The Cognitive Level of Analysis
Introduction
Cognitive science is the interdisciplinary scientific study of the mind and its processes. It examines what cognition is, what it does and how it works. It includes research on intelligence and behaviour especially focusing on how information is represented, processed, and transformed (in faculties such as perception, language, memory, reasoning, and emotion) within nervous systems (human or other animal) and machines (e.g. computers).
The three main ideas of the Cognitive Level of Analysis;
1. People are active information processors. They perceive and interpret what is going on around them. This is often based on what they already know. There is a relationship between people's mental representation and the way people perceive and think about the world.
2. Cognitive researchers use a number of scientific methods to study the mind (e.g. laboratory experiments, neuroimaging, case studies, interviews and archival research). The most used research method was, for a long time, the laboratory experiment, because it was considered to be the most scientific.
3. Research has shown that cognitive processes such as perception, memory, and thinking are influenced by sociocultural factors.
Cognitive science is the interdisciplinary scientific study of the mind and its processes. It examines what cognition is, what it does and how it works. It includes research on intelligence and behaviour especially focusing on how information is represented, processed, and transformed (in faculties such as perception, language, memory, reasoning, and emotion) within nervous systems (human or other animal) and machines (e.g. computers).
The three main ideas of the Cognitive Level of Analysis;
1. People are active information processors. They perceive and interpret what is going on around them. This is often based on what they already know. There is a relationship between people's mental representation and the way people perceive and think about the world.
2. Cognitive researchers use a number of scientific methods to study the mind (e.g. laboratory experiments, neuroimaging, case studies, interviews and archival research). The most used research method was, for a long time, the laboratory experiment, because it was considered to be the most scientific.
3. Research has shown that cognitive processes such as perception, memory, and thinking are influenced by sociocultural factors.
The Outline
3.1 The principles of the cognitive level of analysis:
· The mind can be studied scientifically – Corkin et al. (1997)
· Humans are information processors and mental processes guide behaviour – Atkinson and Shiffrin (theory) and Glanzer and Cunitz (1966)
· Cognitive processes are influenced by social and cultural factors – Bartlett (1932)
How and why particular research methods are used in the cognitive level of analysis
· Lab experiments – (able to control variables) Loftus and Palmer (1974)
· Lab experiments – (able to look at the brain) Corkin et al. (1997)
Ethical considerations linked to the cognitive level of analysis
· Consent/Withdraw – Clive Wearing (born 1938)
3.2 The Schema theory
· Bartlett (1932)
· DiMaggio (1997)
. Darley and Gross (1983)
3.3 Two models of memory
· Atkinson and Shiffrin – the multi-store model of memory (1968)
· Baddeley and Hitch – the working model of memory (1974)
3.4 Explain how amnesia may affect memory
· Scoville and Milner (1957)
· Corkin et al. (1997)
3.5 Cultural factors influencing memory
· Bartlett (1932)
· Wang and Ross (2007)
· Cole and Scribner (1974)
3.6 Reliability of memory
· Bartlett (1932)
· Loftus and Palmer (1974)
· Riniolo et al. (2003)
3.7 Explain technology in investigating cognitive processes
· Corkin et al. (1997)
3.8 Explain how cognitive and biological factors interact with emotion
· LeDoux (1999)
· Phelps (2004)
· Lazarus (1975)
· Speisman et al. (1964)
· LeDoux (1975)
3.9 Explain how emotion may affect memory
· Brown and Kulik (1977)
· Neisser and Harsch (1992)
· The mind can be studied scientifically – Corkin et al. (1997)
· Humans are information processors and mental processes guide behaviour – Atkinson and Shiffrin (theory) and Glanzer and Cunitz (1966)
· Cognitive processes are influenced by social and cultural factors – Bartlett (1932)
How and why particular research methods are used in the cognitive level of analysis
· Lab experiments – (able to control variables) Loftus and Palmer (1974)
· Lab experiments – (able to look at the brain) Corkin et al. (1997)
Ethical considerations linked to the cognitive level of analysis
· Consent/Withdraw – Clive Wearing (born 1938)
3.2 The Schema theory
· Bartlett (1932)
· DiMaggio (1997)
. Darley and Gross (1983)
3.3 Two models of memory
· Atkinson and Shiffrin – the multi-store model of memory (1968)
· Baddeley and Hitch – the working model of memory (1974)
3.4 Explain how amnesia may affect memory
· Scoville and Milner (1957)
· Corkin et al. (1997)
3.5 Cultural factors influencing memory
· Bartlett (1932)
· Wang and Ross (2007)
· Cole and Scribner (1974)
3.6 Reliability of memory
· Bartlett (1932)
· Loftus and Palmer (1974)
· Riniolo et al. (2003)
3.7 Explain technology in investigating cognitive processes
· Corkin et al. (1997)
3.8 Explain how cognitive and biological factors interact with emotion
· LeDoux (1999)
· Phelps (2004)
· Lazarus (1975)
· Speisman et al. (1964)
· LeDoux (1975)
3.9 Explain how emotion may affect memory
· Brown and Kulik (1977)
· Neisser and Harsch (1992)
The Studies Relevant to the CLOA
Studies in the Cognitive Level of Analysis
Corkin et al. (1997)
He used MRI scans and analysed the extent of the damage to H.M’s brain. The scans showed that temporal lobes including the hippocampus and related structures on both sides were missing. This part of the brain’s memory system plays a crucial role in transforming short-term memories into long-term memories.
