Memory: MSM, WMM, LTM Types, EWT, Forgetting and Interference Flashcards
What format is coding in STM?
acoustic
What format is coding in LTM?
semantic
Who discovered the encoding in LTM and STM? What were their findings?
Baddely (1966) found more mistakes are made recalling acoustically similar words immediately after learning them, and recalling semantically similar words 20 minutes after learning them
What is the capacity of STM thought to be? Who are the two relevant researchers?
7+-2 chunks (so we can remember 7 groups of things rather than 7 things). Jacobs (1887) conducted digit span tests and Miller (1956) published an article with the 7 chunks theory.
What is the capacity of LTM thought to be?
unlimited
What did Jacobs (1887) do? Findings?
Digit span test to find capacity of STM for numbers and letters. Used 443 female students who had to repeat back a string of digits/letters in the same order as it was read to them until they could no longer recall the sequence.
Average of 7.3 letters.
Strength of Miller’s research/article?
Supported by research (Jacobs 1887, then explain procedure and results)
2 problems with Miller’s research?
Didn’t specify how large a chunk should be so we can’t conclude exact capacity, further research required to determine this.
Didn’t take into account other factors that affect capacity like age, which Jacobs research acknowledged that STM changes with age.
What is the duration of STM thought to be?
18-30 seconds.
Who demonstrated duration of STM, and procedure?
Peterson and Peterson (1959) found that increasing retention intervals decreased accuracy of recall of syllables. Mental rehearsal was prevented as they had to count down from a 3 digit number.
What is the duration of LTM thought to be?
Lifelong/Unlimited
Who demonstrated duration of LTM? what was the procedure?
Bahrick et al (1975) showed 392 US uni graduates photos from high-school yearbooks and asked to select the name that matches the photo.
Bahrick et al results.
90% could match after 14 years. 60% could match after 47 years.
Bahrick et al conclusion.
Concluded people could remember some information for a very long time, potentially lifetime but at least 47 years, and is semantically encoded.
Bahrick et al criticism (2 points)
Lacks population validity (392 US graduates). Unable to generalise results to other populations.
Doesn’t explain why LTM is less accurate overtime - limited duration or affected by age. Means psychologists can’t determine if LTM has unlimited (but affected by age) or limited duration.
Strength of Bahrick’s research (1 point).
High levels of ecological validity as it used real life memories, reflecting our memory for real life events and can be applied to everyday memory. Use of meaningful stimuli.
Peterson and Peterson + Miller et al criticism.
Low mundane realism due to use of artificial stimuli (little personal meaning). This means little ecological validity so not reflective of real life memory and learning experience, limiting generalisability.
High mundane realism means high:
ecological validity
Key issue with Jacobs (and all historical research)
Lack of standardisation and use of scientific methods, producing less reliable results due to confounding variables and lower control.
What are the 3 stores in the MSM
sensory register, STM, and LTM
Sensory register MSM features
A sub-store for each sense, huge capacity, duration of less than half a second
Process that passes info from SR to STM
attention
STM MSM features
acoustically encoded (baddeley), capacity of 7+-2 (Miller) and duration of 18-30 seconds (Peterson and Peterson)
Process that keeps info in STM
Maintenance rehearsal (repeating information)
A lack of maintenance rehearsal of STM causes
forgetting/losing information
What causes information to pass from STM to LTM?
Prolonged maintenance rehearsal
LTM MSM features
semantically encoded, unlimited capacity, very long duration (bahrick et al)
How do we remember information?
Retrieval; information being transferred from LTM to STM
Evaluation of MSM (LTM types)
(limitation) Tulving proposed different types of LTM (procedural, semantic, and episodic). MSM sees LTM as a single unitary store and doesn’t separate types of LTM with separate retrieval processes - is a universal conscious retrieval in MSM.
Evaluation of MSM (maintenance rehearsal)
(limitation) Suggests amount of maintenance rehearsal determines likelihood of STM passing to LTM, but Craik and Watkins (1973) suggest type of rehearsal is more important (elaborative and making semantic links rather than prolonged repetition)
MSM evaluation (differences between LTM and STM)
strength) represents LTM and STM separately and acknowledges qualitative differences in encoding, duration and capacity. Portrays accurate view of differences between types of memory.
