PET scan

• What type of scan is a PET scan?

  Functional
• What is the procedure of a PET scan?

  1. A radioactive glucose tracer is injected into the arm, tracer travels to the brain where it metabolises glucose
  2. If a region of the brain is more active, it will metabolise more glucose relative to other areas of the brain
  3. Tracer decays and emits positrons
  4. Positrons collide with electrons and forms gamma rays
  5. Gamma rays are detected by the scanner
  6. Scan shows areas which are most active (hotspots = red/orange)
  7. These are dislayed as images
• What is a PET scan?

  > Shows how well certain parts of the body are working rather than just an image

  > Show where cells are more active than normal
• How can a PET scan helpful psychology?

  Establish levels of activity in areas of the brain which link to aggression
• What are the strengths of PET scans?

  > Images can be checked by other researchers - reliable

  > Sensitive, detects neurotransmitters & receptors - links to behaviour
• What are the weaknesses of PET scans?

  > More invasive, requires an injection, damage cells - ethical

  > Locate generalised areas - harder to draw conclusions