Free DOH EEG / Neurodiagnostic Technologist mock test

EEG / Neurodiagnostic Technologist sample questions with answers

10 more original exam-style EEG / Neurodiagnostic Technologist questions, worked in full. They are not real or recalled exam questions, and none of them is in the mock above or on the bank page, so sit the mock first if you have not.

1. Question 1 · Abnormal EEG, Seizures and Epilepsy

   An infant with spasms has a chaotic, high-voltage, disorganized EEG with multifocal spikes. What is this pattern called?

   1. ABurst suppression
   2. BHypsarrhythmia
   3. CTriphasic waves
   4. DPeriodic lateralized epileptiform discharges
   Show answer and explanation

   Correct answer: B. Hypsarrhythmia

   Hypsarrhythmia is the chaotic high-amplitude background of infantile spasms (West syndrome). Burst suppression has alternating silence, triphasic waves are surface-positive blunt waves in metabolic disease and PLEDs are lateralized periodic.

   Reference: Ebersole JS, Pedley TA, Current Practice of Clinical Electroencephalography, 4th ed. (2014)

2. Question 2 · Abnormal EEG, Seizures and Epilepsy

   In a suspected case of electrocerebral inactivity, which technical change is recommended by the ACNS standard?

   1. AUse a notch filter alone and avoid all other filters
   2. BRecord only a 10-second sample at 7 microvolts per mm
   3. CUse sensitivity of at least 2 microvolts per mm, with interelectrode distances of at least 10 cm and a 30-minute recording
   4. DUse only the standard 10-20 bipolar chain at default settings
   Show answer and explanation

   Correct answer: C. Use sensitivity of at least 2 microvolts per mm, with interelectrode distances of at least 10 cm and a 30-minute recording

   The cerebral death protocol requires high sensitivity (2 uV/mm), long interelectrode distances and at least 30 minutes of recording, with integrity checks. Default routine settings or a short sample are inadequate.

   Reference: American Clinical Neurophysiology Society, Guideline 3: Minimum Technical Standards for EEG Recording in Suspected Cerebral Death (2016)

3. Question 3 · EEG Instrumentation and Recording Technique

   What does a longer time constant on the low-frequency filter do to slow activity such as delta waves?

   1. AIt removes more slow activity from the record, because the low-frequency cutoff rises as the time constant lengthens
   2. BIt has no effect on delta activity, which is determined only by the setting of the high-frequency filter
   3. CIt converts slow waves into spike-like transients by differentiating the signal at the input stage
   4. DIt passes more slow activity, because the low-frequency filter cutoff falls
   Show answer and explanation

   Correct answer: D. It passes more slow activity, because the low-frequency filter cutoff falls

   The low-frequency cutoff is roughly 1/(2 pi x TC), so a longer time constant gives a lower cutoff and passes slower activity. A shorter one attenuates delta and slow drift. Delta is governed by the low filter, and filters do not create spikes.

   Reference: Ebersole JS, Pedley TA, Current Practice of Clinical Electroencephalography, 4th ed. (2014)

4. Question 4 · EEG Instrumentation and Recording Technique

   Which standard recording settings are typical for a routine adult EEG display?

   1. APaper speed 5 mm per second, sensitivity 100 microvolts per mm
   2. BPaper speed 30 mm per second, sensitivity 7 microvolts per mm
   3. CPaper speed 60 mm per second, sensitivity 70 microvolts per mm
   4. DPaper speed 15 mm per second, sensitivity 1 microvolt per mm
   Show answer and explanation

   Correct answer: B. Paper speed 30 mm per second, sensitivity 7 microvolts per mm

   A 30 mm/s speed and 7 uV/mm sensitivity are the usual adult routine display settings. The other combinations would compress the trace, hide cerebral activity or exaggerate it.

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

5. Question 5 · EEG Instrumentation and Recording Technique

   On a referential montage using an ear reference, every channel shows the same sharp waveform at the same moment, with no field. Which source is most likely?

