ways of studying the brain

• Spatial resolution is the extent to which the scanner provides a detailed image of the brain
• Temporal resolution refers to the accuracy of the scanner in terms of how long it takes between the brain activity and the measurement being taken
• Invasiveness refers to the use of radiation or inserting instruments directly into the brain
• Causality refers to creating a cause and effect relationship between the activity and the stimulus
• FMRI is a non-invasive way of studying the brain that works by detecting the changes in blood flow.
• FMRI steps:

  1. participant lies in the scanner, ensuring they have no metal on them
  2. when haemoglobin in the blood has oxygen, it reacts differently to magnetic stimulation
  3. scanners use a magnet to measure amount of haemoglobin
  4. FMRI can detect when the brain is active and uses more oxygen and glucose
  5. FMRI produces a 3D image (activation map)
  6. It does this within 1-4 seconds
  7. It detects activity with a precision of 1-2mm
• Evaluation of FMRI

  🙂 high spatial resolution

  ☹️ low temporal resolution
• EEGs are a non-invasive way of measuring electrical activity. They are used to record general brain activity like sleep.
• Evaluation of EEGs

  🙂 High temporal resolution (milliseconds)

  ☹️ Low spatial resolution
• ERPs use the same equipment as EEGs and also measure electrical activity of the brain. The difference is that they record activity in response to a specific stimulus that is presented to the participant.
• Evaluation of ERPs

  🙂 High temporal resolution

  ☹️ Low spatial resolution
• Post-mortems is when a persons brain is analysed after death. They are usually done in people who have had a psychological/ developmental disorder. They establish the cause of any problems that they had when they were alive.
• Post-mortems physical examinations look for

  • Anatomical structure
  • Neurochemistry
• Evaluation of post-mortems

  🙂 high level of detail

  ☹️ post-mortems don’t show brain activity