Carbon-wire loop based artifact correction outperforms post-processing EEG/fMRI corrections--A validation of a...

Area of Science:

• Neuroimaging
• Biomedical Engineering
• Signal Processing

Background:

• Simultaneous electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) are powerful neuroimaging techniques.
• EEG signals acquire severe artifacts in MRI environments, including MR scanning, blood-pulsation, and helium pump artifacts.
• Current artifact removal strategies are insufficient, often requiring helium pump deactivation, risking MRI system damage and increasing costs.

Purpose of the Study:

• To introduce a novel artifact correction method for simultaneous EEG-fMRI.
• To address both helium pump and ballisto-cardiac artifacts (BCG).
• To evaluate the effectiveness of the new method compared to conventional techniques.

Main Methods:

• Development of carbon-wire loops (CWL) as additional sensors to track unpredictable artifacts.
• Creation of an EEGLAB plugin for artifact correction using CWL data.
• Comparison of signal-to-noise ratios (SNR) of EEG data corrected with CWL versus three conventional methods.
• Evaluation metrics included EEG signal quality, eyes open/closed effects, and impact on EEG-BOLD correlations.

Main Results:

• The CWL correction method effectively removes helium pump artifacts.
• EEG data corrected with CWL showed improved quality, comparable to EEG acquired outside the MRI environment.
• The CWL method demonstrated superior performance over conventional post-processing techniques.
• Real-time correction capability was confirmed, suitable for neurofeedback and time-locked stimulation.

Conclusions:

• The novel CWL method offers a robust solution for correcting helium pump and BCG artifacts in simultaneous EEG-fMRI.
• This technique enhances EEG data quality, enabling more reliable analysis and broader application of combined EEG-fMRI.
• CWL facilitates real-time artifact correction, crucial for time-sensitive neuroimaging applications.