What filter is best for filtering out slow waves resulting from sweat artifacts?

The correct choice for filtering out slow waves resulting from sweat artifacts is the low-frequency filter set at 5 Hz (LFF 5Hz). This filter helps in eliminating low-frequency noise, such as slow waves that can occur due to skin potential changes and other physiological factors, including sweat artifacts.

Artifacts often manifest as slow waves, and a low-frequency filter can help distinguish brain activity from these extraneous signals. By setting the filter at 5 Hz, it effectively reduces the influence of any slow waves while preserving the essential components of the EEG signal above this threshold, which includes critical brain wave activity such as delta and theta rhythms.

Using a higher low-frequency filter (such as LFF 1Hz) could lead to retaining both the unwanted slow waves and important EEG information, whereas a high-frequency filter (HFF) does not specifically target the slow waves caused by artifacts but rather attenuates faster brain activity. A high-frequency filter set at 15 Hz or 70 Hz is designed for removing higher frequency noise rather than slow waves, making them less appropriate for this particular scenario.