DOH EEG / Neurodiagnostic Technologist exam questions

The EEG / Neurodiagnostic Technologist exam in every GCC country

From each regulator's own exam pages; anything a regulator does not publish says so. Assessment mode also depends on your licence title, so confirm your route on your eligibility notice.

12 worked EEG / Neurodiagnostic Technologist practice questions

Original exam-style questions from the bank, spread across the blueprint domains. They are not real or recalled exam questions. Try each one, then open the answer for the rationale and reference. None of them appear in the free mock exam, so reading them will not spoil it.

1. Question 1 · Abnormal EEG, Seizures and Epilepsy

   A confused febrile patient has repeated periodic spike discharges every 1 to 2 seconds over the left temporal region. Which condition should the technologist alert the physician about as a possibility?

   1. AHerpes simplex encephalitis
   2. BAbsence epilepsy, which gives generalized 3 Hz spike-and-wave rather than periodic discharges
   3. CBenign rolandic epilepsy, which shows centrotemporal spikes in a well child
   4. DNarcolepsy, which is a sleep disorder and not an infection of the brain
   Show answer and explanation

   Correct answer: A. Herpes simplex encephalitis

   Periodic lateralized discharges over a temporal region in a febrile confused patient raise herpes simplex encephalitis, which is urgent. Absence and rolandic epilepsy have different patterns, and narcolepsy is a sleep disorder.

   Reference: Tatum WO, Handbook of EEG Interpretation, 3rd ed. (2021)

2. Question 2 · EEG Instrumentation and Recording Technique

   In the International 10-20 system, which electrode is placed at the vertex of the head?

   1. AFz
   2. BPz
   3. COz
   4. DCz
   Show answer and explanation

   Correct answer: D. Cz

   Cz sits midway between nasion and inion and midway between the preauricular points. Fz and Pz are frontal and parietal midline points, and Oz is occipital.

   Reference: American Clinical Neurophysiology Society, Guideline 1: Minimum Technical Requirements for Performing Clinical Electroencephalography (2016)

3. Question 3 · EEG Instrumentation and Recording Technique

   In the 10-20 system, what do odd and even electrode numbers indicate?

   1. AOdd numbers are on the left and even numbers on the right
   2. BOdd numbers are on the right and even numbers on the left
   3. COdd numbers are anterior and even numbers posterior
   4. DOdd numbers are ground and even numbers reference
   Show answer and explanation

   Correct answer: A. Odd numbers are on the left and even numbers on the right

   Odd numbers label left hemisphere sites and even numbers right hemisphere sites, with z for the midline. The other options do not describe the convention.

   Reference: American Clinical Neurophysiology Society, Guideline 1: Minimum Technical Requirements for Performing Clinical Electroencephalography (2016)

4. Question 4 · EEG Instrumentation and Recording Technique

   A technologist uses a bipolar longitudinal montage. A negative-going waveform appears at the same moment in two channels that share an electrode, one pointing up and the other down. What does this phase reversal indicate?

   1. AThe shared electrode has failed and should be replaced
   2. BThe two channels have opposite gain settings
   3. CThe field maximum lies at the shared electrode
   4. DThe activity is artifact from the ground electrode
   Show answer and explanation

   Correct answer: C. The field maximum lies at the shared electrode

   In a bipolar chain, opposing deflections in adjacent channels that share an electrode localize the maximum of the potential at that shared electrode. Failure and gain faults do not produce a reproducible phase reversal, and ground artifact appears in all channels.

   Reference: American Clinical Neurophysiology Society, Guideline 6: A Proposal for Standard Montages to Be Used in Clinical EEG (2016)

5. Question 5 · Evoked Potentials, Nerve Conduction and EMG

   On median somatosensory evoked potentials, which peak reflects the primary somatosensory cortex response and is commonly used as the cortical landmark?

   1. AP100
   2. BN20
   3. CWave V
   4. DF wave
   Show answer and explanation

   Correct answer: B. N20

   The N20 is the primary cortical median SSEP response. P100 is the pattern-reversal VEP, wave V is a BAEP component and F wave is a late motor response.

   Reference: American Clinical Neurophysiology Society, Guideline 9: Guidelines on Evoked Potentials (2016)

6. Question 6 · Evoked Potentials, Nerve Conduction and EMG

   Repetitive nerve stimulation at 3 Hz shows a 25 percent decrement in the compound muscle action potential amplitude between the first and fourth responses. Which disorder does this support?

   1. AA neuromuscular junction disorder such as myasthenia gravis
   2. BCharcot-Marie-Tooth disease type 1, which shows uniform slowing of conduction velocity
   3. CNormal variation that requires no further testing and no clinical comment
   4. DCarpal tunnel syndrome, which affects median conduction across the wrist only
   Show answer and explanation

   Correct answer: A. A neuromuscular junction disorder such as myasthenia gravis

   A decrement above about 10 percent with low-rate stimulation suggests a postsynaptic junction disorder. CMT shows slowed velocities, and carpal tunnel affects median conduction across the wrist, not RNS decrement.

   Reference: Preston DC, Shapiro BE, Electromyography and Neuromuscular Disorders, 4th ed. (2021)

7. Question 7 · Neuroanatomy and Neurophysiology

   Electrodes C3 and C4 are placed over which part of the cortex?

