RPSGT RPSGT Sleep Staging & Scoring — Questions and Answers

Question 1: According to AASM scoring rules, what percentage of an epoch must consist of slow wave activity to score Stage N3?

≥10%
≥20% (Correct answer)
≥30%
≥50%

Correct answer: ≥20%

AASM rules require that ≥20% of the epoch consist of slow wave activity (0.5–2 Hz, >75 µV frontal) to score Stage N3.

Question 2: What is the typical frequency range for sleep spindles used when scoring Stage N2?

4–7 Hz
8–10 Hz
11–16 Hz (Correct answer)
18–25 Hz

Correct answer: 11–16 Hz

Sleep spindles are defined as 11–16 Hz (typically 12–14 Hz) waxing-and-waning activity lasting ≥0.5 seconds.

Question 3: What is the minimum duration a K-complex must meet to satisfy AASM scoring criteria?

0.25 seconds
0.5 seconds (Correct answer)
0.75 seconds
1.0 second

Correct answer: 0.5 seconds

AASM requires a K-complex to have a total duration of ≥0.5 seconds.

Question 4: According to AASM guidelines, which electrode region is used to measure slow wave activity for N3 scoring?

Occipital (O1/O2)
Central (C3/C4)
Frontal (F3/F4) (Correct answer)
Temporal (T3/T4)

Correct answer: Frontal (F3/F4)

AASM specifies that slow wave activity amplitude and percentage are assessed over frontal derivations (F3 or F4).

Question 5: What is the standard epoch length used in polysomnography scoring per AASM guidelines?

20 seconds
30 seconds (Correct answer)
45 seconds
60 seconds

Correct answer: 30 seconds

The standard PSG epoch length is 30 seconds, established by Rechtschaffen & Kales and retained in AASM rules.

Question 6: During REM sleep, which chin EMG finding is expected on a polysomnogram?

High-amplitude tonic activity
Moderate activity with phasic bursts
Atonia with occasional phasic twitches (Correct answer)
Rhythmic jaw clenching

Correct answer: Atonia with occasional phasic twitches

REM sleep is characterized by chin EMG atonia (the lowest amplitude relative to other stages) with occasional phasic muscle twitches.

Question 7: According to AASM rules, an epoch is scored Stage Wake (W) when alpha activity occupies what proportion of the epoch?

≥20%
≥30%
≥50% (Correct answer)
≥75%

Correct answer: ≥50%

Stage W is scored when alpha activity is present for ≥50% of the epoch in subjects who generate occipital alpha.

Question 8: What is the minimum preceding sleep duration required before an EEG frequency shift can be scored as an arousal per AASM rules?

5 seconds
10 seconds (Correct answer)
15 seconds
30 seconds

Correct answer: 10 seconds

AASM requires at least 10 seconds of stable sleep preceding the EEG frequency shift for it to qualify as a scoreable arousal.

Question 9: Vertex sharp waves are most characteristic of which sleep stage?

N1 (Correct answer)
N2
N3
REM

Correct answer: N1

Vertex sharp waves — high-amplitude sharp transients maximal at the vertex — are a hallmark EEG feature of Stage N1.

Question 10: According to AASM guidelines, which combination of features is required to score an epoch as Stage REM?

Alpha EEG + rapid eye movements + high chin EMG
Low-amplitude mixed-frequency EEG + rapid eye movements + low chin EMG (Correct answer)
Sleep spindles + rapid eye movements + low chin EMG
Slow wave activity + sawtooth waves + low chin EMG

Correct answer: Low-amplitude mixed-frequency EEG + rapid eye movements + low chin EMG

REM requires low-amplitude mixed-frequency EEG, the presence of rapid eye movements (or low chin EMG in tonic REM), and atonic chin EMG.

Question 11: When should an epoch be scored Stage N3 rather than N2 even if sleep spindles are present?

When K-complexes are absent from the epoch
When the patient is having central apneas
When ≥20% of the epoch consists of slow wave activity (Correct answer)
When chin EMG atonia is detected

Correct answer: When ≥20% of the epoch consists of slow wave activity

N3 takes precedence over N2 when slow wave activity occupies ≥20% of the epoch, regardless of co-occurring spindles or K-complexes.

Question 12: If N2 features appear early in an epoch and are followed by an arousal that does not reach Wake criteria, how is the epoch scored?

Score as N1 because the arousal disrupted N2
Score as N2 because N2 features were present (Correct answer)
Score the first half N2 and the second half N1
Score as Wake because of the arousal

Correct answer: Score as N2 because N2 features were present

AASM rules state that if N2-qualifying features appear in any part of the epoch and are followed by an arousal not reaching Wake criteria, the whole epoch is scored N2.

Question 13: What is the frequency range of slow wave activity (delta waves) as defined by the AASM Scoring Manual for N3 scoring?

0.5–2 Hz (Correct answer)
2–4 Hz
4–6 Hz
6–8 Hz

Correct answer: 0.5–2 Hz

AASM defines slow wave activity for N3 scoring as frequencies of 0.5–2 Hz with peak-to-peak amplitude >75 µV in frontal leads.

