100+ Free CMEG Practice Questions

Pass your ABRET Certified Magnetoencephalography Technologist exam on the first try — instant access, no signup required.

✓ No registration✓ No credit card✓ No hidden fees✓ Start practicing immediately

Not publicly reported Pass Rate

100+ Questions

100% Free

1 / 10

Question 1

Score: 0/0

A patient scheduled for an MEG study has been instructed to avoid caffeine on the morning of the exam. What is the primary reason for this instruction?

Caffeine interferes with the SQUID sensor calibration

Caffeine creates a magnetic field that disrupts the MEG signal

Caffeine causes the helium to evaporate more quickly

Caffeine can increase muscle artifact and alter baseline brain activity

to track

2026 Statistics

Key Facts: CMEG Exam

4 hrs

Exam Time

ABRET CMEG Handbook

$400

Exam Fee

ABRET fee schedule (2026)

40%

Instrumentation Domain

ABRET CMEG content outline (heaviest)

5 yrs

Credential Validity

ABRET recertification policy

Required Cases

25 evoked + 50 spontaneous

15 CEs

Renewal Requirement

ABRET recertification

The ABRET CMEG exam is a computer-based multiple-choice exam with a 4-hour time limit and $400 fee. Content weighting: MEG Instrumentation (40%), Performing the Study (30%), Post-Study Procedures (20%), Pre-Study Preparation (10%). The exam follows completion of ASET's 12-module MEG course. Candidates must hold R.EEG.T. or R.EP.T., have 6+ months supervised MEG experience, and document 25 evoked + 50 spontaneous cases. Certification valid for 5 years with 15 CE hours for renewal.

Sample CMEG Practice Questions

Try these sample questions to test your CMEG exam readiness. Each question includes a detailed explanation. Start the interactive quiz above for the full 100+ question experience with AI tutoring.

1A patient scheduled for an MEG study has been instructed to avoid caffeine on the morning of the exam. What is the primary reason for this instruction?

A.Caffeine interferes with the SQUID sensor calibration

B.Caffeine creates a magnetic field that disrupts the MEG signal

C.Caffeine causes the helium to evaporate more quickly

D.Caffeine can increase muscle artifact and alter baseline brain activity

Explanation: Caffeine is a central nervous system stimulant that can increase muscle tension (leading to more myogenic artifact) and alter baseline neural activity patterns. These changes can compromise the quality of MEG recordings by introducing unwanted signals and changing the brain's resting state. Caffeine does not directly affect SQUID sensors, helium evaporation, or generate magnetic fields.

2Before performing an MEG study, the technologist reviews the patient's medical history and discovers the patient has a vagus nerve stimulator (VNS). What is the most appropriate action?

A.Cancel the study immediately as VNS is an absolute contraindication

B.Proceed normally since VNS devices are non-magnetic

C.Consult with the referring physician about temporarily turning off the VNS during the recording

D.Increase the SQUID sensitivity to compensate for VNS interference

Explanation: A vagus nerve stimulator produces electrical pulses that generate magnetic artifact in MEG recordings. The standard approach is to consult with the referring physician about temporarily disabling the device during the MEG study to minimize artifact. VNS is not an absolute contraindication to MEG, but its periodic stimulation cycles will produce significant artifact if left active.

3Which three anatomical landmarks are used as fiducial points for MEG head digitization?

A.Nasion, inion, and vertex (Cz)

B.Nasion, left preauricular point, and right preauricular point

C.Left mastoid, right mastoid, and nasion

D.Fp1, Fp2, and Oz positions

Explanation: The standard fiducial points for MEG head digitization are the nasion (bridge of the nose between the eyes) and the left and right preauricular points (just anterior to the tragus of each ear). These three points define a coordinate system that allows coregistration of the MEG data with the patient's MRI scan. They are chosen because they are easily identifiable and reproducible across sessions.

4What is the recommended scalp electrode impedance level for EEG electrodes applied simultaneously during an MEG study?

