Memory Flashcards
What is short term memory?
Short term memory stores and allows recall of information for a period of several seconds.
What is long term memory?
Stores and enables us to recall information from the more distant past.
In which 3 ways are STM and LTM different?
Duration, capacity and encoding
What is duration?
A measure of how long information can be stored for or how long it lasts.
Who investigated the duration of STM?
Peterson and Peterson.
- 24 undergraduate students were presented with a consonant trigram.
- They were then asked to count backwards in threes to stop them repeating/rehearsing the consonant trigram.
- After intervals of either 3, 6 ,9, 12, 15 or 18 seconds, participants had to stop counting and repeat the trigram.
What were the results of Peterson and Peterson’s study?
- Participants could remember about 80% of trigrams after 3 seconds.
- 20% after 9 seconds
- Less than 10% when there was a 18 second interval.
- The maximum STM duration is about 18-30 seconds.
Evaluate Peterson and Peterson’s study on the duration of STM.
Strengths
1) It is a lab experiment where variables can be tightly controlled e.g how many trigrams are presented. The procedure can also be replicated to test if results are reliable.
Weaknesses
1) Trigrams are unrealistic things to remember. Therefore it has low ecological validity.
2) Trigrams presented on earlier trials may have cause confusion when participants came to remember trigrams in later trials.
Who investigated the duration of LTM?
Bahrick et al.
- Tested how well about 400 American participants could remember their former classmates by asking them to identify pictures, matching names to pictures.
What were the results of Bahrick’s study?
- Even after 48 years, when asked to link names and faces, accuracy was at about 70%.
- However, when participants were asked to free recall to names of their classmates, accuracy was about 30%
- This backs up the idea that long term memories can last a lifetime.
Evaluate Bahrick et al’s study.
Strengths
- This was a natural experiment with meaningful material so has higher ecological validity because remembering names is an everyday task.
Weaknesses
- It only looked at a specific type of information (names of classmates). This type of information is particularly meaningful and regularly rehearsed. Not all LTM’s remain there for a lifetime.
- Because it is a natural experiment, the experimenter had less control of the IV thus it’s likely some of the names had been rehearsed e.g if classmates were still in touch. This would be a confounding variable, making results potentially invalid.
What is capacity?
A measure of how much information can be held or stored.
How did Jacobs investigate the capacity of the STM?
- Jacobs developed a serial span technique.
- The researcher read out 4 digits and the participant was asked to repeat it back.
- Another digit was added until the participant could not repeat back the digit string accurately.
What were the results of Jacobs study?
- On average about 9 digits and 7 letters were correctly recalled.
- This capacity increased with age.
- This may be because there is a gradual increase in brain capacity, and/or because people develop strategies to improve their digit span, such as chunking.
- Digits may have been easier to recall as there are only 10 digits to remember, compared to 26 letters.
Evaluate Jacob’s study.
- Jacob’s research lacks ecological validity- learning random lists of numbers is not a realistic test of STM.
- Given Jacob’s study was conducted so long ago we also cannot be sure that extraneous variables were controlled.
What did Miller conclude?
- He concluded that the STM has a capacity of 7+-2 items.
- He also said that memory capacity can be increased through a process called chunking.
Which 3 possible ways can information be coded?
- Acoustic coding: storing information in terms of the way it sounds.
- Semantic coding: coding information in terms of its meaning.
- Visual coding: storing information in terms of the way it looks.
How did Baddely investigate coding?
- Participants were shown a sequence of 5 words under one of the four conditions, and then immediately had to write them down in order.
- Acoustically similar, acoustically dissimilar, semantically similar, semantically dissimilar
What were the results of Baddely’s experiment?
- When tested immediately, participants were least accurate with the acoustically similar words- they commonly got them muddled.
- When tested 20 minutes later, participants were least accurate with semantically-similar words.
- In conclusion, information is normally coded acoustically in the STM and semantically in the LTM.
Evaluate Baddely’s experiment.
- Low ecologically validity- the words were a meaningless list, and perhaps semantic coding is only used when information is more meaningful.
- This means that the results have limited application to real life.
Who first introduced the multi-store model?
Atkinson and Shiffrin in 1968
What are the 3 unitary stores of the multi-store model?
