Ways of studying the brain

• Functional magnetic resonance imaging (fMRI): A method used to measure brain activity while a person is performing a task. fMRI detects radio waves from changing magnetic fields. This enables researchers to detect which regions of the brain are rich in oxygen and thus active.
• Electroencephalogram (EEG): A record of the tiny electrical impulses produced by the brain's activity. By measuring characteristic wave patterns, the EEG can help diagnose certain conditions of the brain.
• Event-related potentials (ERPs): The electrophysiological response of the brain to a specific sensory, cognitive or motor event can be isolated through statistical analysis of EEG data.
• Post-mortem examinations: The brain is analyzed after death to determine whether certain observed behaviours during the persons lifetime can be linked to structural abnormalities in the brain.
• fMRI Further explanations:

  • Detects change in blood oxygenation and flow that occur as a result of brain activity.
  • When the brain area is more active it consumes more oxygen, this means there is more blood flow to those parts of the brain.
  • Produces three-dimensional images showing which parts of the brain are most active.
• EEG Further explanations:

  • Measures electrical activity in the brain via electrodes that are fixed to an individuals scalp using a skull cap.
  • The scan recording represents brainwave patterns, generated from the actions of neurons.
  • Often used as a diagnostic tool.
• ERP's Further explanations:

  • All extraneous brain activity from the original EEG recording is filtered out leaving only responses to the presentation of a specific stimuli.
  • Isolates the specific response to an activity.
• Post-Morten examinations further explanations:

  • The analysis of the brain after a persons death, normally those who has a rare disorder.
  • May compare the persons brain to a healthy brain.
• fMRI Evaluation (strength):

  • Doesn't rely on the use of radiation.
  • Produces clear images of the brain.
• fMRI Evaluation (limitation):

  • Very expensive compared to other techniques.
  • Poor temporal resolution causing a lag, this means that it may not truly represent moment to moment brain activity.
• EEG Evaluation (Strength):

  • Useful in studying the stages of sleep and in diagnosing certain conditions.
  • Has a high temporal resolution meaning there is no lag.
• EEG Evaluation (limitation):

  • The signal is not good at pinpointing the exact source of activity.
• ERP Evaluation (strength):

  • Bring more specificity to the measurement of neural processes.
  • Good temporal resolution.
• ERP Evaluation (limitation):

  • Lack of standardisation in methodology.
  • To get pure data background noise must not be there making it difficult to gain real data.
• Post-Mortem Evaluation (Strength):

  • Vital for providing a solid foundation for early understanding of key processes.
  • Used by Wernicke and Broca
• Post-Mortem Evaluation (limitation):

  • Raise ethical issues, did they get consent to study the persons brain before they died.
  • Observed damage to the brain may not be the cause of the disease they are looking for.