Studied by 20 people
Outline the multi store model of memory
Information reaches our senses from the environment and enters our memory system through the sensory register where it registers for only very brief periods. The capactity of the sensory register is very large, the duration is half a second and its coding is sensory specific/unprocessed. Some of the information from the sensory register is picked up by the process of attention and passes through to the STM. Information can be kept indefintely in STM through maintenance rehearsal. STM has a capoacity of 7 +/- 2 items, a duration of 30 seconds and is coded acoustically. If we think about the meaning of the information in STM, a process known as elaborative rehearsal, the information becames encoded semantically and passes to the LTM store where the capacity is unlimited, the duration is lifelong and the coding is semantic. Atkinson and Shiffrin’s MSM claims that each memory store is unitary and that STM and LTM are separate stores located in different areas of the brain (therefore even if one store is damaged, the others remain intact).
What are the evaluation points of the MSM
+ Research from Glanzer & Cunitz supports the claim that STM and LTM are seperate stores
- Flash bulb memories
+ Supported by Clive Wearing’s real life case study
- Not fully supported by Clive wearing’s real life case study
+ Research from Glanzer & Cunitz supports the claim that STM and LTM are seperate stores
A strength of the MSM is that there is research to support the claim that STM and LTM are seperate stores. Glanzer & Cunitz asked ppts to remember a list of words and found that when ppts were asked to recall them, they were more likely to recall words from the beginning and the end of the list. The words at the start are linked to the LTM (primacy effect) and the words at the end are linked to the STM (recency effect). This is a strength because the research demonstrates that LTM and STM are two seperate stores as the MSM claims, giving both the claim and the explanation of how memory works validity.
- Flash bulb memories
A limitation of the MSM is that it overemphasises the role of rehearsal in forming LTM’s. Many psychologists believe that rote rehearsal is too simple a process to account for the transfer of information from the STM to the LTM and instead it often occurs with no rehearsal. For example ‘flashbulb memories’ can be recalled very easily without rehearsal. This is a limitation because material doesn’t always pass from STM to the LTM by being rehearsed in the way that the MSM suggests, therefore weakening the validity of the MSM as an explanation of how memory works.
+ Supported by Clive Wearing’s real life case study
A strength of the MSM is that it is supported by the real life case study of Clive Wearing whose memory restarted once the time span of his STM elapsed (every 30 seconds), showing that his STM was intact. However his LTM is damaged which is evident due to his inability of being able to recall his LTM’s eg the names of his children. This is a strength because his case demonstrates that even if one store is damaged (LTM), the other still remains intact (STM), adding validity to the claim that the memory stores are unitary. However his case is unique so the findings should be generalised to the population with caution.
- Not fully supported by Clive wearing’s real life case study
A limitation of the MSM is that it is not fully supported by the real life case study of Clive Wearing as he has some LTM’s but not others. For example, he can’t recal recieving a musical education (episodic memory) but can still play the piano (procedural memory). This is a limitation because the findings suggest that LTM is not a unitary store, contradicting MSM’s claim of the memory stores being separate and therefore weakens its claim.
What are the feautures of each memory store?
Capacity
Duration
Coding
Define capacity
The amount of information a store can hold at any one time
Define duration
The length of time information can be held in memory
Define coding
The format in which information is stored
What are the features of the sensory register?
Memory store for each of our 5 senses: sight, smell, touch, hear and taste
Enables us to remember sensory stimuli after our exposure to the stimuli has ended
Sensory stores in the sensory register:
Iconic - visual information
Echoic - auditory information
Haptic - feel
Gustatory - taste
Olfactory - smell
Capacity - very large
Duration - half a second
Coding - sensory specific/unprocessed
If you pay attention to the information, passes through to the STM
If you don’t pay attention to the information, then it fades - ‘trace decay’
Outline Sperling’s research into the capacity and duration of the sensory register
Sperling aimed to investigate the capacity and duration of the sensory register. Ppts were flashes a 3×4 grid of letters onto a screen for 50 milliseconds. Their task was to recall as many letters as they could remember. Ppts were also asked to recall single rows of letters when particular tones were heard (high tone = top row & medium tone = middle row). When ppts were asked to recall as many letters as possible, they could remember approximately 4. When asked to recall single rows of letters, ppts recalled an average of 3 items, however these decaued rapidly. It was concluded that the capacity of the sensory register is a minimum of 4 items (but it could be much more) and the duration is between250 to 500 milliseconds.