1) Sensory register or sensory memory
2) Short term memory
3) Long term memory
What does the multi-store model work?
1) Information is detected by the sense organs and enters the sensory memory.
2) If attended to this, information enters the STM.
3) Information from the STM is transferred to the LTM only if that information is rehearsed.
4) If rehearsal does not occur, then information is forgotten, lost from STM through the processes of displacement or decay.
What are the 5 separate sensory stores?
1) Iconic store- Where visual images are kept for a short period.
2) Echoic store- Where auditory senses are kept for a short period.
3) Haptic store- Retains physical senses of touch and internal muscle tensions.
4) Gustatory store: Related to taste information
5) Olfactory store: Related to smell
What is the duration of the sensory register?
Less than half a second (250 milliseconds)
Describe how Sperling investigated the sensory register.
- In a lab experiment, pps were shown a grid with three rows of four letters for 50 milliseconds.
- They had to then immediately recall either the whole grid, or a randomly chosen row.
What were the results of Sperling’s experiment?
- When pps were asked to recall a particular row, pps could recall on average, 3 out of 4 items, no matter which row had been selected.
- In conclusion, as the pps didn’t know which row was going to be selected by still managed to recall 3/4 letters in a row, suggests that the whole grid was held in their sensory register.
Evaluate Sperling’s experiment.
- Because it was a lab experiment, it was highly scientific.
- The variables could be controlled, and it would be easy for someone to replicate the study.
- However the artificial setting of the study means it lacks ecological validity-people don’t normally have to recall letters in response to sound, so the results might not represent what would happen in the real world.
What is the primacy effect?
- The primacy effect is when we are more likely to remember words at the beginning of a list because they are the first words that we see, and we have enough time to rehearse them.
- This increases the likelihood that they will move into the LTM.
What is the recency effect?
- The recency effect is when we are most likely to remember words from the end of the list as they were still held in our STM.
Explain Murdock’s study and how it proves the recency and primacy effect.
- Murdock asked participants to learn a list of words that varied in length from 10 to 40 words and free recall them.
- Each word was presented for one or two seconds.
- He found that the probability of recalling any word depended on its position on its list.
- Words presented either early in the list or at the end were more often recalled, but the ones in the middle were more often forgotten. This is known as serial position effect.
- Murdock suggested that words early in the list were put into LTM (primacy effect) because the person has time to rehearse each word acoustically.
- Words from the end of the list went into the short term memory which can typically hold about 7 items.
Which case study supports the idea that STM and LTM are separate stores?
- H.M had an operation to remove the hippocampus from both sides of his brain to reduce the severe epilepsy he suffered.
- After the operation, HM’s personality remained intact and he could still recall a list of 6 words in order.
- This shows HM’s short term memory was still intact, but his surgery had left him unable to form new long term memories.
What are the strengths of the MSM?
1) Can explain primacy and recency effects.
2) Case studies support the idea that STM and LTM are separate stores.
3) Brain-scanning techniques have also supported the idea that long and short term memories are separate stores: Prefontal cortex was active during STM but not LTM tasks.
What are the weaknesses of the MSM?
1) The idea that all information needs to be rehearsed in order to move in the LTM is an oversimplification as MSM does not explain flashbulb memories.
- It doesn’t take into account that information more relevant to our lives is far easier to remember.
- Similarly if we do not fully understand a piece of information no matter how many times we rehearse it, it is unlikely it will stay in our LTM for a long period of time.
- Furthermore, we don’t need to rehearse information at all to form LTMs e.g Kulik and Brown found highly emotional, significant or shocking events are easily stored in our long term memories without any rehearsal.
2) Evidence suggests that the STM and LTM are not single stores.
- It is now believed that the STM can be divided up into 2 stores: one for visual information and another for auditory information.
- In support, patient K.F sustained brain damage from a motorbike accident which left him with a severely impaired STM for verbal information only (his visual STM showed no impairment)
- This suggests that K.F had damaged just part of his STM and therefore it is not a unitary store as the MSM argued.
3) Most studies supporting the MSM lack ecological validity.
- In most supporting studies participants asked to complete simple, unrealistic tasks, which didn’t test their memories in ways relatable to everyday life e.g random lists of words,digits, trigrams.
