Analysis of EEG changes between the frontal and occipital cortex during speech

Area of Science:

• Neuroscience
• Cognitive Science
• Signal Processing

Background:

• Understanding brain activity during speech is crucial for deciphering language processing.
• Previous methods for analyzing electroencephalography (EEG) signals have limitations in capturing dynamic inter-regional communication.

Purpose of the Study:

• To propose and discuss a bidirectional communication model between frontal and occipital cortices.
• To quantitatively investigate directed information flow between these regions during speech using EEG.
• To assess the feasibility of spatiotemporal analysis for EEG signals in language processes.

Main Methods:

• Applied time series analysis and entropy analysis to EEG data from 11 subjects.
• Calculated transinformation with directionality between frontal and occipital areas.
• Utilized spatiotemporal analysis to interpret information changes during speech.

Main Results:

• Identified a dominant information flow from the occipital to frontal cortex immediately before speech, primarily in the right hemisphere.
• Observed a sustained occipital-frontal information flow during speech in both hemispheres.
• Demonstrated the feasibility of the developed method for analyzing EEG in language tasks.

Conclusions:

• The proposed bidirectional communication model provides insights into frontal-occipital interactions during speech.
• Spatiotemporal analysis of EEG signals is a viable technique for studying neural correlates of language.
• The findings highlight hemispheric differences in information processing preceding and during speech.