What are the evaluations of Sperling’s research into the capacity and duration of the sensory register
+ High control
- Low ecological validity
+ High control
A strength of Sperling’s research is that it is a lab experiment and therefore has high control over extraneous variables. All the ppts had the same experience - all were shown the same letters for the same amount of time and given the same standardised instrcutions in a highly controlled environment. This is a strength because the results are unlikley to be affected by confounding variables and we can therefore be confident that the claim that the duration of sensory memory is limited and the capacity is large is internally valid.
- Low ecological validity
A limitation of Sperling’s study is that it has low ecological validity. In Sperling’s research, ppts were shown random letters in an unfamiliar controlled environment and were asked to recall them which is an artificial and unrealistic task. This is a limitation because the findings may be difficult to generalise to how sensory memory works in real life and therefore has low external validity.
What are the features of STM?
Capacity - 7 +/- 2
Duration - 18-30 seconds
Coding - Acoustic
Outline Millers digit span study into the capacity of STM
Miller aimed to investigate the capacity of STM by using the digit span technique. The technique consists of ppts hearing a list of numbers and immediately trying to recall them in correct order. Miller reviewed psychological research and concluded that the capacity of STM is 7 +/- 2. He also found that chunking information together meant that we could remember more (eg mobile nimbers can be split into 3 digits, leaving more memory caoacity available).
What are the evaluation points for Millers digit span study into the capacity of STM
+ High control
- Individual differences
+ High control
A strength of Millers research into the capacity of STM is that it was conducted using a lab experiment and can therefore establish cause and effect. As this experiment has high control over extraneous variables, we can be confident that the IV (how many numbers the list consisted of) affected the DV (accurate recall of the number list in the correct order). This is a strength because the results of the study are unlikely to be affected by confounding variables and we can therefore be confident that the capacity of STM is 7 +/- 2.
- Individual differences
A limitation of the claim that STM can hold 7 +/- 2 pieces of information is that there are individual differences in mememory capacity depending on factors such as age. Jacobs found that digit span increased with age: 8 year olds - 6.6 digits and 19 year olds - 8.6 digits. He also found that people find it easier to remember numbers rather than letters as the average span for letters was 7.3 and for numbers it was 9.3. This is a limitation because the assumption that capacity of all individuals STM is 7 +/- 2 is over simplistic and may not generalis to how everybody’s STM works.
Outline Peterson & Peterson’s trigram study into the duration of STM
Peterson & Peterson presented 24 undergraduates with a consonant trigam. Rehersal was prevented by asking ppts to count backwards in threes from a specified number. After intervals of 3, 6, 9, 12, 15 or 18 seconds to over 30 seconds, ppts were asked to stop counting and to repeat the trigram. After 3 seconds 80% of the trigrams were recalled correctly. After 18 seconds less than 10% of the trigrams were recalled correctly. After 30 seconds no trigrams were recalled. They concluded that the duration of STM is 30 seconds or less if maintenance rehearsal is blocked. This information fades from STM because of trace decay.
What are the evaluation points of Peterson & Peterson’s trigram study into the duration of STM
+ High control
- Low ecological validity
+ High control
A strength of Peterson and Peterson’s study into the duration of STM is that it was conducted in a lab experiemnt and can therefore establish cause and effect. As this experiment had high control over extraneous variables (eg all ppts were given the same standardised instructions and the same trigrams were shown for the same length of time) we can be confident that the IV (time intervals blocking maintenance rehearsal) affected the DV (accurate recall of constonant trigrams). Strength because the results of the study are unlikely to be affected by confounding variables and we can therefore be confident that the conclusion that the duration of STM is 18-30 seconds has high internal validity.
- Low ecological validity
A limitation of Peterson and Petersons research is that it has low ecological validity. Ppts were presented with a trigram in an unfamiliar controlled environment, and recalling it is an artificial and unrealistic task which doesn’t test the true complexity of memory. This is a limitation because the results that STM has a duration of 18-30 seconds may not be bale to be generalised to how STM works in real life and therefore has low external validity
What are the features of LTM?