- In real life we tend to form memories related to meaningful information.
- This suggests that the MSM lacks external validity because supporting evidence may not reflect how the memory works in real life.
What are the three types of long term memory?
1) Episodic memory
2) Semantic memory
3) Procedural memory
What is episodic LTM?
- It is the memory that gives individuals an autobiographical record of personal experiences.
- The strength of episodic memories is influenced by: emotions present at the time memory is coded e.g traumatic events are often well recalled due to their high emotional content.
What is semantic LTM?
- This type of memory contains all knowledge (facts,concepts and meanings) the individual has learned.
- The strength of semantic memories is dependent upon the degree of processing occurring during coding.
What is procedural LTM?
- It is a type of implicit memory permitting individuals to perform learned tasks with little conscious thought e.g riding a bike.
What are the strengths of the types of LTM?
1) Supported by case studies
- E.g H.M & Clive Wearing both had severely impaired episodic memories but could also learn new skills (meaning their procedural LTM was still intact)
- After suffering a viral infection which caused severe brain damage, Clive Wearing could still read music and play the piano.
2) Evidence from brain scans shows different types of LTM are stored in different parts of the brain. E.g semantic memory seemed to be located in left prefontal cortex and episodic memory in the right prefontal cortex. This finding has been well replicated thus making the results reliable.
What are the weaknesses for the types of LTM?
1) There is evidence of gender differences in LTMs.
- Herlitx assessed LTM abilities in 1000 Swedish pps and found that females consistently performed better on tasks requiring episodic LTM, although there were no gender differences in semantic LTM ability.
- This further supports the idea that semantic and episodic memories are different.
Who introduced the Working Memory Model?
Baddeley and Hitch in 1974
Why was the WMM introduced?
- Baddeley and Hitch argued that the short term memory was too simple.
- They argued that the STM is not a unitary store and it has sub stores each responsible for processing different types of information.
What are the 4 components of WMM?
1) Central executive
2) Phonological loop
3) Visuo-spatial sketchpad
4) Episodic buffer
What is the role of the central executive?
- The central executive has overall control.
- It processes information in all sensory forms.
- Directs attention to important tasks
- Monitors incoming information
- Involved in problem solving/decision making
- It has a limited capacity.
What is the role of the phonological loop?
- Temporarily stores and rehearses word-based information so is active whenever you read, listen or speak.
- Stores this word based information in the order in which it arrives.
- Can be subdivided into the phonological store and articulatory process.
- The phonological store acts as an inner ear and holds information in speech based form for 1-2 seconds.
- The articulatory process allows maintenance rehearsal of the word-based information.
What is the role of the visual-spatial sketch pad?
- It is acts as a mental workplace for storing and manipulating a limited amount of visual and spatial information for a brief period of time.
- The visuo spatial sketch pad plays an important role in helping us keep track of where we are in relation to other objects as we move through our environment.
- It’s divided into visual cache (stores visual data) and inner scribe (remembers arrangement of objects in space).
What is the role of the episodic buffer?
- Acts as a backup store which communicates with both long term memory and integrates the visual, spatial and verbal information processes by other stores.
- It also records the order in which events happen.
How does Baddely and Hitch’s study (1976) prove the WMM?
- Conducted an experiment in which participants were asked to perform two tasks at the same time- 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.
- Results showed that as the number of digits increased in the digit span tasks, participants took longer to answer the reasoning questions, but not much longer.
- They also didn’t make any more errors in the verbal reasoning tasks as the number of digits increased.
- In conclusion, the verbal reasoning task made use of the central executive and the digit span task made use of the phonological loop.
What are the strengths of the WMM?
1) It can account for dual-tasking- the fact that we can carry out two tasks at once if one is word-based and one is visual. This is because we can use the phonological loop to do the verbal task and at the same time, the visuo-spatial sketchpad to do the visual task.
2) The WMM can explain how we carry our everyday tasks e.g verbal reasoning,(phonological loop) problem solving (central executive) and navigation (visuo-spatial) far better than the MSM can. We can therefore say it has greater face validity.
3) The working memory model accounts for case studies like K.F which show that STM has different stores.
- K.F had working LTM but some aspects of his STM were impaired.
