Correlation between cerebral hemodynamic functional near-infrared spectroscopy and positron emission tomography for assessing mild cognitive impairment and Alzheimer’s disease: An exploratory study

Abstract

This study was performed to investigate the usefulness of functional near-infrared spectroscopy (fNIRS) by conducting a comparative analysis of hemodynamic activation detected by fNIRS and positron emission tomography (PET) and magnetic resonance imaging (MRI) in patients with mild cognitive impairment (MCI) and Alzheimer’s disease (AD). Participants were divided into four groups: the subjective memory impairment (SMI), amnestic MCI (aMCI), non-amnestic MCI (naMCI), and AD groups. We recorded the hemodynamic response during the semantic verbal fluency task (SVFT) using a commercial wireless continuous-wave NIRS system. The correlation between the parameters of the neuroimaging assessments among the groups was analyzed. Region of interest-based comparisons showed that the four groups had significantly different hemodynamic responses during SVFT in the bilateral dorsolateral prefrontal cortex (DLPFC). The linear mixed effect model result indicates that the mean ΔHbO2 from the bilateral DLPFC regions showed a significant positive correlation to the overall FDG-PET after controlling for age and group differences in the fNIRS signals. Amyloid PET signals tended to better differentiate the AD group from other groups, and fNIRS signals tended to better differentiate the SMI group from other groups. In addition, a comparison between the group pairs revealed a mirrored pattern between the hippocampal volume and hemodynamic response in the DLPFC. The hemodynamic response detected by fNIRS showed a significant correlation with metabolic and anatomical changes associated with disease progression. Therefore, fNIRS may be considered as a screening tool to predict the hemodynamic and metabolic statuses of the brain in patients with MCI and AD.

Characterization of Brain Regions Based on Event-related Potentials—N400 Component

“…Along with continued advances in neuroscience techniques, such as functional magnetic resonance imaging and near-infrared spectroscopy, research on the N400 is expected to enter a more in-depth and innovative phase [12] . It is expected that future studies will focus more on the deep neural mechanisms of the N400, its interaction with other cognitive functions, and its specificity in specific populations (e.g., bilinguals, people with language disorders, etc.).…”

Light on Alzheimer’s disease: from basic insights to preclinical studies

“…It has the capability to offer details about the cerebral glucose metabolism rate during periods of rest, serving as an indicator of neural activity. Several research studies have illustrated that unique patterns of cerebral glucose metabolism can reliably distinguish AD from other disorders leading to dementia ( Mosconi, 2013 ; Kantarci, 2014 ; Insel et al, 2023 ; Yoon et al, 2023 ). Furthermore, PET imaging, utilizing specific tracers, can visualize the cerebral Aβ deposition, assisting in distinguishing dementia syndromes ( Kantarci, 2014 ).…”