Capacity - Unlimited
Duration - Lifelong
Coding - semantic
Outline Bahrick’s photo year book study into the duration of LTM
392 graduates from a highschool in America over a 50 year period were shown a set of photographs from their highschool yearbook and ppts were split into 2 groups. Group 1 was the photo recognition group where ppts were given a list of names and asked to select the name that matched the person in the photo. Group 2 was the recall group where ppts were simply asked to name the people in the photos (they weren’t given a list of names). Bahrick found that in the photo recognition group, at 15 years 90% could accurately match the correct name to the person in the photo but at 48 years only 70% could. In the recall group, at 15 years 60% could accurately name the people in the photos but at 48 years only 30% could. It was concluded that the duration of LTM can last a long time.
What are the evaluation points of Bahrick’s photo year book study into the duration of LTM
+ High ecological validity
- Low control
+ High ecological validity
A strength is that it has high ecological validity. The study used meaningful stimulus material (high school yearbooks) and tested people for memories from their own lives. This is a strength because it provides valuable real-life evidence to suggest that the duration of LTM is life long and therefore has high external validity.
- Low control
A limitation of the study is that it has low control over extraneous variables. It is possibile that ppts identification of their classmates might have been affected by external factors eg if ppts had met their old classmates more recently than when they left high school. Limitation because Bahrick’s conclusion might not have had high internal validity and be considered as weak evidence into duration of LTM.
Outline Baddeley’s research into the coding of STM and LTM
Baddeley aimed to investigate coding in LTM and STM. He divided ppts (British housewives) into 4 conditions. Each condition were shown a list of 10 words that were either:
A) accoustically similar
B) accoustically dissimilar
C) semantically similar
D) semantically dissimilar
In the STM study, ppts were asked to immediately recall the 10 words they had heard in correct order. In the LTM study ppts were given an interval of 20 minutes to complete another task before being asked to recall the 10 words in the correct order. Baddeley concluded that coding in STM was acoustic as ppts recall was much worse for accoustically similar words as they got confused and muddled up unlike accoustically dissimilar words. He also concluded that coding in LTM was semantic as ppts recall was much worse for semantically similar words as they got distracted by semantic similarities and muddled them up unlike semantically dissimilar words.
What are the evaluation points for Baddeley’s research into the coding of STM and LTM
+ High control
- Low ecological validity
+ High control
A strength is that the study is a lab experiment and can therefore establish cause and effect. As lab experiments have high control over extraneous variables, we can be confident that the IV (accoustically/semantically dissimilar/similar word lists) affected the DV (accurate number of words recalled). This is a strength because the findings are unlikely to be affected by confounding variables so we can be confident thart coding in LTM is semantic and in STM it is acoustic - finding are internally valid.
- Low ecological validity
A limitation is that the study has low ecological validity. Recalling a list of words is an artificial and easy task which does not test the true complexity of memory. This is a limitation because Baddeley’s findings cannot necessarily be generalised to real life (low external validity) and therefore might not provide valid support for the claim that information is usually coded semantically in LTM and accoustically in STM.
Outline the WMM
The WMM was proposed by Baddeley and Hitch as a development to the MSM. They believes that STM is a dynamic system which actively processes information. It is not a unitary store but instead consists of seperate components.
The most important component is the central executive as it is the organiser of STM. It plays a key role in problem solving and decision making as it attends all incoming information and decides what pieces of information to allocate to the slave systems. It is modality free as it encodes information in all sensory forms. However it has a limited storage capacity and can therefore only deal with one type of information at a time.
Another component of the WMM is the phonological loop which deals with auditory information and is therefore active during verbal tasks. It is encoded acoustically and has limited storage capacity. It is subdivided into the phonological store which stores acoustically coded items for brief periods and the articulatory loop that allows sub-vocal repetition (maintenance rehearsal) of the items in the phonological store.
Another component is the visuo-spatial sketchpad which stores/manipulates visual and spatial information. It is subdivided into the visual cache which stores visual data and the inner scribe which records the arrangement of objects in the visual field. The VSS has limited capacity and is encoded visually.
In 2000 Baddeley proposed an additional component, the episodic buffer. It has limited capacity but is responsible for integrating and manipulating material from all the components and recalls material from LTM and integrates it into working memory.
What are the evaluation points for the WMM
- Little is known about the central executive
+ Supported by research using PET scans
+ Supported by KF
+ Supported by research using the dual task technique
- Little is known about the central executive
A limitation of the WMM is that very little research has been conducted on the central executive and we therefore have limited evidence for its role in STM. It is extremely hard to study so we can’t be sure that it does indeed monitor and coordinate the slave systems in the way the WMM suggests. This is a limitation because the claims made by Baddeley and Hitch about the central executive may not be valid.