These areas are involved in specific neurotransmitter pathways in memory (e.g. acetylcholine is believed to play an important role in learning and episodic memories).
Atkinson and Shiffrin (1968)
Models of Memory: they are primitive diagrams of human memory to help understand the flow of information and how it is stored.
Model 1: The multi-store model of memory (Atkinson and Shiffrin, 1968)
Glanzer and Cunitz (1966)
Aim: to investigate recency effect in free recall (i.e. in any order)
Procedure: this was a laboratory experiment where participants first heard a list of items and then immediately had to recall them in any order.
Results: participants recalled words from the beginning of the list (primacy effect) and the end of the list (the recency effect) best. The results showed a U-shaped curve. If participants were given a filler task just after hearing the last words, the primary effect disappeared but the recency effect remained.
The recency effect could be due to the words still being active in STM (working memory). Rehearsal could be a factor in the transfer of information into LTM.
Evaluation: the study supports the idea of multiple stores (STM and LTM). This is a controlled laboratory study with highly controlled variables, but there is no random allocation of participants to experimental conditions so it is not a true experiment. There may also be problems with ecological validity.
Bartlett (1932)
Aim: to investigate whether people’s memory for a story is affected by previous knowledge (schemas) and the extent to which memory is reconstructive.
Procedure: Bartlett asked British participants to hear a story and reproduce it after a short time and then repeatedly over a period of months or years (serial reproduction). The story was an unfamiliar Native American legend called “The War of Ghosts”.
Results: The participants remembered the main idea of the story but they changed unfamiliar elements to make sense of the story by using terms more familiar to their own cultural expectations. The story remained a coherent whole although it was changed.
Conclusion: remembering is an active process and are not copies of experience but rather “reconstructions”
Strengths vs. Weaknesses: The weaknesses in this study were ethical considerations that were breeched but this is one of the most famous studies for the learning of memory.
Ethical Considerations: this study was performed in a laboratory and can be criticized for the lack of ecological validity. Participants did not receive standardized instructions and some of the memory distortions may be due to participants’ guessing.
How did the study add to our understanding of schemas and their role in memory?
Bartlett’s theory was unfashionable for many years but has recently been recognised as providing a valuable insight into the reconstructive nature of human memory. His theory was based on Western recall of a native North American folk story. He suggested that we make the following alterations in such cases:
Darley and Gross (1983)
Aim: to investigate whether a schema or pre-exisiting idea will make people form stereotypes for a particular person
Procedure: participants were told that a girl called Hannah was either rich or poor. The people that were told she was rich split off into a separate group to those that were told she was poor. Both groups watched exactly the same video about her.
Results: participants in the "wealthy family" group rated Hannah's performance above fourth grade, whereas the "poor family" group rated her performance below fourth grade, in spite of watching the same ambiguous video.
Conclusion: these findings demonstrate that stereotypes about socioeconomic status affect perceptions of intelligence.
Strengths vs. Weaknesses: are the results really reliable.
Loftus and Palmer (1974)
Aim: to investigate how information is supplied after a particular event and how it influences a participant’s memory. They wanted to see if changing a verb in a series of critical questions would influence their opinion about a car crash.
Hypothesis: they predicted that by changing the verb in a critical question, they would be able to manipulate the participants’ memory of a car accident.
Research Method: laboratory experiment
Independent variable (IV): The verb that was changed in the critical question for both experiments
Dependent variable (DV): 1st experiment; the participants estimate of speed that the car was going at
2nd experiment; whether the participant believed they saw glass in the car accident
Sampling method and characteristics of participants: The first experiment used 45 students who were all from the University of Washington (volunteer sampling and chosen so that there would be similar results. The second experiment used 150 participants (random sampling but all from US still)
Procedure: The first experiment consisted of seven film clips of traffic accidents that were shown to the participants. Following each clip, the students were asked to write an account of the film they just watched and answer questions, including the critical question; the speed of the vehicles involved in the accident. There were five different questions given to different people, they were all the same but the verb changed.
For example:
Condition 1: 'About how fast were the cars going when they smashed into each other?'
Condition 2: 'About how fast were the cars going when they collided into each other?'
Condition 3: 'About how fast were the cars going when they bumped into each other?'
Condition 4: 'About how fast were the cars going when they hit each other?
Condition 5: 'About how fast were the cars going when they contacted each other?'
The idea was that participants would change their view depending on the condition they got
The second experiment provided a slightly different insight into the origin of the different speed estimates. In particular they wanted to discover whether the verbal label had really distorted the participants’ memories. There watched a final clip of a multiple car accident and there were three conditions and again a verb was manipulated in the critical question.
50 of the participants were asked 'How fast were the cars going when they hit each other?’
50 of the participants were asked 'How fast were the cars going when they smashed into each other?'
50 of the participants were not interrogated about the speed of the vehicles.
One week later the participants were asked to return and without showing any clips, they were asked to answer a series of questions. The critical question was 'Did you see any broken glass?' The critical question was part of a longer series of questions and was placed in a random position on each participants question paper but there was no broken glass in the film.
Results and conclusions:
The interpretation of the results was that the use of different verbs activates different schemas in memory, so that the participant hearing the word “smashed” may actually imagine the accident as more severe than a participant hearing the word “contacted”. Also the researches explained that “smashed” provides the participants with verbal information that activates schemas for a severe accident. Broken glass is in line with this, so the participant is more likely to think that there was broken glass involved.
How did this study contribute to understanding human behaviour?
