What is a common cause of pulse artifacts in EEG recordings?

Pulse artifacts in EEG recordings are often caused by the placement of electrodes over a blood vessel. When electrodes are positioned over or near a vessel, the pulsations of the blood flow can create electrical signals that are recorded in the EEG. These signals can mask the true brain activity, leading to misleading readings or artifacts in the collected data. This phenomenon occurs because the rhythmic nature of the pulse generates a continuous electrical signal that can interfere with the analysis of neural activity.

Proper electrode placement is critical in minimizing such artifacts, as accurate positioning ensures that the electrodes primarily pick up electrical activity from the brain rather than from physiological processes like blood flow. Understanding the anatomy and physiology associated with blood vessels in relation to the scalp can help practitioners make informed decisions about where to place electrodes to achieve cleaner EEG data.