Discuss scanning techniques as a way of investigating the brain. [16 marks]

AO1

• fMRI (functional magnetic resonance imaging)

  • use of magnets and radiowaves to detect oxygen concentration, so measure blood flow to active brain areas, active areas demand higher oxygen supply due to aerobic respiration

• EEG (electroencephalogram)

  • detects electrical activity (brainwaves) through electrodes attached to the scalp

• ERP (event-related potential)

  • isolates EEG data to extrapolate the specific effect of a stimulus on brain activity

• Post-mortem

  • dissection of a brain after death, commonly performed on people who had mental abnormalities when alive, identification of damaged areas allows psychologists to correlate structure with function

AO3

• ERPs have no standardised method of working on data

• It is very tricky to remove all background ‘noise’ for an ERP

• EEGs have better temporal resolution than fMRIs

• EEGs are key in the diagnosis of epilepsy, real-world value

• fMRIs have better spatial resolution, allows localisation of function to be established

• fMRIs are expensive :(

• Post-mortems produce correlational findings, damage may have been incurred after death

• Post-mortems allow physically deeper analysis of the brain

• Post-mortems aren’t always performed with consent e.g. HM