Brain Scans

Question 1

What does a CAT scan use to get information

Answer 1

Uses x-ray plus computer to create detailed structure of brain

Question 2

If someone is getting a CAT scan, what do they do?

Answer 2

They lie down inside scanner and rotates around them

Question 3

What does a CAT scan image show?

Answer 3

Cross-section of brain/body

Question 4

Advantages of CAT scan

Answer 4

Reveal abnormal structures in the brain
Quality of images are a lot higher than x-rays

Question 5

Disadvantages of CAT scan

Answer 5

Require more radiation than x-rays because they are more detailed and complex
Only provide structural information, not activity

Question 6

What does a PET scan measure?

Answer 6

Metabolic activity in brain in most active areas

Question 7

How can you see the active areas of the brain with a PET scan?

Answer 7

Injection with radiotracer and the most active areas will use more of it

Question 8

What do the different colours of a PET scan show

Answer 8

Red/yellow = most active
Green/blue = least active

Question 9

Advantages of PET scan

Answer 9

Brain in action
Indicate specific areas of the brain that are involved
Valid – scan measures what it claims to measure
Reliable – repeated and same results found

Question 10

Disadvantages of PET scan

Answer 10

Results are not easy to interpret
Injection is invasive so there are ethical problems
Expensive
Precise location of active areas in relation to brain structure is difficult to pinpoint

Question 11

Type of waves does a fMRI can use

Answer 11

Radio waves

Question 12

What do the radio waves in an fMRI scan measure?

Answer 12

Oxygen levels in the brain

Question 13

Describe the relationship between active areas of the brain and oxygen in an fMRI scan

Answer 13

The most active areas of the brain use the most oxygen so blood is directed there

Question 14

How is the brain activity picked up in an fMRI scan?

Answer 14

Activity is picked up by radio signals and 3-D image on computer

Question 15

Advantages of fMRI scan

Answer 15

Important information about used areas
No radiation used and non-invasive
Images of clear and shown to the millimetre
Record signal from all regions of the brain

Question 16

Disadvantages of fMRI scan

Answer 16

Expensive
Only effective if they stay perfectly still
Five second time lag between brain activity and image on screen
Very noisy
Must be interpreted carefully