Memory Flashcards
What is the threefold process of remembering information?
registering/acquiring info - coding
retaining
retrieving
But what three sections of memory do we study?
Capacity, duration and coding
What is capacity?
how much our memory can hold
What is duration?
How long our memories can last
What is coding?
The way info is changed so it can be stored- e.g. acoustic or visual form
What is the capacity of the sensory register?
Very large
Who studied the capacity of the sensory register?
Spirling- Flashed a 3x4 grid to for 1/20th sec, pps asked to recall rows or entire grid.
Recall was high no matter which row- suggests all info was in the sensory register
What is the capacity of Short term memory?
7 +/- 2 items
Who studied the capacity of short term memory?
Jacobs: pps given strings of letters and no.s to remember, length of string increased until they couldn’t remember
Pps recalled approx. 9.3 no.s & 7.3 letters
What is chunking?
We divide strings of letters/ no.s into chunks to remember them more easily
What is the capacity of Long Term Memory?
unknown/extremely large
Who studied the capacity of LTM?
Wagenaar: created a diary of 2400 words over 6 years, excellent recall of all events
What is the duration of the sensory register?
approx. 500 milliseconds for iconic sensory store
limited duration/different rates of decay for different info
Who studied the duration of the sensory register?
Walsh and Thompson- found that the iconic sensory store is approx. 500 milliseconds
What is the duration of STM?
very short/ up to 30 seconds
Who studied the duration of STM?
Peterson and Peterson: pps shown a nonsense trigram, asked to count backwards in 3s from a 3 digit no. to prevent rehearsal, repeated for various intervals
80-90% letters recalled after 3secs, 10% after 18secs
Who studied the duration of LTM?
Bahrick et al: 400pps from a high school asked to name people in yearbook, (recall) 60% after 15yrs, recognition 90% after 15 yrs
What is the duration of LTM?
indefinite- very long/lifelong
What is the coding of the sensory register?
Separate stores for different senses; verbal info- stored acoustically, pictures/faces- stored visually
Who studied the coding of the sensory register?
it was found biologically (although Crowder did study it)
What is the coding of the STM?
coded acoustically- affected by acoustically similar information
What is the coding of the LTM?
coded semantically- affected by semantically similar info
Who studied the coding of LTM and STM?
Baddely: gave pps 4 sets of words: acoustically similar/dissimilar and similar in meaning/not similar in meaning. pps had to recall immediately or after 20mins
found LTM- semantic and STM- acoustic
Who created the multi store memory model?
Atkinson and Shiffrin
Why is the multistore memory model important?
1st model to suggest multiple stores
How can the multistore memory model be described?
How is info stored/lost according to model?
info from senses flows into SR (here can decay quickly), if attention paid flows into STM (here can be displaced or decay) info can be kept here or sent to LTM by maintenance rehearsal. In LTM can be lost by interference/retrieval failure/decay
How can the multistore memory model be described?
How can info be retrieved?
info can be retrieved from the STM,
to retrieve info from LTM it flows from LTM into STM to be retrieved
What are the strengths of the MSM?
1st model to suggest different stores, research support: duration- Peterson+Peterson, coding- Baddely, capacity- Jacobs. Glanzer and Cunitz
What are the weaknesses of the MSM?
there is more than one STM- Shallice and Warrington
There is more than one LTM- Clive Wearing
Different ways of getting LTM- flashbulb memory
What did Glanzer and Cunitz study?
Found Primary and recency effect
pps remembered words at the beginning and end of lists
What is the primary and recency effect?
Primary effect: first words are remembered as they’re rehearsed so go into LTM
Recency effect: last words stay in STM so are remembered
What did Shallice and Warrington study?
Studied KF- he had amnesia after motorbike accident which caused brain trauma- His STM was damaged
Couldn’t remember info read out loud to him but was able to read info and remember it
Suggests multiple STM stores for visual and verbal info
What is the case of Clive Wearing?
Was a world class musician; virus caused brain damage; damaged LTM and stopped him moving STMs to LTM Still has procedural memory (play piano) but can't remember children's names (semantic memory) or wedding day (episodic memory)
What does Clive Wearing’s case suggest?
That there are multiple LTM stores (for procedural, semantic a episodic memory)
What is flashbulb memory?
Info goes straight into LTM (can be due to heightened emotion, but can be unexplained)
What is a criticism of maintenance rehearsal?
Some things we can repeat a lot but do not make it into the LTM
What is semantic memory?
