ways of studying the brain

AO1

  • fMRIs - work on the basis that areas of the brain which are being used need more blood flow to provide O2 for respiration (haemodynamic response)

  • they detect radio waves from changing magnetic fields and produce 3D images showing which parts of the brain are activated

  • this can be used to understand localisation of function

  • EEG - measures electrical activity of the brain via electrodes attached to a skull cap

  • electrical impulses are released when neurons fire and an EEG picks up on these

  • they produce wave patterns, suggesting the state of the brain

  • an arrhythmic pattern may suggest the presence of anbormalities

  • can be used as a diagnostic tool

  • event related potentials (ERPs) - similar to EEGs

  • for one specific neural response to stimuli - showing ppt stimuli and repeatedly recording brain activity

    • produces raw EEG which is processed to remove non brain related electrical noise and is further statistically analysed to produce an ERP wave associated with the specific cognitive processes

  • therefore, ERPs are useful tools to understand specific cognitive processes

AO3

  • one strength of using fMRIs is that it is a very safe method of studying the brain

  • this is beneficial because it is a more ethical way of studying living individuals, in comparison to radiation or invasive method

  • this means that people may feel more compelled to take part in research, resulting in larger, more representative samples and reliable data

  • it also allows for faster and more widespread treatment because it is suitable to used in the healthcare setting

  • therefore, fMRIs have strong real world applicability and importance

  • a weakness of fMRIs is that is has a very poor temporal resolution

  • unlike other techniques, there is a noticeable lag between when neurons are fired and when brain activity is recorded (5sec)

  • this means that fMRIs are not entirely reliable to use to understand immediate brain activity, limiting its usage in research

  • therefore, fMRIs are not accurate in showing what is occurring in the brain at a specific time frame, such as immediately after a stimuli is shown

  • a strength of ERPs are that they are an improvement on raw EEG data, due to their specificity

  • this allows for better understanding of direct responses to stimuli as they have excellent temporal resolution, allowing researchers to see the almost exact moment the brain and certain regions of it respond to stimuli

  • this allows for the creation of many cognitive models, such as the WMM

  • therefore, ERPs have strong RWA

  • a strength of EEGs is that they are often used to understand sleep in humans but the caps used can sometimes be uncomfortable

  • this could means that the ppt struggles to sleep, limiting data researchers can achieve

  • furthermore, ppts may scratch, move or pull at the cap, which could reduce the validity of findings. noticing the cap could also skew the findings

  • therefore, while EEGs provide better temporal resolutions it may be limited in understanding certain processes due to its methodology not being ideal for ppt.