Loftus’s research indicated that it is possible to create a false memory using post-event information. This helps to understand human behaviour in every-day situations and help understand that eyewitnesses may not remember something in exactly the same way if there is a manipulated situation.
Strengths and Limitations of the methodology:
Strengths are that this experiment allowed for a control of variables. The purpose of being able to control an experiment is so that one can isolate the one key variable, which has been in, selected in order to observe its effect on another variable. This is therefore easier to conclude from. For example the researchers were able to control the age of the participants, the use of video and the location of the experiment.
The limitations of this method were that the experiment was not typical of a real life situation and were held in a laboratory, so wouldn't be how people would normally witness events. They had no personal involvement in the judgement and weren't actually in the event of the car accident. Normally when people witness events in everyday life, people often have some involvement in the action, therefore it is hard to generalise findings from laboratory experiments because they are not ecologically valid.
Another problem with the study was the use of students as the participants as they are not representative of the whole population. They also may be less experienced drivers and therefore less confident in estimating speeds. This may have influenced their answer in the critical questions.
Gender and Cultural Considerations:
All the participants were US students, which mean that the sample was culturally biased.
Ethical Considerations:
Ecological validity as the study was held in a laboratory.
HM
Background information
Henry Molaison (HM) is a famous memory disorder patient whose hippocampus, parahippocampal gyrus, and amygdala were surgically removed whilst trying to cure his epilepsy. For this reason, he suffered awful memory conflicts and was therefore studied for the majority of his life. Following the surgery HM was unable to form any new long-term memories (anterograde amnesia) and couldn’t retrieve some of his existing long-term memory (retrograde amnesia). However, his short-term memories remained regular, limited only by HM’s inability to rehearse. When HM underwent the surgery, William Scoville removed both of his temporal lobes including a structure known as the hippocampus and an area known to be crucial to memory. HM survived the operation and his epilepsy became less damaging; however he now had to go through life suffering from retrograde and anterograde amnesia.
Why is this case study so significant?
This case study has provided a large amount of insight into how important the hippocampus and other regions of the brain are so vital for your memory. H.M. was able to retain some memories for events that happened long before his surgery. This indicates that the medial temporal region with the hippocampus is not the site of permanent storage in itself. It rather seems to play a role in how memories are organised and then stored somewhere else in the brain.
It has presented opportunities that researchers never could have discovered if it wasn’t for the mishap in surgery. As psychologists cannot damage a person’s hippocampus on purpose, just to study memory effects, psychologists owe a lot of gratitude to HM as it has helped them to study the outcomes of someone with intense amnesia.
Clive Wearing (born 1938)
Background information
Clive Wearing was a musician that was in his mid-forties, when suddenly he was struck by a brain infection known as herpes encephalitis. This infection affects especially the parts of the brain concerned with memory and he was left with a memory span of only a few moments. This case study is known as one of the most devastating cases of amnesia as new events and experiences were effaced almost instantly. He suffers from both anterograde and retrograde amnesia. The brain infection he got, herpes encephalitis; is a rare but severe viral infection of the human central nervous system. Clive Wearing can still play the piano and conduct music that he knew before the infection. This suggests that these skills are a part of implicit memory. The fact that he can do this proves the distributed memory system to be true, since the implicit memory is linked to a brain structure other than the hippocampus. Clive’s emotional memory is also intact, which is clearly demonstrated in the affection he constantly shows for his wife. Yet, he must always live in the “present” and is in a way trapped.
Why is this case study so significant?
The case of Clive Wearing provides insight into the biological foundation of different memory systems. Wearing’s episodic memory and some of his semantic memory are lost. He cannot transfer new information into long-term memory either. This has helped psychologists understand more about amnesia and why certain people may remember certain aspects (like music playing). Also it provides more information and proof about LTM and STM.
INFORMATION FOR BOTH HM AND CLIVE WEARING CASE STUDIES
How and Why the Case Study Method was used
The advantage of case studies is that it can provide vital information about brain pathology and can help form theories about normal memory function. Case studies are used to focus down from a very broad field of research into one easily researchable topic. It was used on HM to test whether the scientific theories about the hippocampus actually were correct and it was used on Clive to discover more about amnesia and how it affects someone.
Ethical Considerations;
o Protection of participants; their identities were not revealed if they wanted to remain anonymous
o Very invasive; surveying lasts over many years and many tests were conducted
o Participant consent; except participants may not even remember they gave their consent-family may have given consent but does that make it okay?
DiMaggio (1997)
DiMaggio suggests that schemas are:
· Representations of knowledge (e.g. stereotypes and social roles)
· Mechanisms that simplify cognition in the form of “cognitive shortcuts”. Schematic cognition is shaped and biased by culture. Gender schemas are examples of cognitive schemas shaped by sociocultural ideas about what is appropriate for men and women (i.e. norms).
Baddeley and Hitch (1974)
Baddeley and Hitch (1974) argue that the picture of short-term memory (STM) provided by the Multi-Store Model is far too simple. According to the Multi-Store Model, STM holds limited amounts of information for short periods of time with relatively little processing. It is a unitary system. This means it is a single system (or store) without any subsystems. Working Memory is not a unitary store.
Working memory is STM. Instead of all information going into one single store, there are different systems for different types of information. Working memory consists of a central executive which controls and coordinates the operation of two subsystems: the phonological loop and the visuo-spatial sketch pad.