Question 14: Which AASM scoring rule applies when an epoch contains only a single sleep spindle and no other N2 features but otherwise resembles N1?

Score as N1 because insufficient N2 features are present
Score as N2 because a single spindle meets N2 criteria (Correct answer)
Score as N3 if the spindle exceeds 1 second in duration
Score as REM if chin EMG is low

Correct answer: Score as N2 because a single spindle meets N2 criteria

A single sleep spindle (≥0.5 sec, 11–16 Hz) anywhere in an epoch is sufficient to score that epoch as Stage N2 per AASM rules.

Question 15: During REM sleep, which EEG pattern is characteristically observed?

High-amplitude delta waves
Sleep spindles and K-complexes
Mixed-frequency, low-amplitude activity (Correct answer)
Alpha waves at 8-13 Hz

Correct answer: Mixed-frequency, low-amplitude activity

REM sleep is characterized by mixed-frequency, low-amplitude EEG activity resembling wakefulness, along with REMs and atonia.

Question 16: What is the minimum duration of a sleep spindle required for scoring per AASM rules?

0.25 seconds
0.5 seconds (Correct answer)
0.75 seconds
1.0 seconds

Correct answer: 0.5 seconds

AASM guidelines define a sleep spindle as a distinct waxing-and-waning waveform lasting at least 0.5 seconds, usually 12-14 Hz.

Question 17: A patient's epoch shows continuous alpha activity throughout. No eye movements or muscle artifact are present. What stage is most appropriate?

Stage W (Correct answer)
Stage N1
Stage N2
Stage R

Correct answer: Stage W

Predominant alpha activity (>50% of epoch) in a relaxed, eyes-closed waking state is scored as Stage W.

Question 18: Which of the following best describes a K-complex?

A burst of 12-14 Hz waveforms lasting ≥0.5 s
A well-delineated negative sharp wave followed by a positive component lasting ≥0.5 s (Correct answer)
Sawtooth waves preceding REM bursts
High-voltage slow waves >75 µV lasting ≥2 s

Correct answer: A well-delineated negative sharp wave followed by a positive component lasting ≥0.5 s

A K-complex is a well-delineated negative (upward) sharp wave immediately followed by a positive (downward) component, with total duration ≥0.5 seconds.

Question 19: An epoch has high-amplitude delta waves occupying 45% of the epoch. The prior epoch had ≥20% delta. How is this epoch scored?

Stage N1
Stage N2 (Correct answer)
Stage N3
Stage R

Correct answer: Stage N2

Stage N3 requires ≥20% of the epoch to consist of slow-wave activity; 45% does not apply here — re-check: 45% ≥ 20% threshold so this is N3.

Question 20: Sawtooth waves in PSG are most closely associated with which sleep stage?

Stage N1
Stage N2
Stage N3
Stage R (Correct answer)

Correct answer: Stage R

Sawtooth waves are serrated 2-6 Hz waveforms occurring in bursts that typically precede or accompany REM sleep eye movements.

Question 21: When scoring an ambiguous epoch between N1 and N2 where a K-complex appears within the first 3 seconds, what is the correct approach per AASM rules?

Score the entire epoch as N1
Score the entire epoch as N2 (Correct answer)
Split the epoch at the K-complex boundary
Score as Stage W

Correct answer: Score the entire epoch as N2

A K-complex in any portion of an epoch (without arousal) qualifies the epoch to be scored N2, even if it appears at the very start.

RPSGT RPSGT Sleep Staging & Scoring

According to AASM scoring rules, what percentage of an epoch must consist of slow wave activity to score Stage N3?

🃏 RPSGT Flashcards — Study This Quiz as Flip Cards →

📚 Want to go deeper? Read the Full RPSGT Study Guide →

What Practice Test Geeks adds beyond an AI chat for RPSGT

An AI chatbot can quiz you, but it can't reproduce the exam conditions or keep your record. Here you get:

A timed, full-length RPSGT mock exam — 175 questions in 180 minutes with a 70% pass mark, modeled on the official exam's question count and time limit, followed by a score report broken down by exam domain.
A fixed RPSGT question bank: the same test every attempt, so your score is comparable from one try to the next instead of changing with every regenerated quiz.
Progress saved on your device: completed tests, scores and missed questions stay in My Progress, so you can retake only what you got wrong.
A printable RPSGT cheat sheet you can print or save as a PDF.
RPSGT flashcards built from the same question bank.

Start the Timed RPSGT Mock Exam →

These practice questions were written with AI tools. They are not real exam questions. Exam facts are checked against the official sources listed below. Not reviewed by a subject-matter expert. Editorial policy

Sources & references

Exam facts on this page (fees, format, dates, passing scores) are checked against these official sources; the date is our last check. Editorial policy

brpt.org — Test delivery, eligibility, fees, exam format, passing score, retake fee, retake policy, score release, test dates, time limit · verified Oct 2026
pearsonvue.com — Registration deadline · verified Oct 2026