Ways of studying the brain

• What are the four ways of studying the brain?

  • fMRI
  • EEG
  • ERP
  • Post mortem examinations
• What does fMRI do?

  • Detects changes in blood flow to show active areas (where more oxygen is consumed)
  • Produces 3D image
• What do EEG do?

  • Measures electrical activity in the brain using a skull cap with electrodes
  • The scan represents brainwave patterns
  • An electrical signal is detected when multiple neurons fire at the same time to the same area
• What does and ERP do?

  • Uses averaging techniques to filter out the extra activity
  • Just focuses on the response to the specific stimulus from the EEG scanning
• What is a post mortem exam?

  • Dissects and analyses the brain after death
  • Checks for damage to establish likely cause of a deficit or disorder
• Strengths of fMRI:

  +High spatial resolution

  +Non invasive

  +Risk free
• Limitations of fMRI:

  -Poor temporal resolution

  -Expensive

  -Have to remain completely still

  -Delays in oxygen rates which the fMRI picks up
• Strengths of EEG:

  +Non invasive

  +Good temporal validity

  +Can be used while moving around

  +Real world applications e.g. sleep stages or diagnosing epilepsy
• Limitation of EEG:

  -Lacks spatial resolution
• Strengths of ERP:

  +Non invasive

  +Able to pinpoint response to specific event
• Limitations of ERP:

  -Difficult to average out the irrelevant activity

  -Different researchers use different averaging techniques
• Strengths of post mortem examinations:

  +Allow to see brain structures much more clearly

  +Provided foundation for studying the brain
• Limitation of post mortem examinations:

  -Brain damage is rarely confined to one area so hard to pinpoint the connection between damage and symptoms