+ Supported by research using PET scans
A strength of WMM is that it is supported by research using PET scans which have shown brain activity occuring in different areas when individuals carried out visual tasks (eg mentally counting the windows in a house) and auditory tasks (eg repeating words). This brain activity corresponds with the four systems that the WMM proposes. This is a strength because it provides emperical evidence to suggest that STM does have different components as the WMM suggests.
+ Supported by KF
A strength of the WMM is that it is supported by the case study of KF who suffered brain damage after a stroke following a motorcycle accident that affected his STM. KF had poor short term memory ability for auditory information but could process visual information normally. For instance, his immediate recall of letters and digits was better than whe he read them (visual) than when they were read to him (acoustic). This suggests that his PL had been damaged, but his VSS was intact. This supports the WMM as a valid explanation of memory as it supports the existence of seperate visual and acoustic stores as the model suggests. However his case is unique so findings should be generalised to the population with caution.
+ Supported by research using the dual task technique
A strength of the WMM is that it is supported by research using the dual task technique. Baddeley et al found that ppts could successfully track a spot of light and complete a verbal task at the same time (using the VSS and the PL). However, ppts were less successful when asked to track the spot of light and describe the letter F (tasks both use the VSS). This supports the WMM as a valid explanation of memory because it supports the claim that STM is not unitary, but instead consists of seperate components that have limited capacity.
What are the different types of LTM?
Episodic
Semantic
Procedural
What is episodic memory?
LTM store for personal events. Includes memories of when the events occurred and of the people, objects, places and behaviours involved. Memories have to be retrieved consciously and with effort (explicit). Located in the temporal lobe. Memories are declarative and less resistant to forgetting/amnesia.
What is semantic memory?
LTM store for our knowledge of the world. Includes facts and our understanding of what words and concepts mean. Memories have to be retrieved consciously and with effort (explicit). Located in the temporal lobe. Memories are declarative less resistant to forgetting/amnesia.
What is procedural memory?
LTM store for our knowledge of actions and skills. Includes our memories of learned skills. Memories can be recalled without making a conscious or deliberate effort (implicit). Located in the cerebellum and motor cortex. Memories are non-declarative more resistant to forgetting/amnesia.
What are the evaluation points into the types of LTM?
+ Case study of Clive Wearing
- Low population validity
+ Supported by PET scans
+ Case study of Clive Wearing
A strength of the claim that we have different types of LTM is that it is supported by the real life case study of Clive Wearing. He knew what a piano was (semantic memory) and how to play one (procedural memory) but was unable to remember recieving piano lessons (episodic memory). Therefore Clive Wearing’s case study provides strong evidence to support the claim that LTM is not a unitary store, but instead consists of separate systems.
- Low population validity
A limitation of the supporting research that we have different types of LTM is that it has low population validity. The sample consists of one British man - Clive Wearing. Case studies are unique cases and therefore may not be representative of all individuals in the population. Therefore the findings that LTM is divided into three different systems (from the case study of Clive Wearing) may be difficult to generalise to other people and has low external validity.
+ Supported by PET scans
A strength of the claim that we have different types of LTM’s that are stored in different areas of the brain is that it is supported by research using PET scans. Tulving asked ppts to peform various memory tasks while their brains were scanned using a PET scanner. They found that episodic memories were associated with increased blood flow in the frontal lobes of the cortex and semantic memories were associated with increased blood flow in the posterior region of the cortex. This is a strength because it demonstrates that LTM is separated into different stores and that they are located in different areas of the brain. Moreover, the findings have been repliacted many times in later research studies, which further supports the validity of this finding.
Outline Tulvings study into the types of LTM
Tulving aimed to investigate if episodic and semantic tasks were processed differently. 6 ppts were injected with radioactive gold which would be detected in the body using a gamma ray detector. Ppts then thought about semantic memories such as ideas they have learnt from a book or episodic memories such as their school days. Ppts would start thinking about a topic and 60 seconds later they woukd be injected with the gold. They were then scanned 8 seconds later when the gold would have got to their brains. They found that the two different types of tasks provided different patterns of blood flow in the brain. Episodic memories were associated with increased blood flow in the frontal lobes of the cortex and semantic memories were associated with increased blood flow in the posterior region of the cortex. Tulving concluded episodic and semantic LTM’s involve different parts of the brain and are therefore separate parts of the LTM. This suggests a biological basis for differences in the LTM.
