Differentiation with electroencephalography microstate in temporal lobe epilepsy with and without cognitive decline

Area of Science:

• Neuroscience
• Neurology
• Psychiatry

Background:

• Electroencephalography (EEG) microstate analysis is a valuable tool for studying neurological and psychiatric disorders.
• Temporal Lobe Epilepsy (TLE) is often associated with cognitive decline, necessitating reliable biomarkers.
• Understanding EEG microstate alterations in TLE patients can offer insights into cognitive impairment mechanisms.

Purpose of the Study:

• To investigate alterations in EEG microstates in temporal lobe epilepsy (TLE) patients.
• To differentiate EEG microstate characteristics between TLE patients with and without cognitive decline.
• To identify potential neurophysiological markers for cognitive decline in TLE.

Main Methods:

• Inclusion of 47 TLE patients (with/without cognitive decline) and 14 healthy controls (HCs).
• 64-channel EEG monitoring with microstate analysis on 2-minute eye-closed awake epochs.
• Group division based on Wechsler Intelligence Scale scores (normal cognition IQ ≥ 90, abnormal cognition IQ < 90).
• Frequency spectral analysis (delta, theta, alpha, beta bands) and microstate parameter extraction (duration, coverage, occurrence, transition probability).
• Statistical analysis using multivariate analysis of variance (MANOVA) with Bonferroni correction.

Main Results:

• Significant differences in beta sub-band EEG microstates were observed among the groups.
• TLE patients with abnormal cognition exhibited increased occurrence of Map-D and higher transition probabilities to Map-D from Maps A, B, and C.
• Frequency spectral analysis showed no significant power differences across all sub-bands among the three groups.

Conclusions:

• Beta sub-band EEG microstates, particularly Map-D characteristics, show potential as neurophysiological markers for cognitive decline in TLE.
• Microstate analysis in the beta frequency band can help identify cognitive impairment in TLE patients.
• These findings contribute to understanding the neurophysiological basis of cognitive deficits in TLE.