Knowledge about the world/facts. Not time stamped. Are declarative (you can use conscious effort to recall these memories).
What parts of the brain are involved with semantic memory?
Hippocampus, Temporal lobe
What is episodic memory?
They are complex and have three key components; the event, the emotion, the time it happened
They are time stamped and declarative
What parts of the brain are involved with episodic memory?
Prefrontal cortex, Temporal lobe
What is procedural memory?
Memories of actions or skills
Take longer to learn, learnt through repetition, they are not declarative. They are not thought to be time stamped
What parts of the brain are involved in procedural memory?
Basal ganglia, cerebellum
What is a weakness of the current long term memory division?
Priming: seems to be controlled by the brain stem, therefore separate from other LTM stores. Perpetual representation system which helps prime memories
Who came up with the working memory model?
Baddely and Hitch- felt STM must have separate verbal and visual stores. Proposed that the STM had multiple stores, it emphasises active processing
What are the components of STM in the WMM?
Central executive, ‘Slave systems’: Visuo-spatial sketch pad and phonological loop, Eposodic buffer (added in 2000)
What does the central executive do?
monitors incoming info, has limited capacity, plays a critical role in attention and delegates tasks to the ‘slave systems’
What does the visuo-spatial sketch pad do?
processes visual and special info
What is visual and spatial information?
visual info- anything seen as a picture
spatial info- estimate the spaces between objects
How is the visuo-spatial sketch pad divided?
Visual cache: stores visual data (form and colour)
Inner scribe: records arrangement of objects in the visual field
What does the phonological loop do?
Deals with acoustic info (anything with words- even if words are seen not heard), limited capacity
How is the phonological loop divided?
Phonological store: holds what you hear
Articulatory process: allows for maintenance rehearsal (sub vocal repetition)
What is the episodic buffer?
integrates visual, spatial and verbal info into a single memory
Why was the episodic buffer added to the WMM?
All the other parts of the model have limited capacity, so there was no where for holding info, which led to the addition of the episodic buffer as a temporary general store
What are the strengths of the WMM?
Biological evidence for multiple stores- Bunge et al, case study KF, Baddely et al
What are the weaknesses of the WMM?
central executive too vague, more than one central executive
What did Baddeley et al do? (WMM)
condition 1: 2 tasks requiring visuo-spatial sketch pad
condition 2: 2 tasks requiring different stores (V and P)
pps could do tasks easily for different stores but not for same store
Why is the Central Executive too vague?
Despite being the most important component of the model the CE has little info- exact role is unclear
What suggests there might be more than one central executive?
Study of EVR- he performs well on tests requiring reasoning but poor at decision making- suggests that the CE has multiple stores/sections, diagram is too simplistic
What is retrieval failure?
A form of forgetting where we do not have the cues we need to access a memory.
Why do we need cues to access a memory?
When we code something into our memory, cues are stored at the same time. If the same cues are not present when we want that info, it may appear that you have forgotten it- when it simply isn’t accessible
What is a cue?
A trigger to something (e.g. a trigger to info that accesses a memory)
What is the coding specificity principle?
Found by Tulving: For a cue to help us recall info, it must be present when the info was coded AND when we recall the info
What are the two types of retrieval failure?
Context dependent forgetting, state dependent fogetting
What is context dependent forgetting?
Occurs when external retrieval cues at coding and recall do not match- (e.g. forgetting something in one room because you learnt it in another)
Godden and Baddeley
What is state dependent forgetting?
Occurs when internal retrieval cues at coding and recall do not match (e.g. forgetting info when sober because you learnt it when drunk) Carter and Cassidy
What did Godden and Baddeley do?
Wanted to see if context affected recall: divers learnt list of words either under water or on land and recalled it on land or under water in 4 different conditions.
supported idea of context dependent forgetting
What did Carter and Cassidy do?
Changed internal state of pps to see its effects on recall
used anti-histamine drugs- mild sedative effect
recalled/learnt either on or off drug in 4 different conditions. supported idea of state dependent forgetting
What are the strengths of the retrieval failure theory?
research support, real life applications
What are the weaknesses of the retrieval failure theory?
Context effect may be different depending on type of recall, context isn’t that mportant
How can the retrieval failure theory have real life applications?
When we are remembering something going back into situation may help us recall it- key idea in cognitive interview for Eye witness testimony
How can context effect vary depending on the type of recall?
