Slow rolling eye movements during stage N1 sleep will best be seen at what low filter setting?

Slow rolling eye movements are characteristic of stage N1 sleep and are best captured at a low filter setting that allows for the detection of these gradual changes in eye position. A filter setting around 0.3 Hz is optimal because it balances the need to reduce high-frequency noise while still allowing the slow, low-frequency eye movements to be visible on the polysomnographic recording. This specific filter setting effectively isolates the signals of interest without overly attenuating the slow rolling movements which are essential for accurate interpretation of sleep stages and associated physiological phenomena. A lower filter setting, such as 0.1 Hz, may introduce excessive low-frequency artifacts, while higher settings like 0.5 Hz or 1.0 Hz could filter out significant portions of the slow-moving eye activity, making them less recognizable. Therefore, the choice of 0.3 Hz maximizes the clarity of these movements during data analysis in a sleep study.