ways of studying the brain

• techniques for investigating the brain are often used for medical purposes in the diagnosis of illness. The purpose of scanning in psychological research is to investigate localisation to determine which parts of the brain do what
• fMRIs detects changes in both blood oxygenation and flow that occur due to neural activity in specific brain area. When an area is more active it consumes more oxygen and blood flow is directed to the active area. fMRI produces a 3D image showing which parts of the brain are active and therefore must be involved in particular mental processes
• ERPs are what is left when all extraneous brain activity from an EEG recording is filtered out. This is done using a statistical technique, leaving only those responses that relate to the presentation of a specific stimulus. Research has revealed many different forms of ERP and how these are linked to cognitive processes
• post-mortem examinations is a technique involving the analysis of a person's brain following their death. Areas of the brain are examined to establish the likely cause of a deficit or disorder that the person experienced in life. This may also involve comparison with a neurotypical brain in order to assess the extent of the difference
• One strength of fMRI is that it is risk free and high spatial resolution. Unlike other scanning techniques like PET, fMRI doesn't rely on the use of radiation and is safe. It also produces images with high spatial resolution, showing detail by the milimetre. This means fMRI can safely provide a clear picture of how brain activity is localised
• One limitation of fMRI is that it is expensive and has poor temporal resolution. fMRI is expensive compared to other techniques. It has poor temporal resolution because of 5-second lag between initial neural activity and image. This means fMRI may not truly represent moment to moment brain injury
• One strength of EEG is that it has practical uses and high temporal resolution. EEG has contributed to our understanding of the stages of sleep. It has high temporal resolution as it shows brain activity in one millisecond. This shows the real world usefulness of the technique
• One limitation of EEG is that information is generalised and source not pinpointed. The EEG produces a generalised signal from thousands of neurone. It is difficult to know the exact source of neural activity. Therefore EEG can't distinguish the activity of different adjacent neurones
• One strength of ERP is that is specific and has good temporal resolution. Measures of neural processes more scientific with ERPs than EEGs. ERPs have excellent temporal resolution which means that ERPs are frequently used in cognitive research
• One limitation of ERPs is the lack of standardisation and background nose. Lack of standardisation makes it difficult to confirm findings in studies involving ERPs. Background noise and extraneous material must be completely eliminated. These issues are a problem because they may not always be easy to achieve
• One strength of post-mortem is that there is medical research and it is in localisation. Broca and Wernike both relied on post mortem studies. Used to link HM's memory deficits to damage in the brain. This means they continue to provide useful information
• One limitation of post mortem is knowing causation and ethics. Observed damage in the brain may not be linked to the deficits under review. Post mortem studies raise ethical issues of consent after death like HM. This challenges their usefulness in psychological research