What are the evaluation points for Tulvings study into the types of LTM?
+ High control
- Low internal validity
- Small sample size
+ High control
Tulvings study is a lab experiment and therefore establishes cause and effect. Lab experiments have high control over extraneous variables so we can therefore be confident that it was the IV (whether ppts recalled semantic or episodic memories) that affected the DV (the location of increased blood flow in the brain). This is a strength of the study becuase the results are unlikely to be affcted by confounding variables and we can therefore be confident that the conclusions that episodic and semantic LTM’s involve different parts of the brain and are separate parts of the LTM are internally valid.
- Low internal validity
A limitation of Tulvings tsudy into the types of LTM is that it involves asking ppts to think about semantic or episodic memories in order to track where bloof flows in their brain to demonstrate that different LTM are stores in separate areas. However there is no way to be sure that ppts are actually recalling those memories at that time. This is a limitation because the findings of the study that LTM does involve different parts of the brain would not be internally valid.
- Small sample size
A limitation of Tulving’s research is that it has low population validity. The sample consisted of 6 ppts which is a very small sample size and therefore may not be representaive of how all individuals LTM work. This is a limitation because it may be difficult to generalise the findings that LTM does use different areas of the brain to other people (low external validity).
What are the two explanations of forgetting?
Proactive and retroactive interference
Retrieval failure due to the absence of cues
Define interference
Forgetting because one memory blocks the recall on another, causing one or both memories to be forgotten. The degree of forgetting is often greater when the memories are similar.
What is proactive interference?
Forgetting occurs when old memories (already stored) disrupt the recall of new memories. The degree of forgetting is greater when the memories are similar.
Give an example of proactive interference?
The teacher has learnt so many old names from the past that she finds it difficult to remember the names of her current student.
What is retroactive interference
Forgetting occurs when new memories distrupt the recall of old memories (already stored). The degree of forgetting is greater when the memories are similar.
Give me an example of retroactive interference
The teacher has learnt so many new names that she finds it difficult to remember the names of her students from last year
Outline Postmans study into retroactive interference
Postman aimed to investigate how retroactive interference affects learning. In a lab experiment, ppts were split into two groups. Both groups had to remember a list of paired words however the experimental group also had to learn another list of words where the second paired word was different. The control group was not given a second list. All ppts were asked to recall the words from the first list. Postman found that the recall of the control group was more accurate than that of the experimental group. This suggests that learning items in the second list interfered with ppts ability to recall the original list. This demonstrates retroactive interference.
Outline Keppel & Underwood’s study into proactive interference
Keppel and Underwood examined the the effect of proactive interference on LTM, in an experiment that resembles Peterson and Peterson. Ppts were presented with consonant trigrams at different intervals (3, 6, 9 etc). To prevent rehearsal ppts were asked to count backwards in threes before recalling. Ppts were asked to come back at later stages where they would partcipate in a few trials of the task, involving learning new trigrams. They found that ppts were able to recall the trigrams that were presented first, irrespective of the interval lengths. However it was found that they were poor at recalling later trigrams as earlier learning of trigrams had interfered with later learning. They concluded that proactive interference had occurred as the memory for the earlier consonants interfered with the memory of new consonants.
What are the evaluation points of interference?
- Studies that support interference tend to be lab based
- Only explains forgetting when information is similar
+ Retroactive interference - supported by Postman’s research
+ Proactive interference - supported by Keppel & Underwood’s research
- Studies that support interference tend to be lab based
A limitation of interference is that studies that support the theory tend to be lab based and therefore have low ecological validity. For example, Keppel and Underwood’s study involved ppts recalling trigrams at different time intervals and Postman’s involved ppts memorising paired word lists. This is a limitation because the tasks are not everyday tasks and are artificial and unrealistic and therefore do not test the true complexity of memory. This is a limitation of interference because the theory may not be a valid explanation of forgetting in the real world - low external validity.
- Only explains forgetting when information is similar
A limitation of the interference theory is that it only explains forgetting when two sets of information are similar. For example, it can only explain why we find it difficult to learn french when we already know german however this does not happen very often. This is a limitation because the interference theory cannot explain most of the times we forget information; it can only be applied to very specific situations.
