P O LY S O M N O G R A P H Y · S L E E P T E C H N O L O G Y · B R P T
Ground Loop — Practice
Question Bank
Comprehensive Review with Questions, Answers & Rationales
Topics: PSG Fundamentals · Scoring · Titration · Sleep Disorders · Equipment ·
& More
Edition 1 · August 2026
,Table of Contents
1. Instructions for Use 2
2. PSG Fundamentals & Signal Acquisition 2
3. Scoring & Sleep Stage Classification 3
4. PAP Titration & Therapy 4
5. Sleep Disorders & Clinical Practice 5
Ground Loop · Polysomnography Page 1
,GROUND LOOP PRACTICE GUIDE PSG FUNDAMENTALS
How to Use This Guide
Read each stem, choose your answer, then check the rationale directly below it. The correct option is marked, and each
wrong option is explained so you understand why it's wrong — not just that it is.
PSG Fundamentals & Signal Acquisition
1 What is a ground loop?
A Undesirable electrical pathway between 2 separate ground connections, resulting in a possible hazard to the
patient
B A type of electrode placement
C A calibration technique
D A filter setting
Why A is correct: A ground loop is an undesirable electrical pathway between two separate ground connections, which
can result in a possible hazard to the patient.
B — This is not a ground loop.
C — This is not a ground loop.
D — This is not a ground loop.
2 A single page of a PSG, typically representing 30 seconds of data, is called a(n):
A Montage
B Epoch
C Derivation
D Channel
Why B is correct: An epoch is a single page of a PSG, typically representing 30 seconds of data.
A — A montage is the electrode arrangement.
C — A derivation is a signal from electrode pairs.
D — A channel is a single signal path.
, 3 What is the normal arterial pO2 value?
A 60-70 mmHg
B 70-80 mmHg
C 80-100 mmHg
D 100-120 mmHg
Why C is correct: Normal arterial pO2 is 80-100 mmHg.
A — This is below normal.
B — This is below normal.
D — This is above normal.
4 Which class of drugs is known to aggravate Periodic Limb Movements of sleep?
A SSRIs
B Tricyclic Antidepressants
C Benzodiazepines
D Antihistamines
Why B is correct: Tricyclic antidepressants are known to aggravate Periodic Limb Movements of sleep.
A — SSRIs may also affect PLMs but TCAs are more commonly associated.
C — Benzodiazepines may reduce PLMs.
D — Antihistamines are not primarily associated.
5 What considerations should be given to the choice of electrodes used for recording EEG?
A Choose a material that has minimum drift of electrode potential and a very long time constant
B Choose the largest electrode available
C Choose electrodes with the highest impedance
D Choose electrodes that are reusable
Why A is correct: Electrodes should have minimum drift of electrode potential and a very long time constant for stable
EEG recording.
B — Size is not the primary consideration.
C — Low impedance is preferred.
D — Reusability is not the primary consideration.
Ground Loop — Practice
Question Bank
Comprehensive Review with Questions, Answers & Rationales
Topics: PSG Fundamentals · Scoring · Titration · Sleep Disorders · Equipment ·
& More
Edition 1 · August 2026
,Table of Contents
1. Instructions for Use 2
2. PSG Fundamentals & Signal Acquisition 2
3. Scoring & Sleep Stage Classification 3
4. PAP Titration & Therapy 4
5. Sleep Disorders & Clinical Practice 5
Ground Loop · Polysomnography Page 1
,GROUND LOOP PRACTICE GUIDE PSG FUNDAMENTALS
How to Use This Guide
Read each stem, choose your answer, then check the rationale directly below it. The correct option is marked, and each
wrong option is explained so you understand why it's wrong — not just that it is.
PSG Fundamentals & Signal Acquisition
1 What is a ground loop?
A Undesirable electrical pathway between 2 separate ground connections, resulting in a possible hazard to the
patient
B A type of electrode placement
C A calibration technique
D A filter setting
Why A is correct: A ground loop is an undesirable electrical pathway between two separate ground connections, which
can result in a possible hazard to the patient.
B — This is not a ground loop.
C — This is not a ground loop.
D — This is not a ground loop.
2 A single page of a PSG, typically representing 30 seconds of data, is called a(n):
A Montage
B Epoch
C Derivation
D Channel
Why B is correct: An epoch is a single page of a PSG, typically representing 30 seconds of data.
A — A montage is the electrode arrangement.
C — A derivation is a signal from electrode pairs.
D — A channel is a single signal path.
, 3 What is the normal arterial pO2 value?
A 60-70 mmHg
B 70-80 mmHg
C 80-100 mmHg
D 100-120 mmHg
Why C is correct: Normal arterial pO2 is 80-100 mmHg.
A — This is below normal.
B — This is below normal.
D — This is above normal.
4 Which class of drugs is known to aggravate Periodic Limb Movements of sleep?
A SSRIs
B Tricyclic Antidepressants
C Benzodiazepines
D Antihistamines
Why B is correct: Tricyclic antidepressants are known to aggravate Periodic Limb Movements of sleep.
A — SSRIs may also affect PLMs but TCAs are more commonly associated.
C — Benzodiazepines may reduce PLMs.
D — Antihistamines are not primarily associated.
5 What considerations should be given to the choice of electrodes used for recording EEG?
A Choose a material that has minimum drift of electrode potential and a very long time constant
B Choose the largest electrode available
C Choose electrodes with the highest impedance
D Choose electrodes that are reusable
Why A is correct: Electrodes should have minimum drift of electrode potential and a very long time constant for stable
EEG recording.
B — Size is not the primary consideration.
C — Low impedance is preferred.
D — Reusability is not the primary consideration.
