Brain Investigations

Question 1

FMRI

Answer 1

• Functional magnetic resonance imaging
• detects changes in the blood oxygenation and flow that occur as a result of neural activity in specific parts of the brain
• when its more active it consumes more oxygen, and to meet demand more blood flow is directed to the active area (haemodynamic response)
• produces 3D images
• shows which parts of the brain and involved in particular mental processes

Question 2

Strength of FMRIs

Answer 2

• doesnt rely on the use of radiation
• virtually risk free and non-invasive
• produces images with very high spacial resolutions, depicting details by millimetre
• clear picture on how brain activity is localised

Question 3

Limitation of FRMIs

Answer 3

• very expensive compared to others
• can only capture clear image if person stays perfectly still
• poor temporal resolution due to 5 second time lag
• can only measure blood flow, can’t focus on specific neurons
• difficult to tell what kind of activity is being presented on the screen

Question 4

EEG

Answer 4

• electroencephalogram
• measures brain activity via electrodes that are fixed to a scalp using a skull cap
• represents brainwave patterns generated from millions of neurons
• diagnostic tool -> epilepsy, tumours, sleep disorders

Question 5

Strength of EEG’s

Answer 5

• invaluable diagnosis of conditions such as epilepsy
• helped understand the different stages of sleep
• high temporal resolution
• detects brain activity at the resolution of a millisecond

Question 6

Limitation of EEGs

Answer 6

• generalised nature of the information received
• not useful for pinpointing exact source of neural activity
• doesn’t allow researchers to distinguish between activities originating in different, but adjacent locations

Question 7

ERPs

Answer 7

• overly general measure of brain activity
• types of brainwave that are triggered by a particular event
• how they’re linked to cognitive processes such as attention and perception

Question 8

Strength of ERPs

Answer 8

• bring much more specificity to the measurement of neural processes that could ever be achieved using raw EEG data
• describe precise role of cognitive functioning
• maintenance of WMM

Question 9

Post-mortem

Answer 9

• analysis of persons brain following their death
• rare disorder, unusual deficit in mental processes, or behaviour in their lifetime

Question 10

Limitation of post-mortem

Answer 10

• issue of causation
• deficits reported could have been a result of another illness, and would be unable to conclude that the deficit is caused by the damage found in the brain
• ethical issues

Question 11

Strength of post-mortem

Answer 11

• detailed examination of the anatomical structure and neurochemical aspects of the brain that isnt possible with other scanning techniques
• can access areas like hypothalamus and hippocampus whilst others cannot
• provides an insight into deeper brain regions