Screening for Alzheimer's disease using prefrontal resting-state functional near-infrared spectroscopy

Abstract

IntroductionAlzheimer's disease (AD) is neurodegenerative dementia that causes neurovascular dysfunction and cognitive impairment. Currently, 50 million people live with dementia worldwide, and there are nearly 10 million new cases every year. There is a need for relatively less costly and more objective methods of screening and early diagnosis.MethodsFunctional near-infrared spectroscopy (fNIRS) systems are a promising solution for the early Detection of AD. For a practical clinically relevant system, a smaller number of optimally placed channels are clearly preferable. In this study, we investigated the number and locations of the best-performing fNIRS channels measuring prefrontal cortex activations. Twenty-one subjects diagnosed with AD and eighteen healthy controls were recruited for the study.ResultsWe have shown that resting-state fNIRS recordings from a small number of prefrontal locations provide a promising methodology for detecting AD and monitoring its progression. A high-density continuous-wave fNIRS system was first used to verify the relatively lower hemodynamic activity in the prefrontal cortical areas observed in patients with AD. By using the episode averaged standard deviation of the oxyhemoglobin concentration changes as features that were fed into a Support Vector Machine; we then showed that the accuracy of subsets of optical channels in predicting the presence and severity of AD was significantly above chance. The results suggest that AD can be detected with a 0.76 sensitivity score and a 0.68 specificity score while the severity of AD could be detected with a 0.75 sensitivity score and a 0.72 specificity score with ≤5 channels.DiscussionThese scores suggest that fNIRS is a viable technology for conveniently detecting and monitoring AD as well as investigating underlying mechanisms of disease progression.

Assessing the consistency and sensitivity of the neural correlates of narrative stimuli using functional near-infrared spectroscopy

“…Notably, fNIRS has the distinct advantage of being administered directly at a patient's bedside, enabling measurement of both neonatal (Mitra et al, 2020;Tang et al, 2024) and adult populations (Bicciato et al, 2022) within the intensive care unit. In addition, fNIRS has been used to measure neural activity in patients with neurodegenerative diseases in scenarios where fMRI is impractical or potentially detrimental, including amyotrophic lateral sclerosis (Kuruvilla et al, 2013), Alzheimer's disease (Blum et al, 2022;Keles et al, 2022), and in chronic disorders of consciousness patients (Abdalmalak et al, 2020). Future studies should consider having these patients watch or listen to movie narratives, as it enables the further exploration of higher-order cognitive processes with minimal time and effort.…”

“…Owing to its main features, such as affordability, portability, and versatility, fNIRS holds great potential to be applied to pediatric and neonatal (Peng & Hou, 2021;Tang et al, 2024), neurodegenerative (Blum et al, 2022;Kuruvilla et al, 2013;Keles et al, 2022), and critically brain-injured (Abdalmalak et al, 2020;Bicciato et al, 2022;Wang et al, 2022;Shu et al, 2023) populations, as well as naturalistic paradigms more broadly (see Pinti et al, 2018 for a review).…”

Investigation of hemispheric asymmetry in Alzheimer’s disease patients during resting state revealed by fNIRS

“…Most studies have reported changes in resting cerebral oxygenation levels, fluctuations, or connectivity in patients with Alzheimer's and Mild cognitive impairment 26 . A recent study has shown that fNIRS is a suitable technology for detecting AD and monitoring its progression 27 .…”