EEG Electrode Placement and Montages 5

Question 1

Which montage type is most useful for localizing the PHASE REVERSAL of an epileptiform discharge?

Accepted Answer

Bipolar montage

Answer

Bipolar montages are best for localizing epileptiform discharges because phase reversals occur at the electrode directly over the focus.

Question 2

In the revised IFCN electrode nomenclature, electrode T5 is now called:

Accepted Answer

P7

Answer

In the revised nomenclature, T5 was renamed P7 because it overlies the posterior temporal/parietal region, not the mid-temporal region.

Question 3

A technologist notices a phase reversal at F7 in a bipolar montage. What does this indicate?

Accepted Answer

Maximum electrical activity at F7

Answer

In a bipolar montage, phase reversal at a specific electrode indicates that the maximum (or focus of) electrical activity is located at that electrode.

Question 4

How many electrodes are used in the standard 10-20 system?

Accepted Answer

21

Answer

The standard 10-20 system uses 21 electrodes, including 19 scalp electrodes plus A1 and A2 ear reference electrodes.

Question 5

Which electrode site is used as the nasion landmark in the 10-20 measurement system?

Accepted Answer

The bridge of the nose between the eyes

Answer

The nasion is the depression at the bridge of the nose between the eyes and serves as the anterior skull landmark for 10-20 measurements.

EEG - Electroencephalography Practice Test

EEG - Electroencephalography Practice Test

EEG Electrode Placement and Montages 5