Investigating Nuisance Effects Induced in EEG During tACS Application

Area of Science:

• Neuroscience
• Biomedical Engineering
• Signal Processing

Background:

• Transcranial alternating-current stimulation (tACS) is a common technique for studying brain function by entraining neuronal oscillations.
• High-intensity stimulation signals and associated artifacts in electroencephalogram (EEG) data pose significant challenges for accurate analysis.
• Existing methods struggle to effectively remove harmonic, non-harmonic, and higher-order artifacts induced during tACS.

Purpose of the Study:

• To address the non-trivial problem of artifact removal in EEG data acquired during tACS.
• To discuss the challenges and present methodological approaches for artifact mitigation.
• To illustrate artifact induction mechanisms and removal strategies using experimental data.

Main Methods:

• Utilizing data from a schematic demonstrator setup to understand artifact generation.
• Analyzing human-subject EEG data recorded during tACS.
• Developing and discussing specific methodological strategies for artifact removal.

Main Results:

• Identified mechanisms of artifact induction during tACS.
• Demonstrated the effectiveness of proposed strategies in removing stimulation artifacts.
• Validated artifact removal techniques on both simulated and real-world human data.

Conclusions:

• Effective removal of tACS-induced artifacts from EEG is crucial for reliable brain function studies.
• The presented methodological approaches offer solutions to overcome common artifact challenges.
• This work provides valuable insights for researchers using tACS in conjunction with EEG.