WAYS OF STUDYING THE BRAIN

• ERP (event related potential)


  Measures the changes in voltages produced by brain signals in response to stimuli. It is non-invasive but is only superficial and the voltages are hard to differentiate between.
• fMRI (functional magnetic resonance imaging)


  Uses a big magnet to track blood flow in the brain. The principle is that blood will go to the brain area that's being used in response to stimuli. It is non-invasive, objective and reliable however the fact it only measures blood flow is limiting because we cannot be certain this means that that is the brain part being used. It also overlooks holism and may be too reductionist.
• EEG (electroencephalogram)


  Uses electrodes attached to the scalp to measure electrical brain activity. A graph is produced as a result of this by a machine. Again, this is limited by the fact that it only picks up on superficial electrical signals and the signals are hard to differentiate between but it is useful for diagnostics.
• Post-mortem


  Cutting up a dead person. This is an invasive procedure however this is not an ethical concern because the patient is dead and unable to be bothered by it. However, cadavers are hard to come by as it is of utmost importance to receive prior consent from the patient and cadavers must also be stored properly and worked with quickly or else they will rot. It is used to establish neurobiology and is objective. It is detailed and different brain structures are physically observable. This method was used by both Broca and Wernicke (patients with same symptoms all had lesions on same brain areas). Another limitation of it is that the tissue is obviously dead and therefore unresponsive so we cannot measure responses to stimuli.
• fMRI and ECG


  • Produce physically observable results
  • Objective and scientific
  • Non-invasive
  • Conducted on live patients who can offer introspection and respond to stimuli
• fMRI


  Is the best method
• Blood flow=brain in use

  Highly likely
• Stroke patients


  • Blood clot in the brain means certain brain areas stop receiving adequate oxygen and thus function of those areas is lost or reduced
• ECG


  • Can only measure superficial impulses which leads to deeper brain impulses and functions being overlooked
• fMRI


  • Produces clear images as opposed to graphs that require interpretation
• fMRIs can be distressing especially for children and people with reduced intellect who cannot process and understand what is happening
• Those with claustrophobia or autistic spectrum conditions may also be distressed by the small, loud machine that you must lie in
• mri=low temporal resolutiom
• eeg= very high temporal res
• erp= very high temporal res
• erp-Poor methodology - lack of standardisation, resulting in difficulty confirming credibility of findings. Also, for pure data needs to be no background noise and extraneous material; which is hard to achieve, as they involve having activity to observe.