Central Executive: Drives the whole system (e.g. the boss of working memory) and allocates data to the subsystems (VSS & PL). It also deals with cognitive tasks such as mental arithmetic and problem solving.
Visuo-Spatial Sketchpad (inner eye): Stores and processes information in a visual or spatial form. The VSS is used for navigation.
The phonological loop is the part of working memory that deals with spoken and written material. It can be used to remember a phone number. It consists of two parts
o Phonological Store (inner ear) – Linked to speech perception Holds information in speech-based form (i.e. spoken words) for 1-2 seconds.
o Articulatory control process (inner voice) – Linked to speech production. Used to rehearse and store verbal information from the phonological store.
Aim: To investigate if participants can use different parts of working memory at the same time.
Method: Conducted an experiment in which participants were asked to perform two tasks at the same time (dual task technique) - a digit span task which required them to repeat a list of numbers, and a verbal reasoning task which required them to answer true or false to various questions (e.g. B is followed by A?).
Results: As the number of digits increased in the digit span tasks, participants took longer to answer the reasoning questions, but not much longer - only fractions of a second. And, they didn't make any more errors in the verbal reasoning tasks as the number of digits increased.
Conclusion: The verbal reasoning task made use of the central executive and the digit span task made use of the phonological loop.
Researchers today generally agree that short-term memory is made up of a number of components or subsystems. The working memory model has replaced the idea of a unitary (one part) STM as suggested by the multistore model.
The working memory model explains a lot more than the multistore model. It makes sense of a range of tasks - verbal reasoning, comprehension, reading, problem solving and visual and spatial processing. And the model is supported by considerable experimental evidence.
The working memory applies to real life tasks:
· reading (phonological loop)
· problem solving (central executive)
· navigation (visual and spatial processing)
The weaknesses of this model:
· There is little direct evidence for how the central executive works and what it does. The capacity of the central executive has never been measured.
· Working memory only involves STM so it is not a comprehensive model of memory (as it does not include SM or LTM).
· The working memory model does not explain changes in processing ability that occur as the result of practice or time.
Scoville and Milner (1957)
The case study of H.M. – Scoville and Milner described the case of H.M. who injured his head in a bicycle accident and suffered from seizures until they performed surgery on him that removed his temporal lobe and some of his hippocampus. The seizures stopped but he suffered from amnesia for the rest of his life. The case study provides information on how particular brain areas and networks are involved in memory processing. This helped scientists to formulate new theories about memory functioning.
He could no longer store new memories. He could not transfer new semantic and episodic memories into the LTM. He could, however, form new long-term procedural memories (implicit memories).
Wang and Ross (2007)
Culture is both a system and a process. Culture affects why people remember, how they remember, when they remember, what they remember and whether they find it necessary to remember at all.
When researchers conduct cross-cultural memory research with participants form Western and non-Western cultures they often use tasks developed in psychology laboratories, such as free recall of lists of unrelated words. In such task, the people form Western cultures generally do better. This could be because such asks are meaningless to non-Western people.
Cole and Scribner (1974)
Aim: to investigate free recall in two different cultures, the USA and the Kpelle people in Liberia
Procedure: for the test in Liberia, the researchers used objects that would be familiar to the Liberian children. The list of words was split into four distinct categories. The American children were given free recall tests matching their culture. The researchers presented the words to the participants and asked them to remember as man of them as possible in any order. In the second part of the experiment, the researchers presented the same objects in a meaningful way as part of a story.
Results: The Kpelle children did not improve their performance in free recall memory tests after the age of 10 in the same way as US children; after 15 trials they only remembered 2 more items. Kpelle children who attended school had similar performance to US school children. School children in US and Liberia used categorical recall; they appeared to have chunked the items in to linked categories as they recalled them in groups such as utensils, clothes, vegetables, and tools. When items were presented as part of a story the Kpelle children (non-schooled) had equally good performance as the US children. Children with formal schooling in America and Liberia used this mnemonic, which improved their memory of the items. Children without formal schooling however, did not use the categories to aid their recall and subsequently did not remember as much as children who had attended school.
Evaluation: This concludes that the memory test were westernised, and not universal. However the extent to which it is culture or schooling that influenced memory and categorisation in the study is not entirely clear. The experimental method was used and it can help to establish cause-effect relationship, but as the independent variable was culture it may be hard to fully conclude this experiment.
Riniolo et al. (2003)
Aim: to investigate the reliability of memory for a central detail of eyewitnesses to the Titanic’s final plunge (i.e. whether the Titanic sank intact or broke in two before it went down). It was believed at the time that the ship went down intact.
Procedure: the researchers used archival data and found transcripts from 20 different people that explained what they thought the ship’s state was during the final plunge into the ocean.
Results: 75% stated that the Titanic was breaking apart during sinking and 25% said it was intact. The majority of the 20 selected eyewitness testimonies in this study said the ship broke in two before the plunge. After the hearings it was concluded that the Titanic sank intact and this “myth has been repeated in literature until the discovery of the wreck. Central traits could be recalled, despite the emotional arousal.
Evaluation: participant’s only part of a subgroup might have been interrogation bias, the sample was small, and participants are now dead. Still contributes to knowledge of eyewitness testimony despite traumatic incident.
Brown and Kulik (1977)
Aim: to investigate whether shocking events are recalled more vividly and accurately than other events
Procedure: questionnaires asked 80 participants to recall circumstances where they had learned of shocking events
Results: the participants had vivid memories of where they were, what they did and what they felt when they first heard about a shocking public event such as the assassination of John F. Kennedy. They also said they had flashbulb memories of shocking personal events such as the sudden death of a relative.