- His STM for word-based information was significantly worse than for visual information.
- This supports the idea that there are separate visual and verbal STM stores.
What are the weaknesses of the WMM?
1) The exact role of the central executive remains unclear.
- It has been argued that it directs attention and decides which slave system to use. However this is very vague.
- It has been suggested that it may consist of subcomponents.
- The capacity of the central executive has also never been measured, suggesting that the WMM lacks necessary detail.
2) Some of the evidence from brain-damaged patients is not necessarily reliable because it concerns single case studies who have had traumatic experiences.
- This makes it hard to make a generalisation about ‘normal’ memory processing because these case studies are unique.
3) The WMM is restricted to STM and says nothing about the LTM nor the sensory memory.
What was Baddely et al’s experiment (1973)?
- Participants were given a simple tracking task- to follow a light stop with the pointer or simultaneously also carrying out either:
1) A visual imagery task where they had to imagine looking at an angular block capital letter such as H, T, F and E and answer questions about their corner.
2) A verbal reasoning task. - The results showed that participants found it much harder to track the light and carry out task 1, than they did task 2.
- In conclusion when participants completed the tracking task alongside task 1, both tasks were competing for the visuo-spatial sketch pad resources.
What are the main two explanations of forgetting?
1) Interference including proactive and retroactive interference.
2) Retrieval failure due to absence of cues.
What is the interference theory?
- Forgetting occurs in the LTM because two memories are in conflict.
- This might result in forgetting or distorting one or the other or both.
- This is more likely to happen if memories are similar.
What is proactive interference?
- When an old memory interferes with the forming of a new memory e.g a teacher struggling to learn the names of students in her new class because she’s confusing the names with students in her old class.
What is retroactive interference?
- When new memories interfere with old memories e.g forgetting the names of students in the old class after learning the names of students in current class.
What are the strengths of interferences as an explanation of forgetting?
1) It is supported by many controlled lab studies which have shown that both types of interference lead to information in LTM being forgotten.
- E.g McGeoch and McDonald’s study supported the interference study.
- Participants had to learn a list of words until 100% accurate.
- Then participants were divided into six groups and had to learn a new list.
- The words and the new list varied in terms of how similar they were to the original list.
- Group 1: Synonyms
- Group 2: Antonyms
- Group 3: Unrelated words
- Group 4: Nonsense syllables
- Group 5: 3 digit numbers
- Group 6: No new list
- The results showed that those who had to learn numbers did best in recalling the original list of words, presumably because numbers do not interfere with words.
- However the group who were given the list of synonyms for the interference task had the lowest recall score because the original list of words had a similar meaning to the other lists of words.
- And as it has been shown that interference is most likely to occur when two pieces of information are similar, this study supports the notion
- Also as lab studies are well controlled, extraneous variables are minimised.
- For example, in McGeoch and McDonald’s study all lists given to the pps would have been standardised and matched on levels of difficulty reducing the extraneous variables of lists being too hard or too easy.
- This supports the idea that interference is that a valid explanation of forgetting.
2) Another strength of interference theory is some realistic studies have been conducted. E.g Baddely and Hitch (1977)
- Asked to rugby players to remember names of teams they had played earlier in the season.
- The results showed that accurate recall of teams they had played did not depend on how long ago did last played a match.
- They were equally accurate recalling the last time they played whether or not it was three days ago or three weeks ago.
- More important was the a number of games they had played in meantime.
- This is presumably because the more games they played,the greater the risk of new teams they had played interfering with their memories of previous teams they had played
Describe McGeoch and McDonald’s experiment (1931) on interference.
- Participants had to learn a list of words until 100% accurate.
- Then participants were divided into six groups and had to learn a new list.
- The words and the new list varied in terms of how similar they were to the original list.
- Group 1: Synonyms
- Group 2: Antonyms
- Group 3: Unrelated words
- Group 4: Nonsense syllables
- Group 5: 3 digit numbers
- Group 6: No new list
- The results showed that those who had to learn numbers did best in recalling the original list of words, presumably because numbers do not interfere with words.
- However the group who were given the list of synonyms for the interference task had the lowest recall score because the original list of words had a similar meaning to the other lists of words.