   1. AThe inferior frontal lobes just above the eyebrows
   2. BThe occipital poles behind the lambdoid suture, overlying the visual cortex areas
   3. CThe region around the central sulcus, over the pre- and postcentral gyri
   4. DThe anterior temporal lobes in front of the ears
   Show answer and explanation

   Correct answer: C. The region around the central sulcus, over the pre- and postcentral gyri

   C3 and C4 overlie the central region, covering the precentral motor gyrus and the postcentral sensory gyrus, which is why the mu rhythm is seen here. Occipital electrodes are O1 and O2, frontal poles are Fp1 and Fp2, and anterior temporal are F7 and F8.

   Reference: American Clinical Neurophysiology Society, Guideline 5: Guidelines for Standard Electrode Position Nomenclature (2016)

8. Question 8 · EEG Instrumentation and Recording Technique

   Why does a differential amplifier reduce 50 Hz mains interference in an EEG?

   1. AIt removes frequencies above 50 Hz from the trace
   2. BIt cancels signals that are in phase at both input electrodes
   3. CIt records the voltage under the reference electrode in each channel
   4. DIt amplifies signals that are common to both electrodes
   Show answer and explanation

   Correct answer: B. It cancels signals that are in phase at both input electrodes

   A differential amplifier amplifies the difference between its two inputs, so in-phase interference that reaches both electrodes equally is cancelled, which is common-mode rejection. It does not amplify common signals, use one electrode alone, or act as a low-pass filter.

   Reference: Tatum WO, Handbook of EEG Interpretation, 3rd edition (2021)

9. Question 9 · Normal EEG and Artifacts

   Which waveform is characteristic of REM sleep on the EEG?

   1. ALow-voltage mixed-frequency activity with sawtooth waves
   2. BHigh-amplitude delta waves over the frontal regions
   3. CSleep spindles and K-complexes
   4. DVertex waves and positive occipital sharp transients of sleep
   Show answer and explanation

   Correct answer: A. Low-voltage mixed-frequency activity with sawtooth waves

   REM sleep shows low-voltage mixed-frequency activity, rapid eye movements and sawtooth waves, with reduced chin tone. Spindles and K-complexes mark N2, delta is typical of N3, and vertex waves are seen in N1 and N2.

   Reference: Troester MM et al., The AASM Manual for the Scoring of Sleep and Associated Events, version 3 (2023)

10. Question 10 · Abnormal EEG, Seizures and Epilepsy

    During a routine EEG, a patient is unresponsive and shows continuous generalised spike-and-wave discharges with no visible movements for several minutes. What should the technologist do?

    1. AStop recording and let the patient wake spontaneously
    2. BRemove the electrodes before moving the patient
    3. CContinue the study and report the result later in the day
    4. DAlert the physician urgently and document, as this may be nonconvulsive status epilepticus
    Show answer and explanation

    Correct answer: D. Alert the physician urgently and document, as this may be nonconvulsive status epilepticus

    Continuous epileptiform discharges with impaired consciousness may represent nonconvulsive status epilepticus, a medical emergency that needs urgent physician review. Continuing routinely or removing electrodes delays treatment, and stopping the recording loses key evidence.

    Reference: Trinka E et al., A definition and classification of status epilepticus, Epilepsia (2015)

11. Question 11 · Evoked Potentials, Nerve Conduction and EMG

    Which nerve conduction finding supports carpal tunnel syndrome?

    1. AProlonged median distal latency across the wrist with normal ulnar studies
    2. BAbsent sural sensory response with normal median studies
    3. CSlowed ulnar conduction across the elbow
    4. DNormal median latency with a reduced F-wave in the legs
    Show answer and explanation

    Correct answer: A. Prolonged median distal latency across the wrist with normal ulnar studies

    Compression of the median nerve at the wrist slows conduction across the carpal tunnel, prolonging distal sensory and motor latencies while the ulnar studies remain normal. The other findings point to ulnar neuropathy at the elbow or lower-limb problems.

    Reference: Preston DC, Shapiro BE, Electromyography and Neuromuscular Disorders, 4th edition (2020)

12. Question 12 · Patient Care, Infection Control and Safety

    A patient with diabetes is scheduled for an EEG. What preparation advice is correct?

    1. ASkip the insulin dose on the morning of the test to avoid a low glucose
    2. BFast for 12 hours before the appointment
    3. CEat normally and take usual medication unless advised otherwise
    4. DDrink strong coffee on the morning of the test to stay alert
    Show answer and explanation

    Correct answer: C. Eat normally and take usual medication unless advised otherwise

    Low blood glucose can alter the EEG and endanger the patient, so patients should eat normally and keep usual medicines unless instructed. Fasting or skipping insulin risks hypoglycaemia or hyperglycaemia.

    Reference: American Clinical Neurophysiology Society, Guideline 1: Minimum Technical Requirements for Performing Clinical Electroencephalography (2016)

EEG / Neurodiagnostic Technologist reference books and guidelines

Every question in this bank names the textbook or guideline its answer rests on. These are the sources our EEG / Neurodiagnostic Technologist questions cite most often - the reading list to revise from alongside the bank.

Where your regulator publishes a reading list, use the editions it names. Exam questions are not taken from any one book.