Ways of Studying Brain

Question 1

how do fMRIs study the brain

Answer 1

(Functional Magnetic Resonance Imaging)
- measure blood flow in brain in brain when person performs a task
- increased demand for oxygen = causes increased blood flow = more active brain region

Question 2

how do EEGs study the brain

Answer 2

(Electroencephalogram)
- measures electrical activity in the brain
- typical activity patterns include; alpha, beta, theta, delta waves
- signals = graphed and can be used to detect certain types of disorders (e.g. Alzheimer’s disease)

Question 3

how do ERPs study the brain

Answer 3

(Event-Related Potentials)
- technique can demonstrate how processing is affected by specific stimuli
- same as EEG but looks at activity stimuli-related
- waves occur after 100ms = cognitive
- waves occur within 100ms = sensory

Question 4

how can the brain be studied through post mortem examination

Answer 4

• enables researchers to perform more detailed examination of anatomical structure of brain
  e.g. Broca with Tan

Question 5

temporal resolution (how quickly changes detected) of EEGs, ERPs, and fMRIs

Answer 5

EEG/ERP = high (1-10ms)
fMRI = low (1-4s)

Question 6

spatial resolution (smallest feature detected) of EEGs, ERPs, and fMRIs

Answer 6

fMRI = high (1-2mm)
EEG/ERP = low (superficial, only general regions)

Question 7

invasiveness of ways of studying brain

Answer 7

fMRI/EEG/ERP = non-invasive = do not use radiation/insertion of instruments directly into brain (unlike PETs) = virtually risk-free

Question 8

level of causation established by ways of studying brain

Answer 8

fMRI/EEG/Post-mortem = do not display direct causation
- fMRI simply measure blood flow changes
- EEG tend to detect electrical activity in several regions = difficult to pinpoint
- post mortem, observed brain damages may not be linked to deficits during life times

ERP = display causation
- determine how processing = affected by specific experimental manipulation/stimuli