- And as it has been shown that interference is most likely to occur when two pieces of information are similar, this study supports the notion.
Describe Baddely and Hitch’s experiment (1977).
- Asked to rugby players to remember names of teams they had played earlier in the season.
- Injuries and suspensions meant that there was a variation how many games participants had played across the season, and how long they last played a match.
- The results showed that accurate recall of teams they had played did not depend on how long ago did last played a match.
- They were equally accurate recalling the last time they played whether or not it was three days ago or three weeks ago.
- More important was the a number of games they had played in meantime.
- This is presumably because the more games they played,the greater the risk of new teams they had played interfering with their memories of previous teams they had played.
What are the weaknesses of interference as an explanation of forgetting?
1) Most supporting evidence such as lab studies use unrealistic material.
- People rarely remember lists of random words in real life.
- Interference may therefore be more likely in a lab study compared to real life.
2) The time period between learning list of words and recalling them tends to be short. E.g 20 minutes.
- In real life there tends to be much longer gaps between when we learn new information.
- Therefore supporting research may lack validity and not reflect how we learn in real life.
- The role of interference as shown by the lab studies may be exaggerated.
3) Research has also shown that the effects of interference can be overcome using cues.
- In support, Tulving gave participants 5 lists of 24 words organised into categories. It was found that recall was about 70% for the first list and this accuracy decreased as the lists went on.
- This was presumably due to interference.
- However when participants were reminded of each category, recall accuracy improved to about 30% again.
- This suggests that memories of the words were stored in LTM but that cues were needed to access some of the words.
What does the “retrieval failure due to absence of cues” argue?
- This theory argues that the information is often stored in the LTM but cannot be retrieved due to lack of cues.
- When information is initially placed in memory, associated cues are stored at the same time.
- These cues are often needed to trigger the memory.
- Forgetting in LTM is usually down to retrieval failure.
What is the encoding specificity principle?
- The encoding specificity principle suggests that cues will help retrieval if the same cues are present encoding and retrieval.
- The closer the retrieval cue to the original cue, the more effective the cue in triggering the memory.
What are the two types of cues?
1) Cues which are linked meaningfully to the information to be remembered. For example the cue ‘STM’ may help you remember lots of information relevant to STM.
2) Cues which are not linked to meaningfully to the information to be remembered but nevertheless may relate to the context in which the learning occurs. E.g weather (external cues- also known as context-dependent) in which we learn the information and the mental state we are in (internal cues- also known as state-dependent). These cues are not meaningful linked to the memory but still act as cues to recall.
How does Tulving and Pearlstone’s experiment support the role of the encoding specificity principle in improving recall?
- They got participants to recall 48 words that belonged to one of the 12 categories.
- As each word was presented it was preceded by its category.
- If the cue was not present at recall then overall recall for the 48 words was 60%.
- If the cue was not present then recall fell to 40%.
- In conclusion retrieval of information stored in LTM is far better when there are cues to trigger the memory- supporting the idea of the encoding specificity principle.
When can context-dependent forgetting occur?
- It can occur when the environment during recall is different from the environment you were in when you were learning.
How did Godden and Baddeley (1975) investigate context dependent forgetting?
- 18 divers from a diving club were asked to learn lists of 36 unrelated words of two or three syllables and then recall them.
- The 4 conditions were: learn on beach recall on beach, learn on beach recall underwater, learn underwater, recall on the beach, learn underwater recall underwater.
- Recall was better when the environment in which they learnt and recalled information matched and poorer when they did not match.
- For example the mean recall score is higher when the divers land and recalled on the beach this shows context dependent forgetting because information is forgotten when contacts at record did
Evaluate Godden and Baddely’s experiment.
- Context dependent forgetting may also depend on what type of memory been tested.
- When the experiment was repeated but instead of free recall of words participants were asked if they recognised words read to them this time there was no difference in performance across groups.
- This suggests context cues only affect memory when tested in a certain way.
When can state dependent forgetting occur?
- State-dependent forgetting occurs when your mood or psychological state during recall is different from the mood you were in when you were learning.
How did Carter and Cassaday (1998) prove state-dependent forgetting?
- They give participants antihistamines drugs for controlling their hay fever (making them drowsy).
