PAPER 2 - BIOPSYCHOLOGY - ways of studying the brain

Question 1

what are the 4 ways of studying the brain?

Answer 1

• post-mortem examinations
• fMRI
• electroencephalograms (EEG)
• event related potentials (ERPs)

Question 2

what is a post mortem examination?

Answer 2

• used to establish the neurological cause of behaviour
• used to look for brain abnormalities after death, and areas of brain damage
• makes it possible to identify some of the brain structures involved in memory

Question 3

what is fMRI?

Answer 3

• measures blood flow and oxygen, shows increased neural activity in specific areas while person is performing a task
• allows researchers to identify which areas of the brain are involved in particular mental activities

Question 4

what are EEGs?

Answer 4

• records changes in electrical activity of the brain using electrodes on scalp
• detects various types of brain disorder or to diagnose other disorders (e.g. Alzheimer’s shows slow activity of brain)

Question 5

what are ERPs?

Answer 5

• measures small voltage changes in the brain triggered by specific events or stimuli/cognitive activity
• more detailed way of studying specific responses to stimuli than EEG
• “sensory ERPs” occur within first 100ms after stimulus presentation, “cognitive ERPs” are generated after this time

Question 6

what are the strengths of fMRI?

Answer 6

• noninvasive, doesn’t expose brain to harmful radiation
• offers more objective and reliable measure of physiological processes than possible with verbal reports

Question 7

what are the limitations of fMRI?

Answer 7

• measures changes in blood flow so isn’t a direct measure of neural activity in particular areas, not truly a quantitative measure of mental activity
• fMRI overlooks the networked nature of brain activity, as it focuses only on localised activity in the brain

Question 8

what are the strengths of EEG?

Answer 8

• provides recording of the brain’s activity in real time rather than still image of passive brain
• useful in clinical diagnosis e.g. recording abnormal neural activity associated with epilepsy

Question 9

what are the limitations of EEG?

Answer 9

• detects activity in superficial regions of the brain, it cant reveal what’s going on in deeper regions e.g. hypothalamus
• electrical activity can be picked up by several neighbouring electrodes so hard to pin point exact source of activity

Question 10

what are the strengths of ERP?

Answer 10

• provide a continuous measure of processing in response to a particular stimulus, makes it possible to determine how processing is affected by experimental manipulation
• can measure processing of stimuli in absence of behavioural response

Question 11

what are the limitations of ERP?

Answer 11

• small and difficult to pick out from other electrical activity in the brain, so requires large trials to gain data
• only sufficiently strong voltage changes generated across the scalp are recordable, recordings restricted to neocortex

Question 12

what are the strengths of post-mortem exams?

Answer 12

• more detailed examination of anatomical and neurochemical part of the brain than fMRI and EEG
• claims that post-mortem exams have played central part in understanding of schizophrenia, helps discover neural abnormalities in neurotransmitter system

Question 13

what are limitations of post-mortem exams?

Answer 13

• people die in variety of circumstances, these factors can influence the post-mortem brain
• length of time between death and post-mortem, drug treatments and age at death can influence brain
• retrospective as person is already dead, researcher is unable to follow anything up concerning relationship between abnormalities and cognitive functioning