Spatio-temporal dynamics of alpha brain electric fields, and cognitive modes

Area of Science:

• Neuroscience
• Cognitive Science
• Brain Electric Activity Analysis

Background:

• Brain electric activity is typically analyzed as continuous.
• Understanding the discrete nature of brain activity is crucial for cognitive processes.

Purpose of the Study:

• To investigate the microstate structure of brain electric fields.
• To correlate distinct mentation modes with specific brain electric microstates.

Main Methods:

• Frequency-domain source modeling.
• State-space trajectory complexity estimation.
• Microstate parsing of electroencephalography (EEG) data.
• Analysis of both input-driven and spontaneous mentation.

Main Results:

• Alpha EEG field strength is influenced by visual and abstract mentation.
• Different neuronal populations and brain locations generate distinct temporal frequencies.
• Specific alpha frequencies correlate with different brain functions and mentation profiles.
• Brain activity is discontinuous, characterized by global microstates and rapid transitions.
• Distinct mentation modes are associated with unique brain electric microstates.

Conclusions:

• Brain electric fields exhibit a microstate structure in the sub-second range.
• These microstates represent quasi-stable field topographies with rapid transitions.
• Brain electric microstates are proposed as fundamental units of thought.
• This microstate framework offers a new perspective on cognitive processes.