Conclusion: these results indicate that flashbulb memory is more likely unexpected and personally relevant events. Brown and Kulik suggest that flashbulb memory is caused by the physiological emotional arousal (activity in the amygdala)
Strengths vs. Weaknesses: it’s not necessarily accurate in regard to details
Neisser and Harsch (1992)
They carried out a real life study on people’s memory of the Challenger disaster. The first data were collected less than 24 hours after the event and the same participants were tested two and a half years later. Most participants did not remember anything correctly but were very confident that they did.
Aim: to test the theory of flashbulb memory by investigating the extent to which memory for a shocking event would be accurate after a period of time.
Procedure: a questionnaire was administered to 106 participants on the day after the space shuttle exploded (Jan 1996). Among the questions asked were 5 about how they heard the news: where they were, what they were doing, who told them, what time it occurred etc. Thirty-two months later the participants were asked to complete the questionnaire again and their results compared to the original. They were asked to rate how confident they were of the accuracy of their memory on a scale from 1 to 5. They were also asked if they had filled out a questionnaire on this topic before.
Results: only 11 participants out of the 44 remembered that they had filled out a questionnaire before. There were major discrepancies between the original questionnaire and the follow-up two and a half years later. The results challenge the predictions of the flash bulb memory theory and also question the reliability of memory in general. Participants were confident they remembered correctly but could not explain the discrepancies between the first and second accounts.
Evaluation: the study was conducted in a natural environment and has higher ecological validity than experiments in a laboratory. The participants may not be representative of the entire population. The degree of emotional arousal when witnessing a shocking public event may be different from experiencing a traumatic event in your own personal life. The importance of an event is highly personal and therefore, still not an overall test of the flash bulb memory but does prove there are some flaws.
Corkin et al. (1997)
He used MRI scans and analysed the extent of the damage to H.M’s brain. The scans showed that temporal lobes including the hippocampus and related structures on both sides were missing. This part of the brain’s memory system plays a crucial role in transforming short-term memories into long-term memories.
These areas are involved in specific neurotransmitter pathways in memory (e.g. acetylcholine is believed to play an important role in learning and episodic memories).
Atkinson and Shiffrin (1968)
Models of Memory: they are primitive diagrams of human memory to help understand the flow of information and how it is stored.
Model 1: The multi-store model of memory (Atkinson and Shiffrin, 1968)
- The multi store model of memory is an explanation of the flow of information through a series of stages.
- Atkinson and Shiffrin (1968) believed that memory involved three different stores. These being sensory memory, short term memory and long term memory.
- They believed that to transfer information into the short-term memory it needs to be attended to (attention is focused on the information in sensory memory) and to transfer information from short-term memory into long-term memory the information needs to be rehearsed.
- Atkinson and Shiffrin found that when information passes through these stores it can be lost by forgetting.
- Their findings were that in sensory memory information is lost through decay, in short-term memory information is lost through displacement and in long-term memory information is lost as an affect of interference.
- Atkinson and Shiffrin also believed that rehearsal is needed for information to be transferred to long-term memory and how well it is rehearsed will determine how effective recall is.
- New approach to memory, (people are information processors)
- Conceptualisation of memory as = support by research
- Possible to make predictions + design experiments based on model
- Has been modified e.g. by Baddeley and Hitch (1974) - working memory model
- Very simplistic, in particular when it suggests that both short-term and long-term memory each operate in a single, uniform fashion.
- Can't account for how interaction between different stores happens
- Research on encoding of LTM has been challenged - now accepted that LTM contains multiple stores (semantic, episodic and procedural)
Glanzer and Cunitz (1966)
Aim: to investigate recency effect in free recall (i.e. in any order)
Procedure: this was a laboratory experiment where participants first heard a list of items and then immediately had to recall them in any order.
Results: participants recalled words from the beginning of the list (primacy effect) and the end of the list (the recency effect) best. The results showed a U-shaped curve. If participants were given a filler task just after hearing the last words, the primary effect disappeared but the recency effect remained.
The recency effect could be due to the words still being active in STM (working memory). Rehearsal could be a factor in the transfer of information into LTM.
Evaluation: the study supports the idea of multiple stores (STM and LTM). This is a controlled laboratory study with highly controlled variables, but there is no random allocation of participants to experimental conditions so it is not a true experiment. There may also be problems with ecological validity.
Bartlett (1932)
Aim: to investigate whether people’s memory for a story is affected by previous knowledge (schemas) and the extent to which memory is reconstructive.
Procedure: Bartlett asked British participants to hear a story and reproduce it after a short time and then repeatedly over a period of months or years (serial reproduction). The story was an unfamiliar Native American legend called “The War of Ghosts”.
Results: The participants remembered the main idea of the story but they changed unfamiliar elements to make sense of the story by using terms more familiar to their own cultural expectations. The story remained a coherent whole although it was changed.
Conclusion: remembering is an active process and are not copies of experience but rather “reconstructions”
Strengths vs. Weaknesses: The weaknesses in this study were ethical considerations that were breeched but this is one of the most famous studies for the learning of memory.
Ethical Considerations: this study was performed in a laboratory and can be criticized for the lack of ecological validity. Participants did not receive standardized instructions and some of the memory distortions may be due to participants’ guessing.
How did the study add to our understanding of schemas and their role in memory?