   1. AActivity at the reference electrode, so change the reference or montage
   2. BPoorly prepared skin at the occipital electrodes, so clean the sites again
   3. CA true generalised seizure discharge with a wide field
   4. DNormal alpha activity spreading to the other channels from the back
   Show answer and explanation

   Correct answer: A. Activity at the reference electrode, so change the reference or montage

   A waveform that appears in every channel referenced to the same electrode points to contamination of the reference, such as ECG or temporal activity at the ear electrode. Switching to a different reference or a bipolar montage will confirm this. A true generalised discharge would vary between channels, and poor skin prep affects individual channels.

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

6. Question 6 · Normal EEG and Artifacts

   At what age does the posterior dominant rhythm in a waking child normally reach about 8 Hz?

   1. AAbout ten years of age
   2. BAt birth
   3. CAbout three years of age
   4. DAbout one year of age
   Show answer and explanation

   Correct answer: C. About three years of age

   The posterior dominant rhythm develops with age, starting near 4 Hz in infancy and reaching about 8 Hz by around three years. A slower rhythm than expected at that age should be reported for interpretation.

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

7. Question 7 · Abnormal EEG, Seizures and Epilepsy

   Why is sleep deprivation sometimes requested before a diagnostic EEG?

   1. AIt guarantees that a seizure will occur during recording
   2. BIt increases the chance of recording epileptiform discharges
   3. CIt removes muscle artifact from the recording
   4. DIt lowers electrode impedance at the scalp sites after skin preparation
   Show answer and explanation

   Correct answer: B. It increases the chance of recording epileptiform discharges

   Sleep deprivation and recording of sleep raise the yield of interictal epileptiform discharges in many patients with epilepsy. It does not guarantee a seizure, reduce artifact or change electrode impedance.

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

8. Question 8 · Evoked Potentials, Nerve Conduction and EMG

   On needle EMG performed by the physician, a muscle shows small, short-duration, polyphasic motor unit potentials with early recruitment. Which condition do these findings suggest?

   1. AChronic reinnervation after nerve injury
   2. BA primary muscle disorder, such as a myopathy
   3. CUpper motor neuron weakness from a stroke
   4. DA neuromuscular junction disorder such as botulism
   Show answer and explanation

   Correct answer: B. A primary muscle disorder, such as a myopathy

   Small, short, polyphasic units with early recruitment reflect loss of muscle fibres within each motor unit, typical of myopathy. Chronic reinnervation produces large, long units with reduced recruitment, and stroke gives normal units with reduced activation.

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

9. Question 9 · Patient Care, Infection Control and Safety

   A patient scheduled for a physician-performed needle EMG takes warfarin and has an INR of 3.5. What should the technologist do?

   1. AInform the supervising physician before starting, as the INR is raised
   2. BProceed as planned, because EMG needles are too fine to cause bleeding
   3. CTell the patient to stop the warfarin and return after a week
   4. DSample deep muscles first, to reduce the number of insertions
   Show answer and explanation

   Correct answer: A. Inform the supervising physician before starting, as the INR is raised

   Needle EMG carries a small bleeding risk, so anticoagulation with a high INR must be reported to the supervising physician, who decides whether and how to proceed. Needles are not too fine to bleed, and stopping warfarin is a prescriber decision that the technologist must not make. Sampling deep muscles first does not lower the risk.

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

10. Question 10 · Professional Practice and Ethics

    A technologist wants to email an EEG file to a colleague's personal account for a second opinion. What is the correct response?

    1. APost it to a public file-sharing site and send the colleague the link
    2. BSend it, as the patient's name has been removed from the subject line
    3. CSend it if the colleague promises to delete it after reading the report
    4. DDecline, and use only the facility's approved secure sharing system
    Show answer and explanation

    Correct answer: D. Decline, and use only the facility's approved secure sharing system

    UAE Federal Law No. 2 of 2019 requires confidentiality and secure handling of health information, so sharing must use approved systems. A removed subject line, a promise to delete or a public link do not protect the data.

    Reference: UAE Federal Law No. 2 of 2019 on the Use of Information and Communications Technology in Health Fields