A.Below 1 kΩ

B.Below 20 kΩ

C.Below 5 kΩ

D.Impedance is irrelevant for MEG recordings

Explanation: When EEG electrodes are applied for simultaneous EEG-MEG recording, electrode impedances should be kept below 5 kΩ, consistent with standard clinical EEG practice. Good impedance ensures high-quality EEG data that complements the MEG recording. Low impedance reduces noise and artifact in the EEG channels, which is especially important when correlating EEG and MEG findings.

5A patient presents for an MEG study with a history of medically refractory epilepsy. Which lobe is most commonly the source of epileptiform discharges evaluated by MEG for surgical planning?

A.Frontal lobe

B.Parietal lobe

C.Temporal lobe

D.Occipital lobe

Explanation: Temporal lobe epilepsy is the most common form of focal epilepsy referred for presurgical evaluation, and MEG plays a key role in localizing epileptiform activity. MEG is particularly valuable for temporal lobe sources because many temporal cortical generators produce tangential currents in the sylvian fissure that are well-detected by MEG sensors. This makes MEG an important tool in surgical planning for temporal lobectomy candidates.

6During patient preparation for an MEG study, the technologist discovers the patient is wearing an underwire bra. What should the technologist do?

A.Proceed with the study since the bra is far from the head

B.Ask the patient to remove the bra or change into a hospital gown

C.Demagnetize the bra using a degaussing coil

D.Apply additional shielding around the patient's torso

Explanation: Ferromagnetic materials anywhere on the patient's body can produce magnetic artifact that contaminates MEG recordings. Underwire bras typically contain steel, which is ferromagnetic. The standard practice is to have the patient remove all ferromagnetic items, including underwire bras, jewelry, hair clips, and belt buckles, and change into artifact-free clothing or a hospital gown before entering the magnetically shielded room.

7Which neuroanatomical structure generates the primary currents detected by MEG?

A.White matter tracts

B.Pyramidal neurons in cortical sulci

C.Deep subcortical nuclei such as the thalamus

D.Cerebellar Purkinje cells

Explanation: MEG primarily detects the magnetic fields produced by intracellular currents flowing in the apical dendrites of pyramidal neurons. These neurons are oriented perpendicular to the cortical surface, and when located in sulci, their currents flow tangentially to the scalp surface. Tangential currents produce magnetic fields that exit and re-enter the skull, making them detectable by MEG sensors positioned outside the head.

8Standard infection prevention for MEG head position indicator (HPI) coils between patients includes:

A.Autoclaving the coils at 134°C

B.Replacing the coils after each patient

C.Soaking in a glutaraldehyde solution for 20 minutes

D.Cleaning with an approved disinfectant wipe

Explanation: HPI coils are reusable devices that contact intact skin and are classified as non-critical items according to the Spaulding classification. Standard infection prevention requires cleaning with an approved low-level or intermediate-level disinfectant wipe between patients. Autoclaving and chemical sterilization are not appropriate for these electronic components, and replacing them after each use would be impractical and wasteful.

9During head digitization for MEG, additional scalp points beyond the fiducial landmarks are collected. What is the primary purpose of these extra points?

A.To determine the patient's head circumference for helmet sizing

B.To create a map for EEG electrode placement

C.To calibrate the SQUID sensors for the individual patient

D.To improve the accuracy of MEG-to-MRI coregistration

Explanation: Additional scalp surface points (typically 100-500+) are digitized to create a detailed representation of the patient's head shape. These points are then matched to the patient's MRI scalp surface using algorithms such as iterative closest point (ICP), significantly improving the accuracy of MEG-to-MRI coregistration beyond what the three fiducial points alone can provide. More points generally yield better coregistration accuracy.

10A patient scheduled for MEG has a programmable ventriculoperitoneal (VP) shunt with an adjustable magnetic valve. What is the primary concern?

A.The magnetic environment near the MEG system could alter the shunt valve setting

B.The VP shunt will generate large magnetic artifacts in the MEG recording

C.The helium cooling system may cause the shunt to malfunction

D.The VP shunt makes MEG coregistration impossible

Explanation: Programmable VP shunt valves use magnets to set the pressure at which cerebrospinal fluid drains. Exposure to strong magnetic fields, such as those near the MEG dewar or within the magnetically shielded room, can inadvertently change the valve setting, potentially causing dangerous over- or under-drainage of CSF. The referring physician and neurosurgeon should be consulted, and the valve setting should be verified after the procedure.

