RPSGT Core Concepts & Fundamentals 4 — Questions and Answers
Question 1: What is the AASM-defined minimum frequency for activity to qualify as a sleep spindle?
- 8 Hz
- 11 Hz (Correct answer)
- 16 Hz
- 20 Hz
Correct answer: 11 Hz
AASM defines sleep spindles as bursts of 11–16 Hz activity lasting 0.5–3 seconds.
Question 2: Which of the following is the correct electrode derivation used to record the central EEG in standard PSG per AASM?
- Fp1-A1
- C4-M1 (Correct answer)
- O1-A2
- F4-M1
Correct answer: C4-M1
AASM recommends C4-M1 (with backup C3-M2) as the central EEG derivation for sleep staging.
Question 3: Slow-wave sleep (SWS) consists of which AASM sleep stage(s)?
- N1 only
- N1 and N2
- N3 only (Correct answer)
- N2 and N3
Correct answer: N3 only
Under AASM guidelines, Stage N3 is equivalent to slow-wave sleep (formerly stages 3 and 4 combined).
Question 4: An arousal in PSG is defined as an abrupt shift in EEG frequency lasting at least how long?
- 1 second
- 3 seconds (Correct answer)
- 5 seconds
- 10 seconds
Correct answer: 3 seconds
AASM defines an arousal as an abrupt EEG frequency shift lasting at least 3 seconds, preceded by at least 10 seconds of sleep.
Question 5: What does the term 'hypnogram' represent in polysomnography?
- A graphic display of oxygen saturation over the night
- A chart showing sleep stage progression across the recording period (Correct answer)
- The raw EEG tracing from the entire night
- A summary of apnea-hypopnea events by body position
Correct answer: A chart showing sleep stage progression across the recording period
A hypnogram is a visual summary graph plotting sleep stages on the Y-axis against time on the X-axis across the recording.
Question 6: According to AASM rules, how much NREM sleep must precede a scored arousal?
- 5 seconds
- 10 seconds (Correct answer)
- 30 seconds
- 60 seconds
Correct answer: 10 seconds
At least 10 consecutive seconds of sleep must precede an EEG frequency shift for it to be scored as an arousal.
Question 7: Which sleep stage typically has the highest threshold for arousal by external stimuli?
- Stage W
- Stage N1
- Stage N2
- Stage N3 (Correct answer)
Correct answer: Stage N3
Stage N3 (slow-wave sleep) has the highest arousal threshold, making it the most difficult stage from which to awaken someone.
RPSGT Core Concepts & Fundamentals 4
What is the AASM-defined minimum frequency for activity to qualify as a sleep spindle?