+ Retroactive interference - supported by Postman’s research
A strength of the retroactive interference explanation of forgetting memory is that it is supported by evidence using a lab experiment. For example, Postman asked ppts to learn a list of word pairs.They found that the recall of the original list was worse when ppts were also asked to learn another list compared to a control group who weren’t asked to learn the second list. This is a strength because the findings demonstrate that forgetting occurs when one memory blocks another as the theory claims, making it valid.
+ Proactive interference - supported by Keppel & Underwood’s research
A strength of the proactive interference explanation of forgetting memory is that it is supported by evidence using a lab experiment. For example, Keppel & Underwood found that ppts were able to remember trigrams well in the first trials they had to undertake to learn them. When ppts came back for later trails to learn new trigrams, they were very poor at recalling them. This demonstrates proactive interference as the trigrams in the later trials were not recalled well as the earlier learning of trigrams interfered with the later learning. This is a strength of interference because the findings demonstrate how forgetting occurs when one memory blocks another as the theory claims, giving it validity.
Define retrieval failure
A form of forgetting - it occurs when we dont have the necessary cues to access memory. The memory is available but not accessible unless a suitable cue is provided.
What is a cue?
A ‘trigger’ of information that allows us to access a memory. Such cues may be meaningful or may be indirectly linked by being encoded at the time of learning.
Can be external (environmental context) or internal (state of mood)
Outline the retrieval failure theory of forgetting
People may forget information due to the absence of cues. When information is initially placed in memory, associated cues are stored at the same time. If a cue is to help us recall information it has to be present at encoding and also at at retrieval. If the cues available at encoding and retrieval are different or absent, then there will be some forgetting. Some cues are linked to material to be remembered in a meaningful way - mnemonic techniques.
What are the three types of cues that are encoded at the time of learning
material
context-dependent forgetting (external)
state-dependent forgetting (internal)
Describe context-dependent forgetting
Relevant cues in the environment that were present at the time of learning the information are missing from the place you then recall the information in.
Give me an example of context-dependent forgetting
You used a certain pen to write information down whilst revising for an exam, however you don’t use the same pen in the exam - less likely to remember the information
Who studies context-dependent forgetting?
Godden and Baddeley
Describe state-dependent forgetting
There are psychological and physiological differences between how you felt when you were learning the information and then when you later recalled the information, which may affect recall.
Give me an example of state-dependent forgetting
Bowers findings:
Felt happy when learning the information, felt sad when recalling the information - less likely to remember
Felt happy when learning the information, felt happy when recalling the information - more likely to remember
Who studies state-dependent forgetting?
Darley et al
Outline Godden & Baddeley’s study into context-dependent forgetting
Godden and Baddeley aimed to investigate whether ppts recall would be affected if they had to recall the information in a different context to where it was first learnt. Divers learnt a list of words either on land or underwater. They were then asked to recall the list of words on land or underwater. Therefore there was 4 conditions:
learned on land - recall on land (matching)
learned underwater - recall underwater (matching)
learned on land - recall underwater (non-matching)
learned underwater - recall on land (non-matching)
They found that accurate recall of the list of words was 40% lower in the non-matching conditions. They concluded that when the external cues available at learning are different from those at recall, this leads to retrieval failure.
Outline Darley’s study into state-dependent forgetting
Darley aimed to investigate state-dependent forgetting. Ppts smoked cannabis and were then asked to hide some money whilst high. They were then asked to find the money again whilst some of them were still high and others were no longer high. Darley found that the ppts who were still under the influence of cannabis were more successful in finding the money than the ppts who were sober. They concluded that the psychological/physiological state that you are in when coding the information must be similar to that of when recalling the information in order to be successful. Therefore if state is different, you’re more likely to forget.
What are the evaluation points of retrieval failure due to the absence of cues
- Supporting research has low ecological validity
+ Real life application - cognitive interviews
+ Supported by research - G&B and Darley
- Low population validity - Godden and Baddeley
- Supporting research has low ecological validity
A limitation of the retrieval failure theory of forgetting is that the supporting research has low ecological validity. For instance, Godden and Baddeley’s study used an artificial task of learning a list of words underwater and having to recall the list of words underwater which is not an everyday task. This is a limitation because we have very limited real life evidence to support the retrieval failure theory and therefore it may not provide a valid explanation for forgetting in real life.
