Near-zero phase-lag hyperscanning in a novel wireless EEG system.

Area of Science:

• Neuroscience
• Biomedical Engineering
• Signal Processing

Background:

• Hyperscanning enables concurrent neural recording of multiple individuals to study social interactions.
• Wireless electroencephalography (EEG) offers mobility for naturalistic social interaction studies.
• Accurate temporal synchronization is crucial for reliable interbrain connectivity analysis in hyperscanning.

Purpose of the Study:

• To develop and validate a clock-synchronized method for precise temporal alignment of wireless EEG signals in hyperscanning.
• To prevent timing errors in interbrain connectivity estimation caused by asynchronous sampling.

Main Methods:

• A custom RJ45 cable synchronizes sampling clocks across multiple wireless EEG amplifiers.
• Analog-to-digital converters are driven by a unified sampling clock.
• Radio frequency channels update dongle counters for accurate event marker timestamping.

Main Results:

• The proposed method ensures synchronous sampling across multiple EEG devices.
• Near-zero phase lag and negligible amplitude differences were achieved between synchronized signals.
• Simulations and a video gaming experiment validated the method's effectiveness.

Conclusions:

• The clock-synchronized method is a promising solution for wireless EEG hyperscanning.
• This technique enables precise assessment of interbrain couplings during social interactions.
• It facilitates more accurate studies of the neural basis of social behavior.