Bartlett’s theory was unfashionable for many years but has recently been recognised as providing a valuable insight into the reconstructive nature of human memory. His theory was based on Western recall of a native North American folk story. He suggested that we make the following alterations in such cases:
- Rationalisations: people tended to add material to justify parts of the story.
- Omissions: parts of the story, particularly those difficult to understand, were left out.
- Changes of order: the storyline was rearranged in an attempt to make sense out of it.
- Distortions of emotion: people added their own feelings and attitudes to the story.
Darley and Gross (1983)
Aim: to investigate whether a schema or pre-exisiting idea will make people form stereotypes for a particular person
Procedure: participants were told that a girl called Hannah was either rich or poor. The people that were told she was rich split off into a separate group to those that were told she was poor. Both groups watched exactly the same video about her.
Results: participants in the "wealthy family" group rated Hannah's performance above fourth grade, whereas the "poor family" group rated her performance below fourth grade, in spite of watching the same ambiguous video.
Conclusion: these findings demonstrate that stereotypes about socioeconomic status affect perceptions of intelligence.
Strengths vs. Weaknesses: are the results really reliable.
Loftus and Palmer (1974)
Aim: to investigate how information is supplied after a particular event and how it influences a participant’s memory. They wanted to see if changing a verb in a series of critical questions would influence their opinion about a car crash.
Hypothesis: they predicted that by changing the verb in a critical question, they would be able to manipulate the participants’ memory of a car accident.
Research Method: laboratory experiment
Independent variable (IV): The verb that was changed in the critical question for both experiments
Dependent variable (DV): 1st experiment; the participants estimate of speed that the car was going at
2nd experiment; whether the participant believed they saw glass in the car accident
Sampling method and characteristics of participants: The first experiment used 45 students who were all from the University of Washington (volunteer sampling and chosen so that there would be similar results. The second experiment used 150 participants (random sampling but all from US still)
Procedure: The first experiment consisted of seven film clips of traffic accidents that were shown to the participants. Following each clip, the students were asked to write an account of the film they just watched and answer questions, including the critical question; the speed of the vehicles involved in the accident. There were five different questions given to different people, they were all the same but the verb changed.
For example:
Condition 1: 'About how fast were the cars going when they smashed into each other?'
Condition 2: 'About how fast were the cars going when they collided into each other?'
Condition 3: 'About how fast were the cars going when they bumped into each other?'
Condition 4: 'About how fast were the cars going when they hit each other?
Condition 5: 'About how fast were the cars going when they contacted each other?'
The idea was that participants would change their view depending on the condition they got
The second experiment provided a slightly different insight into the origin of the different speed estimates. In particular they wanted to discover whether the verbal label had really distorted the participants’ memories. There watched a final clip of a multiple car accident and there were three conditions and again a verb was manipulated in the critical question.
50 of the participants were asked 'How fast were the cars going when they hit each other?’
50 of the participants were asked 'How fast were the cars going when they smashed into each other?'
50 of the participants were not interrogated about the speed of the vehicles.
One week later the participants were asked to return and without showing any clips, they were asked to answer a series of questions. The critical question was 'Did you see any broken glass?' The critical question was part of a longer series of questions and was placed in a random position on each participants question paper but there was no broken glass in the film.
Results and conclusions:
The interpretation of the results was that the use of different verbs activates different schemas in memory, so that the participant hearing the word “smashed” may actually imagine the accident as more severe than a participant hearing the word “contacted”. Also the researches explained that “smashed” provides the participants with verbal information that activates schemas for a severe accident. Broken glass is in line with this, so the participant is more likely to think that there was broken glass involved.
How did this study contribute to understanding human behaviour?
Loftus’s research indicated that it is possible to create a false memory using post-event information. This helps to understand human behaviour in every-day situations and help understand that eyewitnesses may not remember something in exactly the same way if there is a manipulated situation.
Strengths and Limitations of the methodology:
Strengths are that this experiment allowed for a control of variables. The purpose of being able to control an experiment is so that one can isolate the one key variable, which has been in, selected in order to observe its effect on another variable. This is therefore easier to conclude from. For example the researchers were able to control the age of the participants, the use of video and the location of the experiment.
The limitations of this method were that the experiment was not typical of a real life situation and were held in a laboratory, so wouldn't be how people would normally witness events. They had no personal involvement in the judgement and weren't actually in the event of the car accident. Normally when people witness events in everyday life, people often have some involvement in the action, therefore it is hard to generalise findings from laboratory experiments because they are not ecologically valid.
Another problem with the study was the use of students as the participants as they are not representative of the whole population. They also may be less experienced drivers and therefore less confident in estimating speeds. This may have influenced their answer in the critical questions.
Gender and Cultural Considerations:
All the participants were US students, which mean that the sample was culturally biased.
Ethical Considerations:
Ecological validity as the study was held in a laboratory.
HM
Background information
Henry Molaison (HM) is a famous memory disorder patient whose hippocampus, parahippocampal gyrus, and amygdala were surgically removed whilst trying to cure his epilepsy. For this reason, he suffered awful memory conflicts and was therefore studied for the majority of his life. Following the surgery HM was unable to form any new long-term memories (anterograde amnesia) and couldn’t retrieve some of his existing long-term memory (retrograde amnesia). However, his short-term memories remained regular, limited only by HM’s inability to rehearse. When HM underwent the surgery, William Scoville removed both of his temporal lobes including a structure known as the hippocampus and an area known to be crucial to memory. HM survived the operation and his epilepsy became less damaging; however he now had to go through life suffering from retrograde and anterograde amnesia.
