Ways of Studying the Brain

Created by

Lauren

Cards (9)

Ways of Studying the Brain: Scanning Techniques:
> functional magnetic resonance imaging (fMRI)
> electroencephalograph (EEG)
> event-related potentials (ERPs)
> post-mortems
fMRI:
> identifies changes in levels of oxygen in blood that occurs due to brain activity in specific areas
> brain area is more active = more oxygen used = increase of blood flow to the area
> produces a 3D image showing active brain area - activation map
> used to identify active brain areas in particular mental processes (localisation)
fMRI AO3:
:) Safer - non-invasive and doesn't use radiation, unlike PET scans
:)/:( High spatial resolution, but poor temporal resolution - 5 second time lag
EEG:
> electrodes placed on scalp using a skull cap - they detect small electrical changes from the activity of brain cells
> the electrical changes are graphed over a period of time to see general brain activity
> used to detect sleep patterns and states, such as sleep or arousal
> used as a diagnostic tool for conditions such as brain tumours and epilepsy
EEG AO3:
:) High temporal resolution
:( Low spatial resolution
ERPs:
> electrodes placed on scalp - unlike an EEG, an ERP shows specific brain activity
> stimulus is presented to an individual many times and brain activity is measured in same way as an EEG - all extraneous activity is then filtered out, leaving only the responses that link to the presentation of the stimulus
> ERPs remain - types of brainwaves triggered by particular events
ERPs AO3:
:) High temporal resolution
:( Affected by external factors
Post-mortems:
> brain of a dead patient is examined and dissected to see if there are any physical abnormalities
> the brain is compared with a brain that does not show this behaviour or mental process
> mainly used on people with rare disorders or defects
> example: Broca's area discovered through post-mortem
Post-mortem AO3:
:) Invasive = more detailed
:( Hard to establish cause and effect due to confounding variables