Biopsychology year 2 P2 // Ways of studying the brain

Question 1

explain what is meant by a fMRI scan?

Answer 1

detects when area of the brain becomes more active - uses more oxygen so blood flow increases to that area bringing more oxygen with it - presented by colours, red = active.

Question 2

what are two strengths of using fMRI scans?

Answer 2

1. does not expose patient to harmful radiation

2. produces objective, precise and reliable measures of the brain activity.

Question 3

what are two weaknesses of using fMRI scans?

Answer 3

1. cannot identify individual neurons so it cannot exactly show what brain activity is taking place
2. lag time of 5 seconds between initial fire of neurons and image appearing on screen - does not provide an immediate record of brain activity.

Question 4

explain what is meant by a EEG?

Answer 4

records electrical activity of brain, electrodes placed over scalp and produced different wave patterns on screen.

Question 5

what are two strengths of using EEGs?

Answer 5

1. records brain activity as it happens - no lag time

2. helps diagnose conditions such as epilepsy and understanding of brain activity in the stages of sleep.

Question 6

what are two weaknesses of using EEGs?

Answer 6

1. only gives a generalised picture of what is happening - cannot differentiate between areas next to each other.
2. only detects activity in outer layers of brain. cannot reveal much about the hypothalamus or hippocampus.

Question 7

what is meant by a event related potential (ERP) scan?

Answer 7

same method as EEG but able to pinpoint activity in response to a specific stimuli or event.

Question 8

what are two strengths of using ERPs?

Answer 8

1. no lag time so more successful in investigating cognitive processes
2. can assess brain activity without an individual open having to give a response, valuable when socially sensitive or social desirability bias may be a issue.

Question 9

what are two weaknesses of using ERPs?

Answer 9

1. not easy to pick out responses, researcher has to carry out lots of repeated trials, limits the validity of investigation.
2. can only show limited types of brain activity -deeper brain activity cannot be detected by the voltage.

Question 10

what is meant by a post mortem examination?

Answer 10

investigate brain activity after death in an individual that has shown unusual behaviour during their life. e.g. HM had damage to his hippocampus that affected his memory.

Question 11

what are two strengths of post mortem examinations?

Answer 11

1. can access deeper levels of the brain like the hippocampus and hypothalamus
2. have extended understanding into abnormal behaviours.

Question 12

what are two weaknesses of post mortem examinations?

Answer 12

1. damage to areas of the brain seen may be caused by the death of the individual not the experiences they had
2. ethical issue - dead person cannot give informed consent e.g. HM.