+ Real life application - cognitive interviews
A strength of the retrieval failure theory of forgetting is that it has practical applications. For example, Baddeley suggests that reinstating context in which the information was first encoded helps us to remember when we have trouble doing so. This is demonstrated in cognitive interviews to help eyewitnesses remember crucial information and can also help students remember information in exams. This is a strength of the retrieval failure theory of forgetting because it makes a useful contribution to the real world.
- Low population validity - Godden and Baddeley
A limitation of Godden and Baddeley’s research is that it has low population validity. The sample was small as it consisted of 18 divers and therefore there is only a small amount of data to draw conclusions from. In addition the results may not be able to be generalised to those who are non-divers. This is limitation because the confidence in the conclusions drawn as valid are reduced because of the limited data.
+ Supported by research - G&B and Darley
A strength of the context-dependent theory and state-dependent theory of forgetting is that it has supporting research. For instance, Godden & Baddeley carried out a study where they aimed to investigate whether ppts recall would be affected if they had to recall the information in a different context to where it was first learnt and found that when the external cues available at learning was different from those at recall, this lead to retrieval failure. Moreover, Darley aimed to investigate state-dependent forgetting and found that when the psychological/physiological state when learning information was different to when recalling the information, retrieval failure was more likely. This is a strength because both study’s demonstrate that forgetting can occur when a cue whilst learning the information isn’t present at the time of recall, giving the retrieval failure theory of forgetting validity.
Define eyewitness testimony
The ability of people being able to remember the details of events such as accidents and crimes that they themselves observed. Accuracy of EWT can be affected by factors such as misleading information and anxiety.
What are the factors affecting EWT
Misleading information - leading questions and post-event discussion
Anxiety
Define misleading information
Incorrect information given to the eyewitness usually after the event (aka post-event information). Can take many forms such as leading questions and post-event discussion between co-witnesses or other people.
Define leading questions
A question which because of the way it’s worded suggests a certain answer.
Outline Loftus and Palmers study into misleading information (leading questions)
Loftus and Palmer aimed to investigate whether misleading information distorts the accuracy of an eyewitness’ immediate recall. 45 students ppts were all shown the same 7 films of different accidents in a lab experiment. After each film, ppts were asked to describe the accident in a questionnaire followed by a series of specific questions, including the critical question “How fast were the cars going when they ______ into each other?” Ppts were split into 5 conditions, taking part in only one each. Every condition had a different verb in the critical question: smashed, collided, bumped, hit and contacted. They found that the estimated speed for ‘smashed’ was 40.8, ‘collided’ was 39.9, ‘bumped’ was 38.1, ‘hit’ was 34 and ‘contacted’ was 31.8. They concluded that the form of questioning can have an effect on witness’ memory. Leading questions can cause material to be altered, therefore making memory less accurate.
What are the evaluation points for Loftus and Palmers study into misleading information (leading questions)
+ Lab experiment - high control
+ Practical application
- Low population validity
- Low ecological validity
+ Lab experiment - high control
A strength of Loftus and Palmer’s study is that it is a lab experiment and therefore establishes cause and effect. Lab experiments have high control over extraneous variables (eg all ppts heard the same standardised instructions and watched the same video clips) so we can be confident that it was the IV (the verbs used in the critical question that affected the DV (ppts estimates of speed). This is a strength of the study because the results are unlikely to be affected by confounding variables and we can therefore be confident that the findings that leading questions reduce the accuracy of EWT have internal validity. Therefore this supports the theory that misleading information does reduce the accuracy of EWT.
+ Practical application
A strength of the research is that it has practical applications. For example, we now understand that misleading information can distort EWT, meaning that its not always accurate and therefore when witnesses are interviewed, police now avoid leading questions. In addition, Loftus and Palmer’s research has led to the development of cognitive interviews which increases the accuracy of EWT because the style of questions they use reduces opportunities for leading questions to be used. This is a strength of the research because it has made a valuable contribution to how the legal system works in real life. In addition, it also has economic implications because if EWT is more accurate, this means that there are less incorrect convictions, therefore less appeals. This results in more money being saved in the criminal justice system.
- Low population validity
A limitation of the research into misleading information is that it has low population validity. For example the sample consisted of American undergraduate students. These individuals may have less driving experience than others, be tested more regularly and also may be more likely to affected by demand characteristics if they are aware of the nature of Loftus and Palmer’s work through being at the university. This is a limitation because the findings of the study can’t necessarily be generalised to other people and has low external validity and therefore may not provide valid support for the claim that leading questions reduce the accuracy of EWT.