- Participants had to learn lists of words and passages of information and then recall.
- There were 4 groups: in 2 group’s internal state when remembering and recalling matched (both situations taken drug or not taken drug) in other 2, internal state mismatched (only taken drug in one situation).
- Results showed that participants recalled best when the internal state matched learning and recall.
- However, when there was a mismatch on the internal state- performance on memory test was worse.
- In conclusion when internal cues are absent forgetting is more likely.
What are the strengths of the retrieval failure explanation of forgetting?
1) Range of research (both controlled lab studies and real life situations) shows retrieval failure is a major explanation of forgetting.
- For example, Godden and Baddely’s study shows that the context is an important cue when remembering information- the divers who had learned and recalled underwater remember more than the divers who learned on land but recalled underwater.
- Such a wide range of supporting evidence suggests it’s a valid explanation of forgetting.
2) Concept of context-dependent cues has real life applications.
- It suggests that remembering the context in which you encoded the memory may improve memory recall.
- This is a basic principle of the cognitive interview.
What are the weaknesses of the retrieval failure explanation of forgetting?
1) Retrieval cues do not always work since our learning is related to a lot more than just cues - also many of the research studies carried out, tend to focus on word lists or passages- this lacks ecological validity since we are not just learners at school but we are learning throughout our lifetime thus most studies lack realism and do not give an overall picture of retrieval failure as an explanation for forgetting.
2) Furthermore, it is actually very different to test the encoding specificity principle since we don’t know what cues are meaningful to individuals and how they are encoded during learning.
E.g you can’t prove exactly what cues and how they are encoded during learning since you are not able to analyse peoples minds at the time of learning.
what is the eyewitness testimony?
- The ability of people to remember the detail of events, such as accidents and crimes, which they themselves have observed.
- It has been suggested that the accuracy of EWT can be affected by misleading information including leading questions and post event discussions.
What are leading questions?
- A leading question is a question that suggests to the witness what answer is desired, or leads him/her to give a certain answer because of the way it was phrased.
How did Loftus and Palmer investigate the effect of leading questions on eyewitness testimony?
- 45 students were shown a video of a car accident and then asked a question about the speed of the car on impact.
- One group of participants were asked ‘how fast were the cars going when they hit each other’.
- Other participants were asked same question but the verb ‘hit’ was replaced with either smashed bumped collided or contacted.
- The verb used had a significant effect on the estimated speed.
- The verb ‘contacted’ led to the lowest estimated speed (a mean of 31.8mph) and ‘smashed’ the highest. (a mean of 40.5mph)
- Some of the verbs used in the experimenter’s questions were leading, encouraging participants to believe that cars were going faster or slower than they really were.
What was the second experiment that Loftus and Palmer conducted?
- Tried to see if the wording of a leading question changed the pp’s memory of the film clip.
- PPs who originally heard ‘smashed’ were more likely to report seeing broken glass (there was none) than those who heard the verb hit.
What was Loftus and Zanni’s experiment?
- Pps were shown a video of a car accident.
- When they were asked if they had seen ‘a’ broken headlight, 7% of pps said yes
- When they were asked if they had seen ‘the’ broken headlight, 17% of pps said yes even though there was no broken headlight.
- Therefore the word “the” was misleading
What is post-event discussion?
When witnesses to an event discuss what they have experienced after the event
Why is post-event discussion argued to affect accuracy of EWT?
1) Memory contamination: Witnesses mix info from other witnesses into their own memories.
2) Memory conformity: Witnesses pick up details from the eye witness testimony of other witnesses because they want social approval or because they believe other witnesses are right, and they are wrong.
Describe Gabbert et al’s study into post-event discussion.
- Pps were put in pairs and watched video of a crime but filmed from different views- so they saw slightly different elements.
- Before they were asked about the content of the video, the pps were allowed to discuss what they had seen.
- 71% of pps mentioned aspects of the video they had not seen, but their partner had.
- Therefore, we can conclude the witnesses will absorb information from other witnesses, either because of memory contamination or memory conformity.
Give strengths of research into the effects of misleading info on EWT
1) Many of the studies conducted into EWT are highly replicable.
- E.g Loftus used a range of controlled experiments illustrating different examples of EWT.
