Case Studies Flashcards
(15 cards)
General description of a case study
- in depth, detailed investigation
- on an individual or a small group of people
- generally conducted on rare or unique individuals
- e.g. those who have suffered trauma to the brain
- allows researchers to study damage/cognitive dysfunctions which would be unethical to create
Features of a case study
- have a longitudinal design- over many years
- gather both quantitative and qual data (mainly qual)
- qual data= describing what functioning is intact or lost as a result of amnesia to understand the patients subjective experiences
- many sources of information- e.g. psychometric testing, interviews, observations, cognitive tests)
- allows for triangulation of data
- qual analysis is idiographic- aims to explore unique aspects of a persons experience, behaviour and development
- case history must be established- academic records to assess IQ, medical records, friends and family interviewed to ask about personality.
- naturalistic study- brain damaged patient to assess effects of brain damage on memory functioning
Background on HM
- HM was a case study
- underwent a hippocampus removal to treat his severe seizures
- led to him developing profound anterograde amnesia- could not form new LTM, and retrograde amnesia- loss of memories
- Milner (1966) studied him for over 50 years.
- aged 27 at start of study
- o.g. Case study involved 9 patients, but H.M was the only one with clean amnesia- no other mental/comorbid symptoms
Procedure of H.M.
- conducted investigation using multiple methods (triangulation of data)
- at the start- involved simple recall tasks- from childhood, adult life before op and experiences from after the op.
- also tested stm + LTM, and other cognitive faculties like IQ, perception and general knowledge.
- two types of tasks- star task and the maze task
- maze task= H.M had to trace the correct route through he maze with is finger- and then was tested over and over with the same maze to see if HM would remember the route
- star task= had to copy a 5-pointed star, could only see the reflection of the star and had to draw between the lines of a template, re attempted the task many times.
- other tests such as the effect of reinforcement and punishment was later investigated to see if the effect of mild shocks would help H.M remember correct answers
Results of H.M
- after 252 attempts, H.M never showed any improvements in the maze task many times
- H.M did show improvement in the star tracing task- making fewer mistakes on each attempt- starting with 30 errors and dropping to 20 on his second attempt, 10 by his seventh
- he kept showing signs of improvement- by day 2, he only may 25 mistakes and by day 3, he made fewer tan 5 mistakes each time.
- h.m forgot all new experiences after 30 seconds
- personality consistent, good language skills and an above-average IQ
- could describe clear memories of his childhood- could recall events before his 16th birthday
- lacked context for this events- e.g how long ago they happened
- had a knowledge of past events such as the Wall Street Crash and WW2.
- could not remember where he lived, who cared for him or what he ate for his last meal.
- he did acquire some knowledge from after his operation- he knew what an astronaut was, that someone named Kennedy was assassinated and what rock music was
- he learnt how to play tennis and improved on star task= procedural memory
Conclusions from H.M
- qual data shows clear difference between stm and ltm
- suggests that the hippocampus plays a vital role in transforming between stm-ltm
- suggested the existence of three separate stores of LTM
- episodic, semantic, procedural
Description of naturalistic study
- patient is assessed in their home environment
- this is to assess everyday functioning
What is the longitudinal design?
- study brain damaged patients over a long period of time
- to assess decreases/improvements in memory functioning
- to track the effectiveness of a treatment over time
- h.m studied for 50 years
Describe multiple methods used
- observations- to gather qualitative data
- can include the ability to perform everyday tasks, frequent forgetting, general skills
- interviews to assess stm and ltm e.g the recall of childhood memories and descriptions of behaviour
- questionnaire to assess general memory performance
- psychometric testing- to assess personality, IQ, and establish general skills.
Qualitative data analysis- idiographic etc
- there is no general rules about qual analysis
- idiographic= focussing on understanding unique behaviour in depth- rather than seeking general laws
- once gathered, transcriptions are made- the researcher immerses themselves into this text
- make notes of feelings, beliefs and meanings given to experiences by patients
- researcher reflects on these notes and checks that they reflect the content of the transcript
- develops from these notes the emerging themes
- themes are presented as conclusions with extracts from the transcript to support their interpretation
- qual analysis gathers rich description based on meaning- which can be limited using quant data
- follows no standardised format - unscientific and highly subjective
Generalisability
A weakness of case studies is that there are very low levels of generalisability. For example a case study of an individual person such as H.M with brain damage may not be representative of anyone else- as each case of brain damage has a unique context- and so experiences are so individual that another person may not react in the same way. Therefore, this is a problem, as it lacks generalisability to the rest of the population as each case has unique characteristics and so is therefore not representative.
Reliability
A weakness of a case study is that it lacks reliability. This is because it gathers qualitative data, and takes an idiographic stance on analysis of experiences- it aims to understand the individuals experiences and their symptoms as a result of brain damage- not the general rules that apply to other people. Therefore, analysis of the interviews which are conducted or the observations which are gathered by researchers of an individual such as H.M who had his personality tested and stm/ltm are highly subjective to the researcher as they follow no standardised format or procedure. This cannot therefore be repeated to check for consistency within results, which reduces the reliability. However, case studies may be the only ethical way of investigating such brain damage. Cases such as H.M which left him with a memory of 30 seconds- retrograde and anterograde amnesia, and so this would be highly unethical to repeat on another patient to check for consistency within results- and so studying H.M following his operation as treatment for seizures may be the only ethical way to study such brain damage- and provide insights into how brain damage to the hippocampus can lead to cognitive dysfunction in memory.
Applications?
There are positive applications to case studies. Studying individuals such as H.M for over 50 years has led to the suggestion of a new type of memory model for LTM- tulvings theory of ltm. This explains H.Ms symptoms, by proposing the idea of semantic and episodic memories- memories of general knowledge and memories of events. This can explain why he could remember certain memories such as the Wall Street crash and ww2 as they are strong semantic memories which have a very strong memory trace, but not episodic memories following his 16th birthday- as they have a weaker memory trace. Therefore, case studies can benefit psychologists in explaining human behaviour by providing solutions for police to use in interviews such as contextual reinstatement- so that retrieval cues can be used.
Validity
A weakness of case studies is that they involve qualitative data. This is highly subjective and risks the chance of misinterpretation or researcher bias. Therefore reduces validity. However, it uses triangulation- there are multiple different methods of data collection used- involving quant and qual data, which allows for the increased accuracy of findings etc.
case study must be constructed- involves retrospective data. E.g the researcher might rely on asking friends and family about their past such as about their personality, memory abilities and general health, which can be reconstructed. This is a problem as such evidence may have been recalled inaccurately and may therefore be unreliable, decreasing internal validity
Ethical considerations
A strength of case studies is that it is more ethical than lab studies. For example psychologists can research rare and sensitive topics such as hoe patients experience brain damage and how impacts their long term health and memory. These questions could not be addressed by giving them a questionnaire or testing their functioning in a lab- as they would be vulnerable to getting harmed in a lab study. Additionally, it allows researchers to study illnessses or brain damage in an ethical way- following a traumatic event naturally occurring to them. The researcher does not deliberately cause such damage which would be highly unethical and go against a psychologists duty of care, and so is the only ethical way to investigate the effects of brain damage on memory abilities.
