graphic Properties and Related Cognitive Functioning Changes in Mild Alzheimer’s Disease Revealed by Individual Morphological Brain Network

Abstract

Alzheimer’s disease (AD) is one of the most common forms of dementia that has slowly negative impacts on memory and cognition. With the assistance of multimodal brain networks and graph-based analysis approaches, AD-related network disruptions support the hypothesis that AD can be identified as a dysconnectivity syndrome. However, as the recent emerging of individual-based morphological network research of AD, the utilization of multiple morphometric features may provide a broader horizon for locating the lesions. Therefore, the present study applied the newly proposed individual morphological brain network with five commonly used morphometric features (cortical thickness, regional volume, surface area, mean curvature, and fold index) to explore the topological aberrations and their relationship with cognitive functioning alterations in the early stage of AD. A total of 40 right-handed participants were selected from Open Access Series of Imaging Studies Database with 20 AD patients (age ranged from 70 to 79, CDR = 0.5) and 20 age/gender-matched healthy controls. The significantly affected connections (p < 0.05 with FDR correction) were observed across multiple regions, both enhanced and attenuated correlations, primarily related to the left entorhinal cortex (ENT). In addition, profoundly changed Mini Mental State Examination (MMSE) score and global efficiency (p < 0.05) were noted in the AD patients, as well as the pronounced inter-group distinctions of betweenness centrality, global and local efficiency (p < 0.05) in the higher MMSE score zone (28–30), which indicating the potential role of graphic properties in determination of early-stage AD patients. Moreover, the reservations (regions in the occipital and frontal lobes) and alterations (regions in the right temporal lobe and cingulate cortex) of hubs were also detected in the AD patients. Overall, the findings further confirm the selective AD-related disruptions in morphological brain networks and also suggest the feasibility of applying the morphological graphic properties in the discrimination of early-stage AD patients.

Brain Structural Network Compensation Is Associated With Cognitive Impairment and Alzheimer’s Disease Pathology

“…Furthermore, our study may reflect reorganization and high resilience to network integrity damage. Previous studies evaluating graph theoretical properties have described compensation at the level of hippocampal/parahippocampal regions and the frontal and occipital lobes (van Duinkerken et al, 2016;Li et al, 2018). In line with prior studies, in our analysis, network integrity was widely increased due to the compensation in specific nodes related to cognition.…”

Functional connectome of arousal and motor brainstem nuclei in living humans by 7 Tesla resting-state fMRI

“…The human brain network is considered to have small-world network properties, which indicate that the brain is organized into both local cliques and global integration. Graph measure analysis has been used (Bullmore and Sporns, 2009;Kim et al, 2019;Nakamura et al, 2009) to explore disease induced alteration in topological parameters of the human brain functional connectivity (Li et al, 2018). Global (which was not certified by peer review) is the author/funder.…”

Connectome analysis of brain functional network alterations in breast cancer survivors with and without chemotherapy

“…Graph theoretical approaches have been applied in exploring Alzheimer disease, schizophrenia, and traumatic brain injury [8][9][10]. Alteration in topological parameters implies that illness may alter human brain connectivity and suggests that cognitive symptoms and functional deficits are the disturbance of the functional network [11].…”