- Due to the control over extraneous variables, it is easy to replicate.
- This is a strength as it means that researchers using identical procedures should produce similar results.
- The large number of studies conducted into EWT have found the same outcome- that misleading information negatively effects EWT.
- Therefore allows reliability to be tested too.
2) It has practical applications for the real world where the consequences of inaccurate EWT can be very serious.
- E.g Loftus’s research revealed that leading questions can lead to significant distortions in memory.
- This is a strength as understanding this informs interviewers to avoid biased info from witnesses.
- This is particularly important in the legal system when interviewing eyewitnesses and so this should help their accuracy of recall of events.
Give limitations of research into the effects of misleading info on EWT
1) Lacks ecological validity
- A limitation of Loftus’ research is that the tasks used are artificial.
- For example, Loftus used a video of a car accident and this not the same as experiencing a real incident.
- It is difficult to reproduce real life EWT conditions in a laboratory for practical and ethical reasons
- This is a problem as real life events often take place unexpectedly and in an atmosphere of high tension, meaning they may be recalled significantly different to laboratory settings. - Furthermore, Foster et al. found that if participants thought they were watching a real life robbery important to a real trial, their identification of the robber was much more accurate
- Therefore controlled research settings such as Loftus’ may lack ecological which in turn may undermine the findings
2) Contradictory real life research
- A further limitation of Loftus’ research is that there is contradictory evidence from real- life research
- For example, Yuille & Cutshall studied a real-life situation of a shooting outside a gun shop in Canada.
- They examined witnesses’ recall of a real-life crime five months after the incident and asked them two misleading questions.
- They found the misleading questions did not alter accuracy of recall from their original statements.
- This is a problem as in Loftus’ research the important information (the speed of the car) was distorted simply by the verb used. - However, EWT studied in real life situations has contradictory results, where misleading information did not distort accuracy of recall
- Therefore the validity of Loftus’ methodology and findings are reduced
What does the Yerkes-Dodson law state?
Performance will increase with stress, but only to a certain point, where it decreases drastically.
Explain the effect of anxiety on EWT relating to the Yerkes-Dodson Law.
- Lower levels of anxiety produce lower levels of recall accuracy
- Memory becomes more accurate as the level of anxiety experienced increases
- After the optimal point of anxiety, if an eyewitness experiences any more stress than this, then their recall of the event suffers a drastic decline.
- TO CONCLUDE: TOO MUCH OR TOO LITTLE ANXIETY WILL AFFECT RECALL, SO A MEDIUM AMOUNT OF ANXIETY WILL AID THE MOST ACCURATE RECALL
What is the weapon focus effect and why is it an example of high anxiety?
- High anxiety can be created through the weapon focus effect.
- A crime may be committed and when the perpetrator pulls out a weapon, such as a knife or gun, it increases the anxiety levels of observers as their focus shifts from the crime to the weapon.
Describe Johnson and Scott’s experiment on testing effects of anxiety on EWT.
- Pps sat outside a laboratory and heard one of the 2 situations from inside.
1) A friendly conversation followed by a man emerging carrying a pen with grease on his hands.
2) An argument, with smashing glass and overturned furniture, followed by a man emerging with a blood stained paper knife. - All pps had to identify the man on the basis of 50 photos.
- Witnesses were 49% accurate in identifying the man with the pen, compared to 33% accuracy with the knife.
- This shows that anxiety affected recall since when pps were in the high anxiety condition (bloodied knife) this lead them to focus on the weapon rather than the face of the mann.
Give strengths on research conducted about effects of anxiety on EWT
1) Highly replicable
- Due to the control over extraneous variables in much of the research such as Johnson and Scott it is easy to replicate.
- This is a strength as this means that researchers using identical procedures should produce similar results.
- Therefore the ability to replicate Johnson and Scott’s research allows for reliability to be tested and has thus yielded reliable findings
Give limitations on research conducted about effects of anxiety on EWT.
1) Contradictory real life research
- A further limitation of Johnson’s and Scott’s research is that there is contradictory evidence from real-life research
- For example, Christianson and Hubinette conducted a natural experiment, which found that emotional arousal may actually enhance the accuracy of memory.
-They questioned 58 real witnesses to a real bank robbery.
