Biomarkers

Area of Science:

• Neuroscience
• Medical Imaging
• Biomarkers

Background:

• Alzheimer's disease (AD) is characterized by cognitive decline, synaptic loss, and amyloid/tau pathology.
• Early detection of AD requires sensitive and reliable biomarkers for clinical trials.
• Magneto/electroencephalography (M/EEG) can measure brain function changes in AD.

Purpose of the Study:

• To test the sensitivity and reliability of M/EEG biomarkers for AD detection.
• To develop a hybrid audio-visual oddball (VAB) task to measure neural responses.
• To assess M/EEG's suitability for experimental medicine studies in AD.

Main Methods:

• Concurrent M/EEG was used to record neural responses to auditory novelty and image-sound pairing mismatches.
• Participants included cognitively healthy older adults (N=31) and individuals with amyloid-positive mild cognitive impairment (MCI) or early AD (N=55).
• Test-retest reliability of the VAB task was assessed in a subset of patients (N=17) over two weeks.

Main Results:

• Healthy controls exhibited stronger neural responses to novel sounds than mismatching sounds.
• AD/MCI patients showed increased neural responses to mismatching sounds, indicating impaired associative learning.
• The VAB task demonstrated moderate to good reliability for M/EEG measures over two weeks.

Conclusions:

• MEG responses in the VAB task are sensitive to the presence of AD/MCI.
• The VAB task, using MEG, shows potential as a reliable biomarker for AD/MCI.
• MEG is suitable for supporting experimental medicine studies in AD/MCI detection and progression.