What should be done if a slow wave artifact appears in three EEG channels sharing a common reference?

Changing the input signal derivation to a backup reference electrode is an appropriate action when dealing with slow wave artifacts that appear in multiple EEG channels sharing a common reference. This approach helps to minimize the influence of artifacts that may be affecting the common reference point. By utilizing a different reference electrode, you can effectively isolate the specific brain activity being recorded and mitigate interference from the slow wave artifact.

In situations where a common reference is used, artifacts can propagate across channels, compromising data integrity. By employing a backup reference electrode that is not affected by the same slow wave activity, the recordings can produce a cleaner EEG signal. This method enhances the accuracy of interpreting the EEG results as it reduces the chances of misrepresenting brain activity due to the artifact.

Alternatively, other strategies such as double referencing can introduce their own challenges, especially if they’re not conducive to the clinical context or if the anatomical positioning of electrodes is not optimal. Raising low-frequency filters could diminish the physiological slow waves of interest, potentially leading to the loss of essential data instead of clarifying the EEG recordings. Therefore, utilizing a backup reference electrode is the most effective and reliable method for addressing slow wave artifacts in this context.