Biomarkers

Area of Science:

• Neuroscience
• Gerontology
• Biomedical Engineering

Background:

• Functional decline in daily activities is a hallmark of dementia syndromes.
• Subtle limitations precede mild cognitive impairment (MCI) diagnosis.
• Neural underpinnings of early-stage dementia-related functional decline are poorly understood.

Purpose of the Study:

• Investigate neural correlates of functional decline in older adults at varying cognitive impairment (CI) risk.
• Utilize a dual-task walking paradigm with electroencephalography (EEG) and 3D body tracking.
• Identify distinct brain activation patterns associated with higher CI risk during complex tasks.

Main Methods:

• Recruited 36 individuals aged 65+, divided into lower-risk (Montreal Cognitive Assessment [MoCA] ≥ 27) and higher-risk (MoCA ≤ 26) groups.
• Employed a dual-task walking paradigm synchronized with portable EEG and 3D body tracking.
• Analyzed gait-related brain activity: 8-28 Hz over pre/postcentral gyrus (sensorimotor) and 3-7 Hz over frontomedial cortex (motor control).

Main Results:

• Higher CI risk was associated with poorer performance during dual-task walking.
• Distinct fronto-parietal brain activation patterns were observed in the higher-risk group.
• Specific EEG frequency bands over sensorimotor and motor control regions differentiated risk groups.

Conclusions:

• The combined EEG and 3D motion tracking approach offers high spatiotemporal resolution for analyzing brain activity during complex daily functions.
• This methodology provides task-specific, brain regional, and spectral insights into early functional decline.
• The approach has potential for improving prediction and identifying non-invasive brain stimulation targets for early dementia interventions.