ADVANCED EEG BOARD EXAM
(ABRET/REGT PREPARATION) EXAM
PREP QUESTIONS AND ANSWERS 100%
VERIFIED. JUST RELEASED
1. A differential amplifier has a Common Mode Rejection Ratio (CMRR) of 80 dB. What is the
ratio of the differential gain to the common-mode gain?
A. 100:1
B. 1,000:1
C. 100,000:1
D. 10,000:1
Answer: D
Conceptual Explanation: CMRR in dB is calculated as 20 * log10(Ratio). 80 dB
corresponds to a ratio of 10,000:1. This is a critical specification for EEG amplifiers to
minimize noise.
,2. When measuring the 10-20 system, what is the distance from the Nasion to Fpz if the total
distance from Nasion to Inion is 36 cm?
A. 1.8 cm
B. 3.6 cm
C. 7.2 cm
D. 10.0 cm
Answer: B
Conceptual Explanation: The distance from Nasion to Fpz is 10% of the total Nasion-to-
Inion distance. 10% of 36 cm is 3.6 cm.
3. Which of the following describes a phase reversal in a bipolar montage?
A. Two channels sharing a common electrode show deflections in opposite directions.
B. The activity is restricted to one electrode only.
C. The activity is seen in all channels with the same polarity.
D. A deflection that occurs only in the reference electrode.
Answer: A
Conceptual Explanation: A phase reversal occurs in a bipolar montage when two channels
share a common electrode and the input signal at that electrode causes the pens to move in
opposite directions, helping localize a focus.
, 4. If the sensitivity is 7 uV/mm and a wave measures 10 mm in height, what is the voltage of
the wave?
A. 0.7 uV
B. 1.4 uV
C. 70 uV
D. 700 uV
Answer: C
Conceptual Explanation: Voltage = Sensitivity x Amplitude. Therefore, 7 uV/mm * 10 mm
= 70 uV.
5. What is the effect of increasing the Low Frequency Filter (LFF) from 1 Hz to 5 Hz?
A. It will increase the amplitude of slow waves.
B. It will decrease the amplitude of slow waves.
C. It will decrease the amplitude of fast activity.
D. It will increase the amplitude of fast activity.
Answer: B
Conceptual Explanation: Increasing the LFF (or High Pass Filter) cuts more low-
frequency activity, thus decreasing the amplitude of slow waves.
(ABRET/REGT PREPARATION) EXAM
PREP QUESTIONS AND ANSWERS 100%
VERIFIED. JUST RELEASED
1. A differential amplifier has a Common Mode Rejection Ratio (CMRR) of 80 dB. What is the
ratio of the differential gain to the common-mode gain?
A. 100:1
B. 1,000:1
C. 100,000:1
D. 10,000:1
Answer: D
Conceptual Explanation: CMRR in dB is calculated as 20 * log10(Ratio). 80 dB
corresponds to a ratio of 10,000:1. This is a critical specification for EEG amplifiers to
minimize noise.
,2. When measuring the 10-20 system, what is the distance from the Nasion to Fpz if the total
distance from Nasion to Inion is 36 cm?
A. 1.8 cm
B. 3.6 cm
C. 7.2 cm
D. 10.0 cm
Answer: B
Conceptual Explanation: The distance from Nasion to Fpz is 10% of the total Nasion-to-
Inion distance. 10% of 36 cm is 3.6 cm.
3. Which of the following describes a phase reversal in a bipolar montage?
A. Two channels sharing a common electrode show deflections in opposite directions.
B. The activity is restricted to one electrode only.
C. The activity is seen in all channels with the same polarity.
D. A deflection that occurs only in the reference electrode.
Answer: A
Conceptual Explanation: A phase reversal occurs in a bipolar montage when two channels
share a common electrode and the input signal at that electrode causes the pens to move in
opposite directions, helping localize a focus.
, 4. If the sensitivity is 7 uV/mm and a wave measures 10 mm in height, what is the voltage of
the wave?
A. 0.7 uV
B. 1.4 uV
C. 70 uV
D. 700 uV
Answer: C
Conceptual Explanation: Voltage = Sensitivity x Amplitude. Therefore, 7 uV/mm * 10 mm
= 70 uV.
5. What is the effect of increasing the Low Frequency Filter (LFF) from 1 Hz to 5 Hz?
A. It will increase the amplitude of slow waves.
B. It will decrease the amplitude of slow waves.
C. It will decrease the amplitude of fast activity.
D. It will increase the amplitude of fast activity.
Answer: B
Conceptual Explanation: Increasing the LFF (or High Pass Filter) cuts more low-
frequency activity, thus decreasing the amplitude of slow waves.
