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This comprehensive document contains 250 multiple-choice questions and detailed
rationales covering the EEG Board Exam (ABRET Registration Examination for
Electroencephalographic Technologists) content. Questions span all major domains
including instrumentation and electronics (amplifiers, filters, sampling rates,
impedance, common mode rejection), electrode placement (10-20 system,
landmarks, measurements), normal EEG patterns (posterior dominant rhythm,
alpha, beta, theta, delta, sleep spindles, vertex waves), benign variants (Mu rhythm,
lambda waves, BETS, breach rhythm), abnormal patterns (spikes, sharp waves,
PLEDs, BIPLEDs, triphasic waves, hypsarrhythmia, burst suppression), activation
procedures (hyperventilation, photic stimulation, sleep), artifacts (physiological
and environmental), pediatric EEG, digital EEG principles (sampling rate, aliasing,
Nyquist theorem), and clinical correlations (seizure types, encephalopathies,
prognosis). Each question provides four answer choices with the correct answer
identified and a comprehensive rationale explaining the underlying
neurophysiological principle, technical standard, or clinical application. This
resource thoroughly prepares candidates for the ABRET EEG Board Exam.
1. The basic unit for measuring current flow is:
A) Coulomb
B) Volt
C) Ampere
D) Ohm
Correct Answer: C
Rationale: The ampere is the base SI unit for electric current, measuring the rate
of flow of electric charge. The volt measures electrical potential, the ohm measures
resistance, and the coulomb measures electrical charge .
2. The basic unit of resistance is:
A) Coulomb
B) Volt
C) Ampere
, D) Ohm
Correct Answer: D
Rationale: The ohm is the SI derived unit of electrical resistance, quantifying
how much a material opposes the flow of electric current .
3. Which of the following is NOT a valid expression of Ohm's Law?
A) R = EI (or R = VI)
B) E = IR (or V = IR)
C) I = E/R (or I = V/R)
D) R = E/I (or R = V/I)
Correct Answer: A
Rationale: Ohm's Law states that voltage (E or V) equals current (I) times
resistance (R). The correct expressions are V = IR, I = V/R, and R = V/I. The
formula R = VI is incorrect .
4. Which of the following is NOT a unit for measuring alternating frequencies?
A) Cycles per second
B) Volts
C) Hertz
D) Kilocycles
Correct Answer: B
Rationale: Frequency, which measures how often a wave repeats per second, is
expressed in Hertz (Hz), cycles per second, or kilocycles. Volts are the unit for
measuring electrical potential, not frequency .
5. What is the time constant defined as?
A) The time required for the deflection to fall to 47% of the peak deflection
B) The time required for the deflection to fall to 57% of the peak deflection
C) The time required for the deflection to fall to 77% of the peak deflection
D) The time required for the deflection to fall to 37% of the peak deflection
Correct Answer: D
Rationale: The time constant is a measure of how quickly a system responds to a
change. In the context of EEG instrumentation, it is defined as the time required
for the deflection to fall to 37% of its peak deflection .
6. A high frequency setting of 35Hz would attenuate 50Hz muscle activity by
approximately what percentage:
A) 10%
B) 20%
C) 40%
, D) 60%
Correct Answer: C
Rationale: A high-frequency filter (HFF) attenuates frequencies above its cutoff.
Muscle activity at 50Hz would be significantly reduced. The correct percentage of
attenuation is approximately 40% .
7. An EEG record has 3/sec spike & wave discharges. Both the spike and the slow
wave have voltages of 100uV. If this discharge is recorded with a LFF of 5Hz and
a sensitivity of 10uV/mm, what would be the deflection of the spike and the wave?
A) spike 10mm & wave 6mm
B) spike 6mm & wave 10mm
C) spike 10mm & wave 10mm
D) spike 6mm & wave 6mm
Correct Answer: A
Rationale: The 5Hz low-frequency filter (LFF) will attenuate the slower 3Hz
wave but not the faster spike component. The spike would produce a deflection of
10mm (100uV / 10uV/mm), while the wave would be attenuated to 6mm .
8. During the recording of cerebral activity, the calibration input voltage is
changed from 50uV to 100uV. What will be the result?
A) No effect on the activity being recorded
B) A two-fold increase in amplitude
C) A one-half reduction of amplitude
D) Clipping of the waveform
Correct Answer: A
Rationale: The calibration signal is used to verify the instrument's sensitivity and
does not affect the patient's own EEG activity being recorded .
9. A spike is printed out on paper and measures 16mm peak to peak. The
sensitivity of the instrument is 7uV/mm and a calibration signal of 50uV causes a
deflection of 7.1mm. What is the voltage of the spike?
A) 1.2uV
B) 112uV
C) 12uV
D) 24uV
Correct Answer: B
Rationale: First, confirm the sensitivity: 50uV / 7.1mm = 7.04uV/mm
(approximately 7uV/mm). Then, multiply the spike's deflection by the sensitivity:
16mm * 7uV/mm = 112uV .
, 10. What input voltage is necessary to give a calibration deflection between 5 and
10mm if the sensitivity is 30uV/mm?
A) 10uV
B) 50uV
C) 100uV
D) 200uV
Correct Answer: D
Rationale: To achieve a deflection of 5-10mm at a sensitivity of 30uV/mm, you
need an input voltage of 150-300uV. The 200uV option falls within this acceptable
range .
11. According to ACNS Guidelines, the minimum sampling rate for EEG data
should be at least how many times the highest frequency filter setting?
A) 2
B) 2.5
C) 3
D) 4
Correct Answer: C
Rationale: ACNS guidelines recommend a minimum sampling rate of three
times the highest frequency filter setting to accurately reproduce the waveform and
avoid aliasing .
12. According to ACNS Guidelines for Recording Clinical EEG on Digital Media,
what is the minimum requirement for accurately displaying EEG on the monitor
screen?
A) Maximum of 1,000 data points/second
B) Minimum of 100 data points/second
C) Maximum of 100 data points/second
D) Minimum of 1,000 data points/second
Correct Answer: B
Rationale: The ACNS guidelines state that a minimum of 100 data points per
second is required to accurately display EEG on a monitor screen .
13. The filters creating a very narrow band pass that should RARELY be used
clinically are:
A) LFF 5.0Hz & HFF 70Hz
B) LFF 5.0Hz & HFF 15Hz
C) LFF 0.1Hz & HFF 70Hz
D) LFF 0.1Hz & HFF 15Hz
Correct Answer: B