Abstract
Individuals with mild cognitive impairment (MCI) are at high risk of developing Alzheimer’s disease (AD). Repetitive photic stimulation (PS) is commonly used in routine electroencephalogram (EEG) examinations for rapid assessment of perceptual functioning. This study aimed to evaluate neural oscillatory responses and nonlinear brain dynamics under the effects of PS in patients with mild AD, moderate AD, severe AD, and MCI, as well as healthy elderly controls (HC). EEG power ratios during PS were estimated as an index of oscillatory responses. Multiscale sample entropy (MSE) was estimated as an index of brain dynamics before, during, and after PS. During PS, EEG harmonic responses were lower and MSE values were higher in the AD subgroups than in HC and MCI groups. PS-induced changes in EEG complexity were less pronounced in the AD subgroups than in HC and MCI groups. Brain dynamics revealed a “transitional change” between MCI and Mild AD. Our findings suggest a deficiency in brain adaptability in AD patients, which hinders their ability to adapt to repetitive perceptual stimulation. This study highlights the importance of combining spectral and nonlinear dynamical analysis when seeking to unravel perceptual functioning and brain adaptability in the various stages of neurodegenerative diseases.
Highlights
Alzheimer’s disease (AD) is an irreversible neurodegenerative disorder and the most prevalent form of dementia [1]
Post-hoc comparisons revealed that the healthy elderly controls (HC) group was significantly younger than the Moderate AD group (Bonferroni-corrected p = 0.035), and the mild cognitive impairment (MCI) group was significantly younger than the Mild AD (Bonferronicorrected p = 0.005) and Moderate AD (Bonferroni-corrected p < 0.001) groups
This study investigated neural oscillatory responses and brain dynamics induced by intermittent photic stimulation in patients with MCI, mild AD, moderate AD, and severe
Summary
Alzheimer’s disease (AD) is an irreversible neurodegenerative disorder and the most prevalent form of dementia [1]. Brain deterioration in AD patients is characterized by the accumulation of β-amyloid plaques and neurofibrillary tangles consisting of tau amyloid fibrils, which can cause local neuronal death, neurotransmitter deficiencies [2], and cortical disconnection [3]. AD patients suffer from declining memory and cognitive functions as well as functional disabilities. Is a clinical neuropsychological syndrome characterized by cognitive and memory impairments [4]. Most MCI patients retain the functional abilities required to perform daily activities; they face an elevated risk for AD, with a progression rate of 10% to. Magnetic resonance imaging (MRI) and positron emission tomography (PET) are commonly used to investigate the neuropathology in AD and MCI patients [6,7]; these methods are costly and inaccessible to many patients.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
