Cognitive Approach - Case Studies Flashcards
Milner (1966)
Background: HM had a temporal lobectomy to end his epileptic seizures which began after an accident. This resulted in him losing his hippocampus.
Aim: To determine the extent of HM’s memory deficiency.
Procedure: HM was initially studied by Brenda Milner, administering a range of tests and measures such as personality and mood tests, depression questionnaires, and interviews with psychiatrists. His scores did not indicate depression, anxiety or psychosis and he communicated a good awareness of his condition (i.e. he did not ‘forget’ that he was suffering from anterograde amnesia). He completed a standard IQ test on which his score was normal, however his scores on the Wechsler Memory Scale test demonstrated his severe memory impairment. Milner noted that HM frequently forgot what had happened that day, thought he was younger than his actual age, forgot the names of people he had just met and commented that every day felt as if he was just waking up from a dream. Milner studied him (and later, Corkin) for over 50 years until his death.
Conclusion/Results: The loss of his hippocampus meant that he could retrieve information from before the surgery, but he could not create new memories. He could, however, hold a conversation, showing that he had working STM memory. It appears that the hippocampus is responsible for transferring information from STM to LTM. This supports that there is more than one store for memory.
Peterson and Peterson (1959)
Aim: To investigate the duration of STM. (hypothesis being that information that is not rehearsed is lost quickly from STM).
Procedure: A lab experiment was conducted with 24 psychology students. They had to recall trigrams (meaningless three consonant syllables). The trigrams were presented one at a time and had to be recalled after intervals of 3, 6, 9, 12, 15, or 18 seconds respectively for each trial. No two successive trigrams contained any of the same letters. After hearing a trigram, participants were asked to count backwards in threes of fours from a specified random digit number until they saw a red light appear (then they recalled the trigram). This is known as the Brown Peterson technique, which aimed to prevent rehearsal. The Iv was the interval between hearing the experiment say the trigram and the participant recalling the trigram. The DV was the number of trigrams correctly recalled by the participant after every trial. There was six trials in total.
Results: Their results showed that the longer each student had to count backwards, the less well they were able to recall the trigrams accurately.
- After 3 seconds, 80% of the trigrams were recalled correctly
- After 6 seconds this fell to 50%
- After 18 seconds less than 10% of the trigrams were recalled correctly.
Bartlett (1932)
Aim: To investigate how the memory of a story if affected by previous knowledge. (Can previous knowledge lead to distortion of memory?)
Hypothesis: Memory is reconstructive and that people store and retrieve information according to expectations formed by cultural schemas.
Procedure: Told a number British participants a Native American legend called “The War of the Ghosts”. For the participants, the legend, the concept, the names, etc. were all unfamiliar due to cultural differences. This made the story ideal to study the reconstruction of memory based on schema processing. The participants were allocated to one of the two conditions: repeated reproduction (asked to reproduce the story after short time and then repeatedly over a period), and serial reproduction (recall and repeat to another person).
Results: It was found that there was no significant difference between the way that the groups recalled the story. Participants in both groups changed the story as they recalled, distortion. It was found that 3 patterns of distortion took place: Assimilation (changing details to fit the participants norms in their culture), leveling (shortening the story as participants omitted details that were seen as insignificant), and sharpening (change the order of the story to make sense of it and added details/emotions. Basically, they overall remembered the main themes but changed the unfamiliar elements to match their own cultural expectations so that the store remained a coherent whole although changed.
Conclusion: The study indicates that remembering is an active process, where information is retrieved and changed to fit into existing schemas. This is done in order to create meaning in the incoming information. According to this study, humans constantly search for meaning. Based on his research, Bartlett formulated the theory of reconstructive memory (meaning that memories are not copies of experiences but rather a reconstruction).
Shallice & Warrington - case study of KF (1974)
Aim: To determine the interaction between the biological cause of amnesia and its impact on memory.
Bacground: KF was in an accident and suffered memory impairment, he had brain damage to his left parietal and occipital lobe.
Procedure: A longitudinal case study using different memory tests including remembering both verbal and visual information.
Results: KF could transfer information from STM to LTM. He suffered problems with STM of different types of information: Auditory was effected but not memory of visual information.
Conclusion: The results support the Working memory model showing that STM is more complex than the multistore model of memory proposed.
Bransford & Johnson (1972)
Aim: To determine if schema activation would result in a better understanding and recall of an ambigous text.
Procedure: There was 52 ğarticipants allocated to one of three conditions. The “no topic” group, 17 participants heard a passage with no additional information. The “topic after” group, 17 participants were told the topic of the passage after hearing it. The “topic before” group, 18 participants were told the topic of the passage before hearing it. They were all told that they would later be asked to recall the passage as accurately as possible and they were tested at the same time. they were also asked to rate their comprehension of the passage on a 1-7 scale.
