Ways of investigating brain

• fMRI is a non-invasive test that uses a strong magnetic field and radio waves to create detailed images of body. fMRI looks at blood flow in the brain to detect areas of activity. Change in blood flow/changes in O2 captured on a computer, and help us understand more about how the brain works.
• S of fMRI - unlike other scanning techniques such as PET, it does not rely on the use of radiation. If administered correctly it's virtually risk-free, non-invasive and straightforward to use. It also produces images that have very high spatial resolution, depicting detail by the mm, and providing a clear picture of how brain activity is localised. This means that fMRI can safely provide a clear picture of brain activity.
• W of fMRI - expensive compared to other neuroimaging techniques. Poor temporal resolution because there is around a 5-second time-lag behind the image on screen and the initial firing of neuronal activity. This means fMRI may not truly represent moment-to-moment brain activity.
• Electroencephalogram (EEG) - This is a recording of general brain activity. During test small sensors are attached to the scalp to pick up electrical signals produced when brain cells send msgs to each other. Characteristic wave patterns can help diagnose certain conditions of the brain I.e. Epilepsy and sleep disorders.
• S of EEG - useful in studying the stages of sleep and in the diagnosis of conditions such as epilepsy, a disorder characterised by random bursts of activity in the brain that can easily be detected on screen. Unlike fMRI, EEG technology has extremely high temporal resolution. Today's EEG technology can accurately detect brain activity at a resolution of a single millisecond (and even less in some cases). This shows the real-world usefulness of the technique.
• W of EEG - drawback is the generalised nature of the information received. The EEG signal is also not useful for pinpointing the exact source of neural activity. Therefore it does not allow researchers to distinguish between activities originating in different but adjacent locations.
• event related potential (ERP)- the measured brain response that is the direct result of a specific sensory, cognitive, or motor event which can be statistically analysed through EEG data. Stimulus is presented many times and average response is grafted over time (averaging)  
• S of ERP - bring much more specificity to the measurement of neural processes than could ever be achieved using raw EEG data. As ERPs are derived from EEG measurements, they have excellent temporal resolution, especially when compared to neuroimaging techniques such as fMRI. This means that ERPs are frequently used to measure cognitive functions and deficits such as the allocation of attentional resources and the maintenance of working memory.
• W of ERP - Critics have pointed to a lack of standardisation in ERP methodology between different research studies which makes it difficult to confirm findings. A further issue is that, in order to establish pure data in ERP studies, background 'noise' and extraneous material must be completely eliminated. This is a problem because it may not always be easy to achieve.
• Post-mortem examinations - a technique involving the analysis of a person's brain following death. In psych research, individuals whose brains are subject to PME are likely to be those who have a rare disorder and have experienced unusual deficits in mental processes or behaviour during lifetime. Areas of damage within the brain are examined after death as a means of establishing likely cause of the affliction the person experienced. May also involve comparison with a neurotypical brain in order to ascertain the extent of the difference.
• S of PME - vital in providing a foundation for early understanding of key processes in the brain. Paul Broca and Karl Wernicke both relied on post-mortem studies in establishing links between lang, brain and behaviour decades before neuroimaging ever became a possibility. Post-mortem studies were also used to study HM's brain to identify the areas of damage, which could then be associated with his memory deficits. This means post-mortems continue to provide useful information.
• W of PME - Causation is an issue within these studies. Observed damage to the brain may not be linked to the deficits under review but to some other unrelated trauma or decay. A further problem is that post- mortem studies raise ethical issues of consent from the individual before death. P's may not be able to provide informed consent, e.g. the case of HM who lost his ability to form memories and was not able to provide such consent - nevertheless post-mortem research has been conducted on his brain. This challenges the usefulness of post-mortem.
• Spatial resolution - Level of accuracy in identifying exact location of brain structure/activity in space (where activity happened)
• Temporal resolution - Level of accuracy in identifying exact location of brain activity in time (when it happened)
• Name 4 ways of investigating the brain

  • EEG
  • fMRI
  • ERP
  • Post-mortem examination/dissection