- Low ecological validity
A limitation of the research is that it has low ecological validity as the method does not test the impact of leading questions on the accuracy of EWT in a realistic meaningful way. The ppts watched a video of a car accident and therefore were unlikely to respond in the same way they would have done if the car accident was real eg they were not distressed and there was also no consequences for the perpetrator based on the ppts answers. This is a limitation because the results can’t necessarily be generalised to real life (low external validity) and therefore may not provide valid support for the claim that leading questions reduce the accuracy of EWT. Furthermore Yuille and Cutshall’s research into leading questions and EWT using real life witnesses of a crime found that leading questions had no effect upon the accuracy of recall. This suggests that in real life, when there is high ecological validity, misleading information does not make EWT less accurate.
Outline Gabbert et al’s study into misleading information (post-event discussion)
Gabbert et al aimed to investigate the effect of post-event discussion as a factor affecting the accuracy of EWT. Ppts watched a video of the same crime, but filmed from different points of view. They were then asked to either discuss the video they had just seen or have no discussion (control group). They found that 71% of ppts who had a discussion reported aspects of the event they did not see in the video but picked up from the discussion whereas in the control group, this figure was 0%. They concluded that witnesses often go along with each other, either to win social approval (NSI) or because they believe that the other witnesses are right and they themselves are wrong (ISI) - they called this memory conformity.
What are the evaluation points of Gabbert et al’s study into misleading information (post-event discussion)
+ Practical application
+ Lab experiment - high control
- Low ecological validity
+ Practical application
A strength of the research into post-event discussion is that it has practical applications. For example, from the research we now understand that EWT is not always accurate and that post-event discussion can distort EWT and therefore police should aim to avoid witnesses talking to each other. This is a strength because it has made a valuable contribution to our understanding of the issue of using EWT as evidence in criminal investigations in real life.
+ Lab experiment - high control
A strength of Gabbert’s study is that it is a lab experiment and establishes cause and effect. Lab experiments have high control over extraneous variables so we can be confident that it was the IV (discussion about the video or no discussion) that affected the DV (% of ppts that provided information that they did not witness). This is a strength because the results are unlikely to affected by confounding variables and we can therefore be confident that the findings that post-event discussion reduces the accuracy of EWT has internal validity.
- Low ecological validity
A limitation of Gabbert’s research is that it has low ecological validity. For example, ppts watched a video of a crime and therefore were not likely to respond in the same way as they would if they had witnessed the crime in real life eg less anxious and distressed. This is a limitation because results can’t be generalised to real life (low external validity) and therefore may not provide valid support for the claim that post-event discussion reduce the accuracy of EWT.
Define anxiety
A state of emotional and physical arousal. The emotions include having worried thoughts and feelings of tension. Physical changes include an increased heart rate and sweatiness. Anxiety is a normal reaction to stressful situations, but can affect the accuracy and detail of EWT.
Outline anxiety as a factor affecting the accuracy of EWT
The ‘Yerkes Dodson Law’ proposes that very high and low levels of arousal (such as anxiety) reduces accuracy of EWT. It suggests that moderate anxiety is associated with better recall than very high or very low anxiety.
The weapon focus effect occurs because presence of a weapon focuses attention away from less dramatic visual images such as the face of the perpetrator. Weapons attract attention because they pose as a threat and may cause emotional arousal and anxiety. The weapon focus reduces the ability of the witness to provide accurate identification.
Outline Johnson and Scott’s study into anxiety affecting EWT
Johnson and Scott aimed to investigate if the presence of a weapon (which leads to anxiety) affects the accuracy of EWT. Ppts were asked to sit in a waiting room where they heard an argument in an adjoining room and then saw a man running through the room carrying either a pen covered in grease (low anxiety condition) or a knife covered in blood (high anxiety ‘weapon focus’ condition). Ppts were later asked to identify the man from a set of photographs. The findings support the idea of the weapon focus affect accuracy. The mean accuracy was 49% in identifying the man in the pen condition, compared to 33% accuracy in the knife condition. Loftus et al showed that anxiety does focus attention on the central features of a crime (eg the weapon). Eyewitnesses eye movements were monitored and they found that the presence of a weapon caused attention towards the weapon, taking it away from other things such as the persons face. They concluded that weapon focus leads to less accurate recall of the person committing the crime because of the anxiety that the witness experiences.
Note 
Flashcard (59)