Factors affecting the stimulus artifact tail in surface-recorded somatosensory-evoked potentials

Area of Science:

• Biomedical Engineering
• Neuroscience
• Signal Processing

Background:

• Surface-recorded somatosensory-evoked potentials (SEPs) are crucial for assessing neural pathway integrity.
• Electrical stimulation artifacts can obscure SEPs, hindering accurate latency measurements.

Purpose of the Study:

• To identify factors influencing the artifact tail in electrically evoked SEPs.
• To develop a novel model for predicting and mitigating stimulation artifacts.

Main Methods:

• Developed a lumped electrical circuit model for artifact generation.
• Utilized autoregressive moving average (ARMA) and artificial neural networks (ANNs) for tissue parameter estimation.
• Integrated tissue and electrode-skin interface models within Simulink.

Main Results:

• Stimulation electrode-skin impedance significantly impacts artifact tail duration.
• The properties of body tissue under recording electrodes critically affect artifact appearance.
• Model simulations were validated with experimental median nerve SEP data.

Conclusions:

• Low series capacitance stimulation electrodes are recommended to shorten artifact tails.
• Accurate modeling of tissue and electrode interfaces is essential for artifact reduction.
• This approach enhances the reliability of SEP measurements in clinical and research settings.