ways of studying the brain

• what is a post mortum exam?

  • brain examined after death which shows stuctural abnormalities
  • case of HM - leisions and hippocampus
• what is a strength of post mortum examinations?

  can clearly see structural differences and damage
• what are the weaknesses of post mortum examinations?

  • unique cases
  • only shows structural damage
  • low sample size
  • death causes trauma
• what is an fMRi?

  • magnetic field and radio waves used to measure blood flow
  • measure changes in blood flow as specific tasks are performed - see what area is involved
• what are the strengths of fMRI scans?

  • safe, painless, non-invasive - can get more people
  • shows tumours and damage
• what are the disadvantages of fMRI scans?

  • very expensive
  • cannot be used with metallic devices i.e. pacemakers
• what is an EEG?

  • electrodes on scalp to detect neural activity
  • used to look at stages of sleep, sleep disorders and epilepsy
• what are the strengths of EEGs?

  • cheap
  • can see when a person is thinking
  • safe, painless and non-invasive
• what are the weaknesses of EEGs?

  • poor spatial resolution
  • restricted to neo-cortex -> cannot safely use for deeper in the brain
• what is an ERP?

  • electrodes placed on scalp measures neural activity WHEN presented with a stimuli / task
• what are the strengths of ERPs?

  • cheap so more research
  • ppts can be given different stimuli to see how processing works and in which area of the brain is activated
• what is the weakness of ERPs?

  • a number of trials are needed to obtain meaningful data