scanning techniques to identify brain functioning

Question 1

what are CT scans

Answer 1

Large doughnut-shaped scanner rotates around the person to take lots of X-rays of the brain.
Images are taken from different angles and are combined to build up a detailed picture.

Question 2

what are the strenght of ct scans

Answer 2

Useful for revealing abnormal structures like tumours.
Quality of the images provided is higher than traditional X-rays.

Question 3

what are the weaknesses of ct scans

Answer 3

equires more radiation than X-rays.
Only produces still images.

Question 4

what are PET scan

Answer 4

Patient is injected with a radioactive substance like glucose.
Brain activity shown on a computer screen.

Question 5

what are the strengths of PET scan

Answer 5

Shows brain in action.
Shows localisation of function when person asked to perform a specific task.

Question 6

what are the weaknesses of PET scan

Answer 6

Expensive.
Images difficult to interpret.
Ethical issues due to the injection of radioactive substance.

Question 7

what are fMRI scan

Answer 7

Measure changes in blood oxygen levels in the brain.
Brain activity displayed as 3D images produced on a computer screen.

Question 8

what are the strengths of fMRI scan

Answer 8

Shows brain in action.
Clear images.
No radiation.

Question 9

what are theweaknesses of fMRI scan

Answer 9

Expensive.
Person must stay very still.
Time lag between activity and image appearing.