High-density EEG microstates for functional evaluation of visual pathway in multiple sclerosis: a correlation study...

Area of Science:

• Neuroscience
• Clinical Neurology
• Biomedical Engineering

Background:

• Multiple sclerosis (MS) frequently causes visual pathway dysfunction.
• Visual evoked potentials (VEPs) are standard for assessing visual pathway integrity.
• High-density EEG (hdEEG) microstate analysis provides insights into resting-state neural dynamics.

Purpose of the Study:

• To investigate visual pathway alterations in relapsing-remitting MS (RRMS) using hdEEG microstate analysis, focusing on the Map-B microstate.
• To compare hdEEG microstate findings with conventional VEP parameters in RRMS patients.

Main Methods:

• Twenty-two RRMS patients underwent hdEEG recording and VEP testing.
• Microstate analysis segmented dominant brain electrical activity patterns.
• Temporal parameters of microstates (duration, frequency, time coverage, GEV) and VEP measures (latencies, dispersion, amplitude) were computed.

Main Results:

• A negative correlation was observed between VEP N75-N145 dispersion and Map-B global explained variance (GEV) and frequency.
• In patients with normal VEP N75-N145 dispersion, Map-B expression positively correlated with P100 and N145 latencies.

Conclusions:

• Altered temporal dynamics of the Map-B microstate are indicative of visual pathway dysfunction in RRMS.
• hdEEG microstate analysis serves as a valuable, non-invasive method for evaluating resting-state visual cortical function in MS, complementing VEPs.