The researchers had decided on “idea units” before the experiment. Each participant2s summary was independently scored by two judges, using the list of 18 idea units.
Findings: The researchers concluded that “prior knowledge of a situation does not guarantee its usefulness for comprehension. For prior knowledge to aid comprehension, it must become an activated semantic context.”
Greene (2011)
Aim: To investigate whether forcing participants to wait before making a moral decision will cause system 2 rather than system 1 thinking to determine moral decisions.
Procedure: Participants are given a story morally wrong story and then two arguments (a strong and weak) supporting the story. They are asked to rate the morally acceptibility to the arguments after.
Results: When subjects got time to think, their system 2 thinking was activated and therefore a clear difference was seen in their responses as the strong argument would be more valid than the weak. When responses were given immediately, there was no differences in responses, supporting that they used system 1.
Cox & Criggs (1982)
Aim: to see if matching bias was less commonly used to solve the Watson Selection Task when the task was more personally relevant.
Procedure: The participants were 144 psychology students. They were randomly allocated to one of six groups in order to counterbalance the experiment. Each group was given a workbook with 3 problems and they all had a different order of the questions. Each problem had 4 cards and a statemnt and they were asked to turn over the cards that proved the statement incorrect. One of the tasks was not personally relevant and only consisted of letters and numbers, the other was more relevant, and the last one was highly personally relevant.
Results: It was found that:
- The Abstract task: 3% solved correctly
- Intermediate: 43% solved correctly
- Memory cueing task: 60% solved correctly
They also found that when the participants were given the abstract task first, there was an increase in the use of matching bias in the other conditions.
Conclusion: It appears that when the task cued memory of past experience, a more rational approach was taken to choosing the cards. The more abstract and less relevant the task, the more likely that cognitive biases would be used to solve the problem.
Tversky & Kahneman (1973)
Aim: To investigate the anchoring effect on judgements.
Procedure: Partcipants saw a picture of a sequence for 5 seconds and estimated its product. The sequence that was in descending order was the high anchoring condition and the sequence in ascending was the low anchor condition.
Results: Median estimate of produce in the high anchor group: 2250. Median estimate of product in ascending group: 512. The results imply that seeing the high numbers in the beginning had an effect in the participants estimate.
Englich & Mussweiler (2001)
Aim: To investigate if the smple request for a certain length of a prison sentence would unduly influence the decision made by a judge.
Procedure: An independent samples design was used (which allowed the researchers to use the same case study for both high anchor and low anchor conditions). The sample was made up of 19 young trial judges in order to control the level of courtroom experiences (average of 9 months of experience). The participants were given a case of alleged rape and the prosecutor in one condition demanded a sentence of 2 months vs. 34 months. The case materials were priorly tested on senior law students which served as a pilot study. the average recommended prison term suggested by the law students was 17 months, which was used as a basis for determining the anchors. Participants were given the case materials and asked to read through and form an opinion. Afterwards, they were given a questionnaire. Half of the participants were told that the prosecutor demanded 34 and the other half 2 month sentence. they were asked what they though of the recommendation, what they would recommend, how certain they were (1-9), and how realistic the case was (1-9).
Results: The average rating for the realistic nature of the case was 7.17, with a standard deviation of 1.3. The judges’ certain about their responses, however, was not as strong, with an average rating of 4.53 and a standard deviation of 2.29.
When presented with a low anchor, the average sentence was 18.78 months, with a standard deviation of 9.11. In the high anchor condition of 34 months, the average sentence was 28.70 months, with a standard deviation of 6.53.
Loftus & Pickrell (1995)
Aim: To determine if false memories of autobiographical events can be created through the power of suggestion.
Procedure: 24 participants. Before the study, a parent or sibling was contacted to ask to recall 3 childhood memories of the participant and if the participant had ever been lost in the mall. Then, the partiicpants recieved a questionnaire in the mail and asked about four memories and then mail back the questionnaire. Three events were real and one was “getting lost in the mall.” They were instructed if they didn’t remember the event, they should simply write “I do not remember this.” The particioants were interviewed twice over a month and asked to recall information about the four events. Then they were asked to rate their confidence (1-10). After the second interview, they were debriefed and asked if they could guess which one was the fake memory.
Results: About 25% of the particiapnts “recalled” the false memory. However, they also ranked this memory as less confident than the other memories and they wrote less about the memory.
Loftus & Palmer (1974) - study 1
Background: participants were shown videos of traffşc accidents and after, they had to answer questions about thw accident. They were asked about the speed of the car in different ways. For example, “About how fast the cars were going when they smashed/hit each other?” This was based on the assumption that these words would have different connotations and activate different cognitive schemas about the severity of the accident.
Aim: To investigate whether the use of leading questions would affect the estimation of speed.