MSM evaluation (STM as unitary)
(limitation) Represents STM as single unitary store but Shallice and Warrington found amnesia patient KF had different STM recall for different stimuli types, suggesting multiple types of STM.
Components of WMM:
central executive, phonological loop, visuo-spatial sketchpad, episodic buffer
what is the role of the central executive
To allocate tasks to the three ‘slave systems’. Is an attentional process with limited processing capacity.
What is the role of the phonological loop?
processes auditory information. It is subdivided into the phonological store (which holds words we hear) and the articulatory process (which allows us to repeat words in a loop).
What is the role of the visuo-spatial sketchpad?
combines visual and spatial information processed by other stores to give us a ‘complete picture’.
What is the visuo-spatial sketchpad divided into?
Inner scribe and visual cache
Capacity of VSS
4-5 chunks
What is the role of the episodic buffer?
Integrates all types of data processed by other stores. Described as the storage component of central executive. Crucial for linking STM to LTM
What are the 3 types of LTM?
episodic, semantic, and procedural
What are episodic memories?
Those with personal meaning to us, with details about when and how the events occurred, and people and places (i.e. a wedding)
What are semantic memories?
Knowledge - understanding of words, concepts, and themes. helps us to sue information related to one concept to help us understand another
What are procedural memories?
Memories of learned skills like swimming or driving
Which types of LTM are recalled consciously and which are recalled unconsciously?
Episodic and semantic recalled consciously, procedural unconscious
Support for types of LTM (Petersen et al)
Demonstrated semantic memories and episodic memories were recalled from different sides of prefrontal cortex. Shows they each have different neurological basis as recalled from different parts of brain.
Support for types of LTM (practical application)
Belleville et all says mild cognitive impairments most commonly affect episodic memories, so increased understanding of these could lead to improved targeted treatments
Support for types of LTM (case studies)
HM and Clive Wearing show that one type of LTM may be impaired but others will be unaffected. Clive Wearing played piano and understood music very well but forgot episodic memories almost immediately. Supports the idea different areas of the brain are involved and types of LTM are separate.
What is interference?
Where recall of one memory blocks recall of another, causing forgetting or distortions.
What is retroactive interference?
Where new memories block the recall of old memories
What is proactive interference?
Where old memories block the recall of new memories
Who demonstrated retroactive interference? What was the procedure and findings?
McGeoch and McDonald (1931). Participants had to learn a list of 10 adjectives perfectly then go into groups to do different activities. Found that the group for whom the new activity was learning synonyms, they recalled 3 less of the original words than a control group which did no activity.
What does McGeoch and McDonald (1931) support
That the extent of forgetting is larger/more likely when the two memories are similar
What is a criticism of McGeoch and McDonald?
Artificial stimuli with no personal meaning has low mundane realism. In real life we learn meaningful lists linked to our lives/personal meaning (i.e. shopping by knowing what you like/ what cupboards are missing). Factors other than interference may therefore have a large influence on forgetting.
Support for interference theory (lab studies)
Consistently demonstrated in several lab studies, increasing validity due to highly-controlled conditions.
Support for interference theory (Baddely and Hitch)
Baddely and Hitch asked a group of rugby players to recall their last game and the number of games they’d played that season. They found the more games they’d played, the more retroactive interference they would experience as new memories blocked recall of older games.
Two factors affecting the accuracy of eyewitness testimony
Misleading information and anxiety
What is eyewitness testimony
The ability of people to remember the details of events, such as accidents and crimes, which they have observed
Why is misleading information and leading questions such a big problem for EWT?
Police and lawyers may try to direct a witness to give a misleading answer
What is the research on leading questions?
Loftus and Palmer (1974). Car crash clips - mean reported 40.5mph for smashed and 31.8mph for contacted. Smashed reported broken glass a week later (there was none.
What did the research on leading questions (L+P 1974) show?
That leading questions could bias witness recall of events.
What are the 2 explanations for why leading questions affect EWT?
Response-bias and substitution