Why is this case study so significant?
This case study has provided a large amount of insight into how important the hippocampus and other regions of the brain are so vital for your memory. H.M. was able to retain some memories for events that happened long before his surgery. This indicates that the medial temporal region with the hippocampus is not the site of permanent storage in itself. It rather seems to play a role in how memories are organised and then stored somewhere else in the brain.
It has presented opportunities that researchers never could have discovered if it wasn’t for the mishap in surgery. As psychologists cannot damage a person’s hippocampus on purpose, just to study memory effects, psychologists owe a lot of gratitude to HM as it has helped them to study the outcomes of someone with intense amnesia.
Clive Wearing (born 1938)
Background information
Clive Wearing was a musician that was in his mid-forties, when suddenly he was struck by a brain infection known as herpes encephalitis. This infection affects especially the parts of the brain concerned with memory and he was left with a memory span of only a few moments. This case study is known as one of the most devastating cases of amnesia as new events and experiences were effaced almost instantly. He suffers from both anterograde and retrograde amnesia. The brain infection he got, herpes encephalitis; is a rare but severe viral infection of the human central nervous system. Clive Wearing can still play the piano and conduct music that he knew before the infection. This suggests that these skills are a part of implicit memory. The fact that he can do this proves the distributed memory system to be true, since the implicit memory is linked to a brain structure other than the hippocampus. Clive’s emotional memory is also intact, which is clearly demonstrated in the affection he constantly shows for his wife. Yet, he must always live in the “present” and is in a way trapped.
Why is this case study so significant?
The case of Clive Wearing provides insight into the biological foundation of different memory systems. Wearing’s episodic memory and some of his semantic memory are lost. He cannot transfer new information into long-term memory either. This has helped psychologists understand more about amnesia and why certain people may remember certain aspects (like music playing). Also it provides more information and proof about LTM and STM.
INFORMATION FOR BOTH HM AND CLIVE WEARING CASE STUDIES
How and Why the Case Study Method was used
The advantage of case studies is that it can provide vital information about brain pathology and can help form theories about normal memory function. Case studies are used to focus down from a very broad field of research into one easily researchable topic. It was used on HM to test whether the scientific theories about the hippocampus actually were correct and it was used on Clive to discover more about amnesia and how it affects someone.
Ethical Considerations;
o Protection of participants; their identities were not revealed if they wanted to remain anonymous
o Very invasive; surveying lasts over many years and many tests were conducted
o Participant consent; except participants may not even remember they gave their consent-family may have given consent but does that make it okay?
DiMaggio (1997)
DiMaggio suggests that schemas are:
· Representations of knowledge (e.g. stereotypes and social roles)
· Mechanisms that simplify cognition in the form of “cognitive shortcuts”. Schematic cognition is shaped and biased by culture. Gender schemas are examples of cognitive schemas shaped by sociocultural ideas about what is appropriate for men and women (i.e. norms).
Baddeley and Hitch (1974)
Baddeley and Hitch (1974) argue that the picture of short-term memory (STM) provided by the Multi-Store Model is far too simple. According to the Multi-Store Model, STM holds limited amounts of information for short periods of time with relatively little processing. It is a unitary system. This means it is a single system (or store) without any subsystems. Working Memory is not a unitary store.
Working memory is STM. Instead of all information going into one single store, there are different systems for different types of information. Working memory consists of a central executive which controls and coordinates the operation of two subsystems: the phonological loop and the visuo-spatial sketch pad.
Central Executive: Drives the whole system (e.g. the boss of working memory) and allocates data to the subsystems (VSS & PL). It also deals with cognitive tasks such as mental arithmetic and problem solving.
Visuo-Spatial Sketchpad (inner eye): Stores and processes information in a visual or spatial form. The VSS is used for navigation.
The phonological loop is the part of working memory that deals with spoken and written material. It can be used to remember a phone number. It consists of two parts
o Phonological Store (inner ear) – Linked to speech perception Holds information in speech-based form (i.e. spoken words) for 1-2 seconds.
o Articulatory control process (inner voice) – Linked to speech production. Used to rehearse and store verbal information from the phonological store.
Aim: To investigate if participants can use different parts of working memory at the same time.
Method: Conducted an experiment in which participants were asked to perform two tasks at the same time (dual task technique) - a digit span task which required them to repeat a list of numbers, and a verbal reasoning task which required them to answer true or false to various questions (e.g. B is followed by A?).
Results: As the number of digits increased in the digit span tasks, participants took longer to answer the reasoning questions, but not much longer - only fractions of a second. And, they didn't make any more errors in the verbal reasoning tasks as the number of digits increased.
Conclusion: The verbal reasoning task made use of the central executive and the digit span task made use of the phonological loop.
Researchers today generally agree that short-term memory is made up of a number of components or subsystems. The working memory model has replaced the idea of a unitary (one part) STM as suggested by the multistore model.
The working memory model explains a lot more than the multistore model. It makes sense of a range of tasks - verbal reasoning, comprehension, reading, problem solving and visual and spatial processing. And the model is supported by considerable experimental evidence.
The working memory applies to real life tasks:
· reading (phonological loop)
· problem solving (central executive)
· navigation (visual and spatial processing)
The weaknesses of this model:
· There is little direct evidence for how the central executive works and what it does. The capacity of the central executive has never been measured.