Hypothesis: “Smash” results in a higher estimation than “hit”.
Procedure: 45 students participated and divided into 5 groups of nine students. Seven films of traffic accidents wers hown and the length of the films ranged from 5 to 30 seconds. The study was an independent samples design: each participant watched all 7 films.
When the participants had watched a film, they were asked to give an account of the accident and answer a questionnaire with different questions on the accident with one being the critical question. They were asked the same question but it included different words.
Results: The mean estimated of speed were highest in the “smashed” condition and lowest in the “contacted” condition.
Conclusion: The results indicate that the critical word in the question consistently affected the participants’ answer to the question. The researchers argued that it may be that the different estimates were a result of the the response bias (uncertain so the word biases their response). It may also be that the way the question is formed results in a change in the particioant’s mental representation off the accident. The distortion of memory is based on the reconstruction so that it is not the actual details of the accident that are remembered but rather what is in line with a cognitive schema of a severe accident. This interpretation is in line with Bartlett’s suggestion of reconstructive memory due to schema processing.
In conclusion, it seems that participants’ memory of an accident could be changed by using suggestive questions.
Loftus & Palmer (1974) - study 2
Background: In order tı investigate if the differences in speed estimation in the first study was due to the form of the question (schema processing), the researchers performed a second experiment.
Aim: To investigate if participants who had high-speed estimate in the first part of an experiment would say that they had seen broken glass in the second part of the experiment. The researchers hypothesized this would happen.
Procedure: 150 particioants randomly allocated to conditions. They were shown a 1-minute film depicting multiple car accidents lasting around 4 seconds. After, they answered a questionnaire wtht he same critical question with the variations: “About how fast were the cars going when they smashed/hit each other?” and the remaining 50 was not asked a speed estimate.
After one week, the participants came back and answered more questions. The one critical question this time in a list of 10 different questions was “Did you see any broken glass?” with the options “yes” or “no”. There was no broken glass in the accident.
Results: The mean estimate of speed by the participannts who had “smashed” was 10.46 mph and the “hit” group 8.00 mph. In the “smashed” condition, 16 participants said “yes” to the broken glass question in comparison to 7 in the “hit” condition. Although most participants accurately reported no glass, more of the participants in the “smashed” condition said “yes”.
Conclusion: It was argued that the results of the second experiment provided further support for the theory of reconstructive memory and schema processing.
McGaugh & Cahill (1995)
Aim: To study the role of emotions on the creation of memories.
Procedure: Participants were divided into group and saw different stories. There was a neutral condition (mother and son who went to see father in the hospital where they saw a disaster preperation drill), and an emotionally arousing condition (a boy involved in a car accident with feet severed and spent weeks in a hospital). 2 weeks later they were asked to return and their memory for specific details was tested in the form of recognition task with a series of questions with 3 possible answers.
Follow-up study: the study was repeated, but the participants that heard the emotionally arousing story were given a beta-blocker called propranolol (interferes with the release o adrenaline and used to prevent amygdala activation) whilst others were given placebo.
Findings: Original study: Participants who heard the more traumatic story demonstrated better recall of specific details and more overall details.
Follow-up study: Those that recieved beta-blockers did no better than the other group.
Conclusion: Amygdala plays a significant role of the creation of memories linked to emotional arousal due to adrenaline.
Kulkofsky (2011)
Aim: To investigate the role of culture on FBM in five countries: China, Germany, Turkey, the UK, and the USA
(If there was any difference in the rate of flashbulb memories in collectivistic and individualistic cultures).
Procedure: First, the participants were given five minutes to recall as many memories as they could of public events (occurring at least one year ago in their lifetime)
The researchers then used this list of events to create a ‘memory questionnaire’
They were asked five questions about reception context (how they learned about the event; mirrored the original questionnaire used by Brown and Kulik in 1977). They were then asked to answer questions about the importance of the event to them personally (personal relevance)
The survey instructions were constructed in English and then translated and back-translated into the native languages of the countries investigated by bilingual researchers (to ensure that translation was not a confounding variable)
Results: The researchers found that in collectivistic cultures like China, personal importance and intensity of emotion played less of a role in predicting FBM in comparison to individualistic cultures (like the UK) that place greater emphasis on an individual’s personal involvement and emotional experiences however, it was found that national importance was equally linked to FBM across cultures.
Conclusion: In individualistic societies, an individual’s emotions are considered part of his/her uniqueness (sharing memories is also a valuable social practice)
In collectivistic societies, there is a tendency for lower levels of emotions, lower levels of mental ruminations, and less social sharing of emotions. Therefore, self-expression is inhibited in collectivistic cultures because focusing on the individual’s own experiences is often de-emphasized in the Chinese context, there would also be less rehearsal of the triggering event and thus a lower chance of developing a FBM compared with people from other cultures
