ways of studying brain

• fmri


  functional magnetic resonance imaging, detects changes in blood oxygenation and flow due to increased neural activity

  when more active consumes more oxygen so more blood flow to meet increased demand (haemodynamic response)

  creste 3D images called activation maps showing which parts involved in mental processes, important in understanding localisation
• eval of fmri


  strength - no radiation, risk free non invasive and straightforward if done correctly, high spatial resolution so shows clear picture of localisation safely

  limitation - expensive, poor temporal resolution as 5s time lag between neural activity and image, can’t truky represent moment to moment brain activity
• eeg


  electroencephalogram measures electrical activity by electrodes fixed to skull cap on ppt scalp

  scan recording represents brainwave patterns generated from activity of thousands of neurons, providing overall account of activity

  often used as diagnostic tool as arrhythmic patterns indicate abnormalities eg epilepsy and sleep disorders
• eeg evaluation 


  strength - useful in studying stages of sleep, diagnosis eg epilepsy characterised by random bursts, high temporal resolution as accurately detects brain activity at single millisecond RWA

  limitation - generalised nature of info received, that of many thousand neurons. EEG not useful for pinpointing exact source of activity, can’t distinguish between activity originating in different but adjacent locations
• post-mortems 


  technique involving analysis of person brain following death

  individuals whose brains subject to exam usually with rare disorder or unusual cognitive deficits

  areas of damage examined as measure of establishing likely cause of that disorder

  involve comparison to neurotypical brain to see extent of differences
• post mortem eval


  strength - vital in providing function for early understanding key processes in brain eg Broca used PM, HM showed damage associated with memory deficits, pioneered and useful in understanding decades before neuroimaging

  limitation - causation, damage may eg due to other trauma eg decay, ethical issues of informed consent before death and if capacity to consent eg HM, challenges usefulness in psych research
• erp 


  event related potential, EEG data in raw form is crude and generalised measure of activity, but contains all neural responses associated with specific events. erp is a way of isolating these using statistical averaging technique to filter all extraneous brain activity in EEG

  remaining is ERP which is types of brainwaves triggered by events
• ERP evaluation


  strength - brings specificity to measurement of neural processes more than EEG, devised form of EEG so high temporal resolution

  limitation - lack of standardisation in ERP methodology, between diff researchers diff statistical averaging technique used so hard to confirm findings