· Working memory only involves STM so it is not a comprehensive model of memory (as it does not include SM or LTM).
· The working memory model does not explain changes in processing ability that occur as the result of practice or time.
Scoville and Milner (1957)
The case study of H.M. – Scoville and Milner described the case of H.M. who injured his head in a bicycle accident and suffered from seizures until they performed surgery on him that removed his temporal lobe and some of his hippocampus. The seizures stopped but he suffered from amnesia for the rest of his life. The case study provides information on how particular brain areas and networks are involved in memory processing. This helped scientists to formulate new theories about memory functioning.
He could no longer store new memories. He could not transfer new semantic and episodic memories into the LTM. He could, however, form new long-term procedural memories (implicit memories).
Wang and Ross (2007)
Culture is both a system and a process. Culture affects why people remember, how they remember, when they remember, what they remember and whether they find it necessary to remember at all.
When researchers conduct cross-cultural memory research with participants form Western and non-Western cultures they often use tasks developed in psychology laboratories, such as free recall of lists of unrelated words. In such task, the people form Western cultures generally do better. This could be because such asks are meaningless to non-Western people.
Cole and Scribner (1974)
Aim: to investigate free recall in two different cultures, the USA and the Kpelle people in Liberia
Procedure: for the test in Liberia, the researchers used objects that would be familiar to the Liberian children. The list of words was split into four distinct categories. The American children were given free recall tests matching their culture. The researchers presented the words to the participants and asked them to remember as man of them as possible in any order. In the second part of the experiment, the researchers presented the same objects in a meaningful way as part of a story.
Results: The Kpelle children did not improve their performance in free recall memory tests after the age of 10 in the same way as US children; after 15 trials they only remembered 2 more items. Kpelle children who attended school had similar performance to US school children. School children in US and Liberia used categorical recall; they appeared to have chunked the items in to linked categories as they recalled them in groups such as utensils, clothes, vegetables, and tools. When items were presented as part of a story the Kpelle children (non-schooled) had equally good performance as the US children. Children with formal schooling in America and Liberia used this mnemonic, which improved their memory of the items. Children without formal schooling however, did not use the categories to aid their recall and subsequently did not remember as much as children who had attended school.
Evaluation: This concludes that the memory test were westernised, and not universal. However the extent to which it is culture or schooling that influenced memory and categorisation in the study is not entirely clear. The experimental method was used and it can help to establish cause-effect relationship, but as the independent variable was culture it may be hard to fully conclude this experiment.
Riniolo et al. (2003)
Aim: to investigate the reliability of memory for a central detail of eyewitnesses to the Titanic’s final plunge (i.e. whether the Titanic sank intact or broke in two before it went down). It was believed at the time that the ship went down intact.
Procedure: the researchers used archival data and found transcripts from 20 different people that explained what they thought the ship’s state was during the final plunge into the ocean.
Results: 75% stated that the Titanic was breaking apart during sinking and 25% said it was intact. The majority of the 20 selected eyewitness testimonies in this study said the ship broke in two before the plunge. After the hearings it was concluded that the Titanic sank intact and this “myth has been repeated in literature until the discovery of the wreck. Central traits could be recalled, despite the emotional arousal.
Evaluation: participant’s only part of a subgroup might have been interrogation bias, the sample was small, and participants are now dead. Still contributes to knowledge of eyewitness testimony despite traumatic incident.
Brown and Kulik (1977)
Aim: to investigate whether shocking events are recalled more vividly and accurately than other events
Procedure: questionnaires asked 80 participants to recall circumstances where they had learned of shocking events
Results: the participants had vivid memories of where they were, what they did and what they felt when they first heard about a shocking public event such as the assassination of John F. Kennedy. They also said they had flashbulb memories of shocking personal events such as the sudden death of a relative.
Conclusion: these results indicate that flashbulb memory is more likely unexpected and personally relevant events. Brown and Kulik suggest that flashbulb memory is caused by the physiological emotional arousal (activity in the amygdala)
Strengths vs. Weaknesses: it’s not necessarily accurate in regard to details
Neisser and Harsch (1992)
They carried out a real life study on people’s memory of the Challenger disaster. The first data were collected less than 24 hours after the event and the same participants were tested two and a half years later. Most participants did not remember anything correctly but were very confident that they did.
Aim: to test the theory of flashbulb memory by investigating the extent to which memory for a shocking event would be accurate after a period of time.
Procedure: a questionnaire was administered to 106 participants on the day after the space shuttle exploded (Jan 1996). Among the questions asked were 5 about how they heard the news: where they were, what they were doing, who told them, what time it occurred etc. Thirty-two months later the participants were asked to complete the questionnaire again and their results compared to the original. They were asked to rate how confident they were of the accuracy of their memory on a scale from 1 to 5. They were also asked if they had filled out a questionnaire on this topic before.
Results: only 11 participants out of the 44 remembered that they had filled out a questionnaire before. There were major discrepancies between the original questionnaire and the follow-up two and a half years later. The results challenge the predictions of the flash bulb memory theory and also question the reliability of memory in general. Participants were confident they remembered correctly but could not explain the discrepancies between the first and second accounts.
Evaluation: the study was conducted in a natural environment and has higher ecological validity than experiments in a laboratory. The participants may not be representative of the entire population. The degree of emotional arousal when witnessing a shocking public event may be different from experiencing a traumatic event in your own personal life. The importance of an event is highly personal and therefore, still not an overall test of the flash bulb memory but does prove there are some flaws.