NBRC SDS CERTIFICATION EXAM 2026-2027 –
ULTIMATE TEST BANK | 400 REAL EXAM
QUESTIONS WITH DETAILED CORRECT ANSWERS
(VERIFIED) | GRADED A+ | COMPLETE FINAL EXAM
REVIEW (BRAND NEW!)
1. What is the primary function of the NREM sleep stage N3?
a. Dream consolidation
b. Memory encoding
c. Physical restoration and slow-wave activity
d. Muscle atonia maintenance
Correct Answer: c
Explanation: N3 (slow-wave sleep) is associated with physical restoration, growth
hormone release, and slow-wave EEG activity.
2. Which EEG waveform is most characteristic of stage N2 sleep?
a. Delta waves
b. Alpha rhythm
c. Sleep spindles and K-complexes
d. Sawtooth waves
Correct Answer: c
Explanation: N2 is defined by the presence of sleep spindles and K-complexes on
EEG.
,3. What is the minimum duration of an apnea event for scoring in adult
polysomnography?
a. 5 seconds
b. 10 seconds
c. 15 seconds
d. 20 seconds
Correct Answer: b
Explanation: AASM scoring rules require a ≥90% drop in airflow for ≥10 seconds.
4. Which of the following defines a hypopnea according to AASM recommended
criteria?
a. ≥30% drop in airflow for ≥10 seconds with ≥3% desaturation or arousal
b. ≥50% drop in airflow for ≥10 seconds with ≥4% desaturation
c. ≥70% drop in airflow for ≥5 seconds with any desaturation
d. Complete cessation of airflow for ≥10 seconds
Correct Answer: a
Explanation: AASM recommends ≥30% reduction in nasal pressure for ≥10
seconds with ≥3% desaturation or an arousal.
5. What is the normal apnea-hypopnea index (AHI) in adults?
a. <1 event/hour
b. <5 events/hour
c. <10 events/hour
d. <15 events/hour
Correct Answer: b
,Explanation: AHI <5 is considered normal in adults.
6. Which of the following is a central apnea event?
a. Absence of airflow with continued respiratory effort
b. Absence of airflow and absence of respiratory effort
c. Partial airflow with paradoxical breathing
d. Absence of airflow with snoring
Correct Answer: b
Explanation: Central apnea shows no airflow and no respiratory effort (no
chest/abdominal movement).
7. What is the recommended electrode placement for the reference EEG in a
standard PSG?
a. C4-M1
b. F3-M2
c. O1-M2
d. All of the above
Correct Answer: d
Explanation: AASM recommends at least F4-M1, C4-M1, and O2-M1 with
contralateral references.
8. What is the typical frequency range for delta waves?
a. 0.5-2 Hz
b. 4-7 Hz
c. 8-12 Hz
, d. 13-30 Hz
Correct Answer: a
Explanation: Delta waves are 0.5-2 Hz, seen in N3 sleep.
9. Which sleep stage shows sawtooth waves on EEG?
a. N1
b. N2
c. N3
d. REM
Correct Answer: d
Explanation: Sawtooth waves are characteristic of REM sleep, often preceding
rapid eye movements.
10. What is the definition of REM sleep without atonia?
a. Persistence of chin EMG tone during REM
b. Complete loss of chin tone
c. Increased limb movements
d. Reduced eye movements
Correct Answer: a
Explanation: REM sleep without atonia is chin EMG tone >0 during REM, seen in
REM behavior disorder.
11. What is the scoring rule for a respiratory effort-related arousal (RERA)?
a. ≥50% drop in airflow for 10 sec with arousal
b. ≤30% drop in airflow for 10 sec with ≥3% desaturation
ULTIMATE TEST BANK | 400 REAL EXAM
QUESTIONS WITH DETAILED CORRECT ANSWERS
(VERIFIED) | GRADED A+ | COMPLETE FINAL EXAM
REVIEW (BRAND NEW!)
1. What is the primary function of the NREM sleep stage N3?
a. Dream consolidation
b. Memory encoding
c. Physical restoration and slow-wave activity
d. Muscle atonia maintenance
Correct Answer: c
Explanation: N3 (slow-wave sleep) is associated with physical restoration, growth
hormone release, and slow-wave EEG activity.
2. Which EEG waveform is most characteristic of stage N2 sleep?
a. Delta waves
b. Alpha rhythm
c. Sleep spindles and K-complexes
d. Sawtooth waves
Correct Answer: c
Explanation: N2 is defined by the presence of sleep spindles and K-complexes on
EEG.
,3. What is the minimum duration of an apnea event for scoring in adult
polysomnography?
a. 5 seconds
b. 10 seconds
c. 15 seconds
d. 20 seconds
Correct Answer: b
Explanation: AASM scoring rules require a ≥90% drop in airflow for ≥10 seconds.
4. Which of the following defines a hypopnea according to AASM recommended
criteria?
a. ≥30% drop in airflow for ≥10 seconds with ≥3% desaturation or arousal
b. ≥50% drop in airflow for ≥10 seconds with ≥4% desaturation
c. ≥70% drop in airflow for ≥5 seconds with any desaturation
d. Complete cessation of airflow for ≥10 seconds
Correct Answer: a
Explanation: AASM recommends ≥30% reduction in nasal pressure for ≥10
seconds with ≥3% desaturation or an arousal.
5. What is the normal apnea-hypopnea index (AHI) in adults?
a. <1 event/hour
b. <5 events/hour
c. <10 events/hour
d. <15 events/hour
Correct Answer: b
,Explanation: AHI <5 is considered normal in adults.
6. Which of the following is a central apnea event?
a. Absence of airflow with continued respiratory effort
b. Absence of airflow and absence of respiratory effort
c. Partial airflow with paradoxical breathing
d. Absence of airflow with snoring
Correct Answer: b
Explanation: Central apnea shows no airflow and no respiratory effort (no
chest/abdominal movement).
7. What is the recommended electrode placement for the reference EEG in a
standard PSG?
a. C4-M1
b. F3-M2
c. O1-M2
d. All of the above
Correct Answer: d
Explanation: AASM recommends at least F4-M1, C4-M1, and O2-M1 with
contralateral references.
8. What is the typical frequency range for delta waves?
a. 0.5-2 Hz
b. 4-7 Hz
c. 8-12 Hz
, d. 13-30 Hz
Correct Answer: a
Explanation: Delta waves are 0.5-2 Hz, seen in N3 sleep.
9. Which sleep stage shows sawtooth waves on EEG?
a. N1
b. N2
c. N3
d. REM
Correct Answer: d
Explanation: Sawtooth waves are characteristic of REM sleep, often preceding
rapid eye movements.
10. What is the definition of REM sleep without atonia?
a. Persistence of chin EMG tone during REM
b. Complete loss of chin tone
c. Increased limb movements
d. Reduced eye movements
Correct Answer: a
Explanation: REM sleep without atonia is chin EMG tone >0 during REM, seen in
REM behavior disorder.
11. What is the scoring rule for a respiratory effort-related arousal (RERA)?
a. ≥50% drop in airflow for 10 sec with arousal
b. ≤30% drop in airflow for 10 sec with ≥3% desaturation