- They found that witnesses who had been threatened in some way were much more accurate in their recall of details, than those who had been onlookers and less emotionally aroused
-This is a problem as this completely opposes Johnson and Scott’s findings and it shows that people (especially victims) are good at remembering highly stressful events in real life rather than artificial surroundings
Therefore the validity of Johnson and Scott’s methodology and findings are reduce
2) Ethical issues
- A further limitation of research into anxiety on EWT is it often
breaks ethical guidelines
- For example, the methods used to induce anxiety, such as a violent films, are likely to cause mild harm
-This is an issue as Psychologists cannot cause unnecessary psychological harm in their research and must gain informed consent from participants to take part.
-They are not only breaking the ethical guideline of harm but also participants would often be deceived about the aim of the experiment when giving consent to take part
-Therefore as the research breaks ethical guidelines the credibility of the theory of anxiety on EWT is reduced
What is the cognitive interview?
The cognitive interview is a police technique which encourages witnesses to recreate the original context using four structural stages.
Who developed the cognitive interview?
The cognitive interview was originally developed by Fisher and Geiselman.
What are the four principles of the cognitive interview?
1) Context reinstatement or mental reinstatement
2) Report everything
3) Recall in changed order
4) Recall from changed perspective
What occurs during the context reinstatement?
- Witness is encouraged to mentally recreate the environment and how they were feeling at the time of the event
- E.g “Try to remember the context of the event in question. Recall the scene, weather, how you were feeing.”
- There is mental consistency between the actual incident and the recreated situation
- Increased likeliness that the witness will recall more details
What occurs during report everything?
- Report every detail about the event that you can recall even if it seems trivial and unimportant
- Information should be reported even if it does not seem to have a bearing on the crime
- This unrestrained recall may throw up details, which might otherwise be inadvertently mentally ‘edited out’
- It is the interviewers responsibility to decide what is important
What occurs during recall from changed perspective?
- The witness is asked to mentally recreate the situation from a different perspective
- Describing the event from another viewpoint
- Prevents the use of schemas
What occurs during recall in reverse order?
- The witness is encouraged to describe the event in reverse order or to start with an aspect of the scene which seems most memorable and work backwards
- Prevents the use of schemas
Give strengths of the cognitive interview.
1) Cognitive interview improves recall
- There is research that suggests that techniques employed by the cognitive interview improve recall
- For example, Milne and Bull found in particular a combination of report everything and context reinstatement produced better recall than the standard police interview.
- The cognitive interview appears to be an improvement from the standard police interview. This is demonstrated by report everything and context reinstatement producing better recall of events
- Therefore, even a shortened version of CI still results in more accurate recall from witnesses, which can be used to improve police interviews of eyewitnesses’ accounts
2) Produces more accurate recall than standard police interview
- A strength of the cognitive interview is that it produces the most accurate recall in comparison to other interview methods
- For example, Geiselman et al. showed participants simulated violent crimes. 48 hours later witnesses were interviewed about the films, using cognitive interviews, a standard police interview, or an interview using hypnosis.
- The cognitive interview elicited the most accurate recall.
- This indicates the cognitive interview is the most accurate interview method and can be used to enhance recall of witnesses better than other interview techniques
- Therefore, this demonstrates that the cognitive interview is the most effective interview method, which potentially could be used with greater success in the real
Give limitations of the cognitive interview.
1) Cognitive interview is very time consuming
- A limitation of the cognitive interview is that it is very time consuming
- Time is needed to establish rapport with a witness and allow them to relax.
- The CI also requires time for special training which many police forces have not been able to provide
- The cognitive interview may not suitable in certain situations because of the associated time constraints, which is why Police may be reluctant to use CI
- Therefore, some police forces may not carry out a complete CI, reducing its overall effectiveness
2) There is an increase in inaccurate research
- The cognitive interview can encourage witnesses to recall inaccurate information
- Kohnken et al. carried out a meta-analysis of 55 studies and found an 81% increase of correct information but also a 61% increase of incorrect information when compared to a standard police interview
- This revealed that CI may encourage witnesses to recall more false information
- Therefore, the cognitive interview produces inaccurate information, which questions the accuracy of the interview procedure in collecting eyewitness testimonies
