International 10-20 Quiz

1. What electrode site is half way between T3 and T4?

F4

Cz

Pz

C3

Cz, also known as the vertex or Cz electrode site, is located at the top of the head. It is considered the midpoint between T3 and T4, which are electrodes placed on the left and right temporal lobes, respectively. Therefore, Cz is the electrode site that is halfway between T3 and T4.

Explanation

Cz, also known as the vertex or Cz electrode site, is located at the top of the head. It is considered the midpoint between T3 and T4, which are electrodes placed on the left and right temporal lobes, respectively. Therefore, Cz is the electrode site that is halfway between T3 and T4.

2. What electrode site is between Pz and T6?

T4

P4

O2

T3

The electrode site between Pz and T6 is P4.

Explanation

The electrode site between Pz and T6 is P4.

3. What electrode site is between T3 and O1?

F7

P3

C3

T5

The electrode site between T3 and O1 is T5.

Explanation

The electrode site between T3 and O1 is T5.

4. If the measured circumference of a patient is 60cm what is the distance between Fpz and T4?

15cm

18cm

21cm

23cm

The distance between Fpz and T4 is 15cm.

Explanation

The distance between Fpz and T4 is 15cm.

5. If the measured distance between Fp1 and O1 is 32cm what is the distance from F3 to P3?

13cm

18cm

15cm

16cm

Based on the given information, the distance between Fp1 and O1 is 32cm. Since F3 and P3 are corresponding locations to Fp1 and O1 respectively, it can be assumed that the distance between F3 and P3 would also be 32cm. Therefore, the correct answer is 16cm, as it is the only option that matches the given distance.

Explanation

Based on the given information, the distance between Fp1 and O1 is 32cm. Since F3 and P3 are corresponding locations to Fp1 and O1 respectively, it can be assumed that the distance between F3 and P3 would also be 32cm. Therefore, the correct answer is 16cm, as it is the only option that matches the given distance.

6. What electrode site is between Fp2 and T4?

F4

F8

Fz

P4

F8 is the electrode site that is located between Fp2 and T4.

Explanation

F8 is the electrode site that is located between Fp2 and T4.

7. If the measured distance from Nasion to Inion is 36cm what is the distance between Fpz and Fz?

7.2cm

6.8cm

10.8cm

8cm

The distance between Fpz and Fz can be calculated by dividing the measured distance from Nasion to Inion by 5, as Fpz is one-fifth of the distance from Nasion to Inion. Therefore, if the distance from Nasion to Inion is 36cm, the distance between Fpz and Fz would be 7.2cm.

Explanation

The distance between Fpz and Fz can be calculated by dividing the measured distance from Nasion to Inion by 5, as Fpz is one-fifth of the distance from Nasion to Inion. Therefore, if the distance from Nasion to Inion is 36cm, the distance between Fpz and Fz would be 7.2cm.

8. If the measured circumference is 58cm what is the distance between Fpz and Oz?

29cm

27cm

18cm

35cm

Based on the given information, the measured circumference is 58cm. The distance between Fpz and Oz is not directly mentioned in the question, but it can be inferred that the distance is half of the measured circumference. Therefore, the distance between Fpz and Oz is 29cm.

Explanation

Based on the given information, the measured circumference is 58cm. The distance between Fpz and Oz is not directly mentioned in the question, but it can be inferred that the distance is half of the measured circumference. Therefore, the distance between Fpz and Oz is 29cm.

9. If the measured distance between the left and right pre-auricular curves are 41cm what is the distance between C3 and C4?

20.5cm

14cm

18.2cm

16.4cm

The distance between the left and right pre-auricular curves is given as 41cm. Since the pre-auricular curves are on either side of the head, the distance between them can be considered as the width of the head. The distance between C3 and C4 is likely to be half of the width of the head, which would be 20.5cm. However, the correct answer is given as 16.4cm. Without further information or context, it is unclear why this is the correct answer.

Explanation

The distance between the left and right pre-auricular curves is given as 41cm. Since the pre-auricular curves are on either side of the head, the distance between them can be considered as the width of the head. The distance between C3 and C4 is likely to be half of the width of the head, which would be 20.5cm. However, the correct answer is given as 16.4cm. Without further information or context, it is unclear why this is the correct answer.

10. If the measured distance from FPz to Fz is 22cm, what is the distance from Fz to F4?

11cm

6.5cm

5.5cm

4.4cm

In the 10-20 EEG system, electrode placement is based on proportional distances between landmarks on the skull. The distance between Fz (midline frontal) and F4 (right frontal) is half the distance between FPz (pre-frontal midline) and Fz. Therefore, if the distance from FPz to Fz is 22cm, the distance from Fz to F4 would be 11cm.

Explanation

In the 10-20 EEG system, electrode placement is based on proportional distances between landmarks on the skull. The distance between Fz (midline frontal) and F4 (right frontal) is half the distance between FPz (pre-frontal midline) and Fz. Therefore, if the distance from FPz to Fz is 22cm, the distance from Fz to F4 would be 11cm.