STUDYING THE BRAIN

Question 1

fMRI AO1

Answer 1

→Uses magnetic field + radio signals to detect changes in blood oxygenation + flow that occurs as a result of brain activity in specific areas of the brain.
→When brain = more active it consumes more energy ∴ more blood directed to area to meet the incr demand (Haemodynamic response)
→produces 3D images

Question 2

fMRI AO3

Answer 2

Non invasive
High spatial resolution → detailed + clear image of how brain activity is localised
risk free → doesn’t rely on radiation

Can’t move
Poor temporal resolution →~ 5s lag between image on screen + initial neuron firing
Expensive compared to other techniques
Only measures blood flow to the brain → it cant one in on the activity of individual neurons ∴ cant exactly tell what kind of brain activity is being represented on the screen

Question 3

EEG (+ERP) AO1

Answer 3

→Uses electrodes to measure electrical activity
→ERP is same as EEG but stimulus presented to pts + look for activity related to the stimulus. Using statistical averaging technique, all brain activity from EEG can be filtered out + so only leaves response related to the task

Question 4

EEG (+ERP) AO3

Answer 4

Good temporal resolution (ERP + EEG)
Diagnostic tool → e.g, epilepsy characterised by random bursts of brain activity that can be detected on the screen
Contributed to our understanding of stages of sleep

Poor spatial resolution → is the generalised nature of info received. The electrodes are not sensitive enough + it lacks precision in measuring individual action potentials of neurons ∴ does not allow researcher to distinguish between activities originating in different but adjacent locations BUT ERP addresses these issues BUT to get pure data background info must be completely eliminated + this is hard to achieve

Question 5

POST-MORTEM EXAM AO1

Answer 5

→brain analysed after death to determine if certain behaviours of the pts can be linked to abnormalities in the brain

Question 6

POST-MORTEM EXAM AO3

Answer 6

Improve medical knowledge + help generate hypothesis for further studies
detailed examination of the anatomical structure and neurochemical aspects of the brain not possible w/ scanning techniques

Invasive but dead
ethical issues → informed consent: carried out on pts w/ severe psychological deficits ∴ unable to provide fully informed consent
Causation is an issue as observed damage to the brain may not be linked to the deficits under review, could be an unrelated trauma / decay