ways of investigating the brain

Question 1

erp

Answer 1

brains response to specific events are isolated by doing a statistical analysis of EEG data , filtering out all but those that relate to showing of a specific stimulus.
diffrent types of erp have been linked to attention and perception

Question 2

strengths of erp

Answer 2

excellent temporal resolution
widely used in the measurement of cognitive defecits and functions

Question 3

weaknesses of erp

Answer 3

lack of standarisdation in erp methodology in different research studies
background noise and extraneous metrial can be an obstacle

Question 4

fmri scans

Answer 4

rely on haemodynamic repose
high level of activity = higher oxygenated blood , leading to higher rate of blood deoxygenation
deoxyhaemoglobin in blood in highly active areas absorbs signal produced by scan and appears bright coloured on scan

Question 5

fmri scans strength

Answer 5

high spatial resolution unto 4 images per second
can be used while a patient is carrying out a task , helping make inferences about brain function and localisation
does not use ionising radiation unlike PET scans so is safer

Question 6

fmri scans weakness

Answer 6

poor temporal resolution , approx 5 seconds difference between neuronal activity and produced image

Question 7

eeg scans

Answer 7

electrodes attached to scalp , measures electric activity across whole brain

Question 8

eeg scans strength

Answer 8

paritucarly useful in investigating the charasterics of the different stages of sleep demonstrated by dement and kleitman
much higher temporal resolution than fmri scans
useful in diagnosis of epilepsy , characterised by random, bursts of activity

Question 9

eeg scans weakness

Answer 9

lower spatial resolution compared to fmri scans

Question 10

post mortem examinations

Answer 10

comparison of patients brain with that of a neurotypical healthy brain
any differences are assumed to have caused the neurological problems in their life

Question 11

post mortem strengths

Answer 11

particularly useful for advancing medical knowledge and being the basis of further research into certain ares of the brain eg tan and brocas area

Question 12

post mortem weakness

Answer 12

incorrectly makes assumptions that differences found explain neurological or cognitive deficits , prolonged drug use , stress and genetic factors may be plausible explanations
ethical issues arise because informed consent cannot always be obtained before the patient dies ie HM suffered from defects in STM so would not remember signing