What artifact refers to interference typically at 60Hz?

The correct answer is line noise, which refers to electrical interference that usually manifests as a 60Hz hum in the context of sleep studies and other electronic recordings. This interference typically originates from electrical power sources and can contaminate the data collected from physiological signals, such as EEG or EKG, making it difficult to interpret the true signals.

Line noise can pose significant challenges in sleep studies; it may mask important electrical activity related to sleep patterns and other phenomena. Identifying and mitigating line noise is crucial in ensuring the accuracy of the recorded data, which is why this term is emphasized in sleep disorder assessments.

Other potential options, while relevant in their contexts, do not pertain specifically to the type of interference described here. White noise refers to a consistent sound across various frequencies that is often used therapeutically to provide a masking effect. Signal jitter describes variations in signal timing, often due to digital signal processing issues, and phase shift involves a time delay between signal components. These terms do not specifically characterize the 60Hz interference that defines line noise.