About the CMEG Exam

The CMEG credential from ABRET certifies expertise in magnetoencephalography technology. The exam covers MEG instrumentation including SQUID sensors, helium management, and magnetically shielded rooms (40%), performing MEG studies including evoked field protocols (AEF, SEF, VEF, LEF, MEF) and epilepsy localization (30%), post-study procedures including MRI coregistration and source localization (20%), and pre-study patient preparation (10%). Candidates must hold an R.EEG.T. or R.EP.T. credential and have supervised MEG experience.

Questions

Multiple-choice (count not publicly disclosed) scored questions

Time Limit

4 hours

Passing Score

Criterion-referenced (board-determined minimum competency)

Exam Fee

$400 (ABRET)

CMEG Exam Content Outline

40%

MEG Instrumentation

SQUID sensor principles, sensor tuning, quality control, phantom checks, empty room recording, helium management and cryogenic safety, magnetically shielded room operations

30%

Performing the Study

ACMEGS guidelines, troubleshooting, artifact identification, data acquisition, evoked field studies (AEF, SEF, VEF, LEF, MEF), epilepsy and tumor localization

20%

Post-Study Procedures

MEG data processing, MRI coregistration, montage design, filters, spike averaging, documentation, HIPAA, data management

10%

Pre-Study Preparation

Patient instructions, relevant history, neuroanatomy, infection prevention, electrode application, fiducial digitization, implanted device screening

How to Pass the CMEG Exam

What You Need to Know

Passing score: Criterion-referenced (board-determined minimum competency)
Exam length: Multiple-choice (count not publicly disclosed) questions
Time limit: 4 hours
Exam fee: $400

Keys to Passing

Complete 500+ practice questions
Score 80%+ consistently before scheduling
Focus on highest-weighted sections
Use our AI tutor for tough concepts

CMEG Study Tips from Top Performers

1Instrumentation is 40% of the exam — thoroughly understand SQUID sensor principles, the Josephson junction, flux-locked loops, and how superconductivity enables magnetic field detection

2Know helium management procedures: filling schedules, helium recycler operation, cryogenic safety protocols, and what happens if helium levels drop below critical thresholds

3Master the five evoked field types (AEF, SEF, VEF, LEF, MEF) — know the stimulus parameters, expected dipole locations, and clinical applications for each

4Understand MRI coregistration: fiducial placement (nasion, preauricular points), head digitization, coordinate transformation, and accuracy verification

5Study epilepsy MEG protocols: spike identification, averaging techniques, equivalent current dipole fitting, and how MEG complements EEG for surgical planning

Frequently Asked Questions

What is the CMEG exam?

The CMEG (Certified Magnetoencephalography Technologist) is an ABRET credential for neurodiagnostic technologists who specialize in magnetoencephalography. MEG uses SQUID sensors to detect magnetic fields from brain activity for epilepsy surgery planning and functional mapping.

How much does the CMEG exam cost?

The CMEG exam fee is $400 (per the current ABRET fee schedule). This was reduced from $700 in prior years. No refunds, extensions, or fee transfers are permitted.

What are the prerequisites for the CMEG exam?

Candidates must hold a current R.EEG.T. or R.EP.T. credential, have 6+ months supervised MEG experience, document 25 evoked and 50 spontaneous cases across 3+ modalities, complete ASET's 12-module MEG course, and hold current CPR/BLS.

What topics are most important for the CMEG exam?

MEG Instrumentation is the largest domain at 40% — master SQUID sensor principles, helium management, quality control procedures, and MSR operations. Performing the Study (30%) covers evoked field protocols and artifact management.

How long is the CMEG certification valid?

The CMEG credential is valid for 5 years. Recertification requires 15 hours of documented continuing education in MEG-related activities.

How is the CMEG exam administered?

The CMEG final exam is a proctored computer-based exam. Unlike other ABRET exams, it is proctored at a university or college testing center rather than through Prometric. Contact ABRET at info@abret.org for current scheduling details.