Criteria necessary to score an arousal in NREM sleep include all of the following EXCEPT:

Criteria necessary to score an arousal in NREM sleep include all of the following EXCEPT:

• A. A concurrent increase in chin EMG
• B. 10 seconds of sleep prior to the arousal
• C. The arousal must last at least 3 seconds
• D. Frequencies greater than 16 Hz, which are not spindles, must occur

Answer: (A)

In NREM sleep scoring, an arousal is identified by an abrupt shift in EEG to higher-frequency activity that lasts at least 3 seconds, and it is typically preceded by about 10 seconds of continuous sleep. The post-arousal EEG should show frequencies greater than 16 Hz (not spindles), indicating a return toward lighter sleep or wakefulness. The chin EMG does not have to increase for an event to be scored as an arousal; EMG changes may occur but are not a required part of the criteria. That’s why the statement about a concurrent increase in chin EMG is the one that doesn’t fit the criteria.

In NREM sleep scoring, an arousal is identified by an abrupt shift in EEG to higher-frequency activity that lasts at least 3 seconds, and it is typically preceded by about 10 seconds of continuous sleep. The post-arousal EEG should show frequencies greater than 16 Hz (not spindles), indicating a return toward lighter sleep or wakefulness. The chin EMG does not have to increase for an event to be scored as an arousal; EMG changes may occur but are not a required part of the criteria. That’s why the statement about a concurrent increase in chin EMG is the one that doesn’t fit the criteria.