Functional MRI technologies in the study of medication treatment effect on Alzheimer's disease

Abstract

Alzheimer's disease (AD) is the most common cause of late-life dementia. Characterized by progressive neurodegeneration, the disease is expressed as gradual memory loss together with decline in cognitive abilities and other brain functions. Despite extensive research over the past decade, the cause and cure of AD both remain largely unknown. Several AD-associated deficits have been targeted for interventions, including those based on amyloid-beta, tau, and inflammation hypotheses. Only 2 types of medications-cholinesterase inhibitors and memantine-have been approved, to control the cognitive symptoms of AD such as the loss of memory, language, and executive function. Noninvasive in vivo functional magnetic resonance imaging (MRI) technologies, including the blood oxygen level-dependent functional MRI, arterial spin labeling-based perfusion MRI, and the proton magnetic resonance spectroscopy have been used to study the effect of ChEIs and memantine in the brain. Most of these studies have demonstrated increased functional activation and connectivity, increased regional brain blood flow and volume post-treatment, and positive responses of critical brain metabolites reflecting neuronal status and functionality in patients with AD and mild cognitive impairment. The findings have contributed to the understanding of the mechanisms underlying the medication treatments and support the crucial role of functional MRI technologies in the development and refinement of AD medication therapies.

New approaches to symptomatic treatments for Alzheimer’s disease

“…Cognition is dependent on intact circuit function that includes cholinergic innervation as well as involvement of other transmitters. Imaging investigations such as those with functional magnetic resonance imaging (fMRI) and fluorodeoxyglucose (FDG) positron emission tomography (PET) typically show enhanced cortical circuit activity following treatment with ChE-Is [ 16 , 17 ]. Enhancement of circuit function is a goal of cognitive-enhancing therapies and new imaging tools may assist in the search for more effective treatments [ 18 ].…”

Functional MRI evaluation of cognitive effects of carotid stenosis revascularization

“…FMRI has been widely used to study cognitive changes and treatment effects across disease conditions (Guo et al., 2018 ). However, there is limited knowledge about using fMRI in accessing cognitive effects of clinical revascularization in treating carotid stenosis.…”

Visual-Saliency-Based Abnormality Detection for MRI Brain Images—Alzheimer’s Disease Analysis

“…Figure 1 shows MRI images of a healthy person and a person suffering from dementia. [9,10]. Joint regression and classification [11] and weighted multi-modality-based classification [12] are mainly used to classify the disease.…”

“…This is one of the significant differences between deep-learning-based methods and other state-of-the-art machine learning methods. [9,10]. Joint regression and classification [11] and weighted multi-modality-based classification [12] are mainly used to classify the disease.…”

“…Several classification methods for AD have recently been reported. Calhoun et al and Guo et al reviewed Alzheimer's disease classification based on MRI data[9,10]. Joint regression and classification[11] and weighted multi-modality-based classification[12] are mainly used to classify the disease.…”