case study: HM

Question 1

what is a case study?

Answer 1

• a detailed study of one case - but case could be one person, one group of people or event

Question 2

how long can case studies be conducted?

Answer 2

• within a short amount of time or may follow the case over many years

Question 3

what kind of data do case studies collect?

Answer 3

• qualitative data
• this is to get required depth and detail
• however, if appropriate tests and experiments are carried out and these give quantitative data (e.g. iq test may be carried out)

Question 4

what is triangulation?

Answer 4

• gathering data using different research methods (e.g. observation and interview) and developing themes
• if information from both sources are similar then they reinforce each other and increase reliability

Question 5

strengths of case studies

Answer 5

• can be used to instances of human behaviour and experiences that are rare (e.g. mental illness) or cases which could not possibly be created in research labs (e.g. cases of damage to specific areas of brain)
• produces rich, in-depth data because complex interaction of many factors can be studies in contrast with experiments where variables are help constant. this means that information that may be overlooked using other research methods can be researched. case study methods are important for psychologists who adopt holistic approach

Question 6

weaknesses of case studies

Answer 6

• difficult to generalise from individual cases as each other has unique characteristics and as we can’t make before-after comparisons
• often necessary to use recollection of past events as part of case study. such evidence may be unreliable because people’s memories are innacurate
• researchers may lack objectivity as they get to know case, or because their theoretical biases may lead them to interpret data less objectively
• important ethical issues such as confidentiality and anonymity. many cases are easily identifiable because of unique characteristics, even when real names are not given.

Question 7

brain-damaged patient: KF

Answer 7

• by Shallice + Warrington 1972
• young man who had motorbike accident aged 17 causing blood clot in brain and required surgery left him with damage in left parietal-occipital cortex
• age 19 developed epilepsy
  age 28 tested by psychologists who found he had overall iq of 113 but verbal iq of 79
• memory of daily and past events good
• almost totally unable to repeat verbal stimuli
• digit span was only one digit or letter
• visually presented numbers and letters did not present KF with same difficulties and his digit span was around three to four

Question 8

what does KF case study show?

Answer 8

• stm and ltm are separate as proposed by msm
• at least two types of stm - verbal and visual. shows that msm is far too simple as it only shows one store of stm. supports Baddeley + Hitch’s wmm which divides stm into verbal and visual components - phonological loop and visuospatial sketchpad

Question 9

brain-damaged patient: Clive Wearing

Answer 9

• severe brain infection causing extensive damage including hippocampus. this left him with severe amnesia
• unable to form new memories and has memory of only 30 secs
• no memory of his life before brain damage except love for his second wife who he greets joyously every time they meet
• can play piano showing procedural memory is intact
• learn new skills and few facts through procedural memory e.g. by watching a video repeatedly

Question 10

what does case of CW show?

Answer 10

• stm and ltm are separate proposed by msm. cw only has stm, and cannot form new ltm. unlike HM, he has no ltm from before illness, showing that brain damage was more extensive and ltms are encoded in hippocampus but stored in cortex
• three types of ltm - semantic, episodic and procedural. episodic must be encoded using hippocampus but procedural is not. semantic can survive damage to hippocampus and cortex. shows that msm is far too simple as it just shows one store for ltms
• emotional memories are also separate from episodic and can remain intact when hippocampus is damaged, suggesting they are linked to deeper structures like amygdala

Question 11

brain-damaged patient: HM

Answer 11

• suffered from severe epilepsy
• surgeon decided that removing tissue from hippocampus could cure epilepsy
• 1953 age 27 two-thirds of his hippocampus and adjacent structures were removed in surgery, leaving only 2cm of hippocampus which was described as entirely non-functional
• successfully cured epilepsy but left HM unable to form any episodic memories
• had anterograde: loss of ability to make new memories and retrograde: loss of ability to recall events prior to injury
• extensively studied throughout his life
• unable to live independently
• HM was able to learn new motor skills (despite not remembering what he had) and so could form new procedural memories

Question 12

who was HM referred to?

Answer 12

• neuropsychologists Wilder Penfield and Branda Milner

Question 13

what does case of HM show?

Answer 13

• stm and ltm are separate as proposed to msm
• three types of ltm - semantic, episodic and procedural. episodic memory must be encoded using hippocampus but procedural memory is not. shows that msm is far too simple as it shows just one store for ltm
• HM could retrieve some memories from before surgery - encoding and retrieval in ltm must use different systems and brain areas