Godden and Baddely recreated diver experiment using recognition test instead of recall. No context dependent effect with recognition
Why might it be considered that context isn’t that important in memory retrieval?
Some argue that the context effect isn’t that strong in real life - contexts have to be very different for this effect to be seen
What are the two types of interference?
Proactive interference and retroactive interference
What is interference?
Forgetting because one memory interferes or blocks another memory, causing one or both memories to be distorted or forgotten
We are more likely to forget if the memories are more similar
What is proactive interference?
forgetting occurs when OLDER memories DISRUPT recall of NEWER memories
What is retroactive interference?
Forgetting occurs when NEWER memories DISRUPT recall of OLDER memories
Who studied proactive interference?
Underwood- analysed multiple studies- found that when pps have to learn a series of word lists they don’t remember the later lists as well as the earlier lists
if pps remembered 10+ lists after 24hrs they remembered only 20% if only learned 1 list recall= 70%
Who studied retroactive interference?
McGeoch and McDonald: pps had to learn word list until 100% accuracy, then learned 1/6 types of list (same/different meaning, unrelated, nonsense syllables, numbers and no list) pps then recalled
What did McGeoch and McDonald find?
results depended on 2nd list type- same meaning= worst recall (followed by opposite meaning, whereas no list=best recall)
What are the strengths of interference?
Real world applications, strong evidence from lab studies, support from real life studies
What are the weaknesses of interference?
Artificial tasks used in research, overcoming interference with cues
What are the real world applications of interference?
Danaher et al found both recall and recognition of an advert were impaired when pps were exposed to adverts for another brand within a week
Why is the artificial tasks of lab studies a weakness of interference?
Word lists are different from the types of information we learn day to day, pps also lacked motivation to learn and recall words as they have no personal meaning
so interference may not be as likely a reason for forgetting in real life
What support is there from real life studies for interference?
Baddeley and Hitch- asked Rugby players to recall teams they’d played with over the season. Results showed accurate recall didn’t depend on how long ago but on how many games had been played since
How can interference be overcome with cues?
Tulving and Psotka: gave pps lists of 24 words each list sorted into categories. Recall = 70% for 1st word list but fell as pps given more lists- presumably interference
But when given the titles of each list, recall rose again to 70%
What is eyewitness testimony?
The ability of people to remember the details of events such as accidents and crimes, which they themselves observed
What did the Devlin report find?
Found 850 cases where only evidence was EWT, 75% of these cases found guilty by a jury. Devlin committee advised not to base all of the case on EWT
What did Wells et al find in relation to EWT?
DNA testing in USA introduced in 1990- they reanalysed evidence. 40 people found to be wrongly accused- some even sentenced to death. In 36% if these cases, EWT was the major evidence against them
What did Marshall et al find in relation to EWT?
Found that air force personnel (who knew in advance they would be asked about the speed of a car) gave answers ranging from 10-5-mph. Actual speed 12mph. Suggests that EWT aren’t necessarily reliable
What did Loftus and Palmer research in relation to EWT
(smaller experiment)?
45 uni student pps: shown 7 video clips of car crashes, pps wrote recall of clip, asked to estimate speed of car, (5 conditions, 9pps in each) verb used changed in each condition; contacted, hit, bumped, collided or smashed
As verb intensity increased so did speed estimate
What else did Loftus and Palmer find in relation to EWT - (larger experiment)?
120 student pps: viewed car crash clip, 50 asked key question with ‘smashed’, 50 ‘hit’, 50 not asked at all.
When asked about recall of broken glass a week later (there wasn’t any) pps x2 as likely in smashed condition to falsely recall broken glass
What are the key factors that can affect EWT?
Leading questions, Post-event discussion, response-bias explanation, substitution explanation, anxiety
How can post event discussion affect EWT?
occurs when more than 1 eyewitness + they discuss events- this may influence recall accuracy
What is the response bias explanation for EWT?
Suggests that wording of question does not alter memory of event but influences the pps answer (e.g. smashed encourages pp to chose the higher end of their initial speed estimate)
What is the substitution explanation for EWT?
Wording substitutes itself for the actual memory- memories are altered. (e.g. memory of smashed glass in 2nd Loftus and Palmer experiment)
What did Bunge et al study?
biological evidence for more than one store- support WMM: used brain scans + found different parts of brain active when verbal (temporal l.) or visual (occipital l.) tasks done. under dual task conditions - central executive- the part of the brain involved in decision making + planning active (PFC)
