Memory Flashcards
the multi-store model of memory
what is coding?
the process of converting information between different forms
the multi-store model of memory
what was the research on coding?
baddley- gave diff lists of words to four groups of participants to remember
1. acoustically similar words
2. acoustically dismiliar words
3. semantically similar words
4. semanticaly disimilar words
* they were shown original words and asked to recall them in correct order
* when done immediately ( recalling from stm)- they did worse with aucoustically similar words
* when recalled after a time interval ( recalling from ltm)- they did worse with semantically similar words
the multi-store model of memory
how is information coded in the STM and LTM?
acoustically= STM
semantically= LTM
the multi-store model of memory
what is capacity?
how much info can be held
the multi-store model of memory
what is digit span- research on capacity?
Jacobs- found out the capacity of the stm by measuring digit span
* e.g research reads out four digits and the participants were asked to recall these out loud in correct order
* if that is correct the research then reads out 5 digits and carries on adding on until particiipant cannot recall the correct order
* this indicates digit span
the multi-store model of memory
what was the mean digit found?
9.3 items for digits and 7.3 for letters
the multi-store model of memory
what was chunking- research into capacity?
Miller- used this to measure the capacity of STM= 7 items plus 2 or minus 2
* also noted that ppl can recall five words as easily as they can recall five letters- done by grouping sets of digits or letters into units or chunks
the multi-store model of memory
what was the research on the duration of the STM?
peterson and perterson
* tetsed 24 students in 8 trials
* each trial student was given a consonant syllable e.g (ycg) to rememeber + also given a 3 digit number
* student counted backwards from this numbver until told to stop- to prevent mental rehersal of ycg (swould increase duration)
* on each trial they were told to stop after varing periods of time 3,6,9,12, 15 or 18 secs
the multi-store model of memory
what were the findings from the duration research by peterson and peterson?
- after 3 seconds- average recall was about 80%
- after 18 seconds it was about 3%
- findings suggest that STM duration must be around 18 seconds unless verbal/mental rehersal happens
the multi-store model of memory
what was research on the duration of LTM?
Bahrick et al
* 392 american 17-74 aged participants
* used highschool yearbooks to test this 1 photo-recognition 2- free recall ( of names in graduating class)
* when tested within 15 years participants were 90% accurate with photo task after 48 years recall dropped to about 70%
* name task was less accurate 15 years= aout 60% 48 years= 30%
the multi-store model of memory
what did the duration research show?
LTM duration can last up to a lifetime
how does the the multi-store model of memory work?
sensory register —-> STM—> LTM
what is the sensory register?
stimuli from environment pass into it
* has the senses in it see,hear,taste etc
* coding- depends on the sense e.g coding for visual info is ionic and for sound is echoic
* duration- less than half a second
* capacity- very high
* info only pass through into STM only if you pay attention to it
cdc
what is the STM?
coding- acoustic
duration- limited 7+-2
capacity- 18 unless rehersered
cdc
what is the LTM?
Coding- semantic
duration- unlimited
capacity- up to a lifetime
what is the case of HM?
- underwent surgery for epilepsy
- his hippocampus was removed- important for memory function
- when his memory was assesed in 1955 he thought it was 1953- he had very little recall of the operation
- he could not form new long term memories
- despite all this he performed well on tests of immediate memory span ( stm measure)
tulving
what are the three different types of LTM?
episodic
semantic
procedural
what is epidosic memory?
ability to recall events from our lives
1. the memory is time-stamped when and what happened
2. memeory of a single episode includes several elements e.g ppl places etc, all of this is combined to create a single memory
3. have to make concious effort to recall episodic memories
what is semantic memory?
shared knowledge of the word knowledge of things meanings of words
knowledge of concepts e.g love
these are not time stamped as we usually dont remember when we first heard about something new
constantlly added to and is less vulnerable to disortion
what is procedural memory?
our memory for actions and skills/ how we do things
we can recall these without concious awareness or much effort- it becomes automatic through practice like driving
might find it difficult to explain to someone else
baddley and hitch
what is the working memory model?
how aspects of STM are organised and their fucntions
its concerned with the mental space that is active when we are temporarily storingring and manipulating info
4 main components
WMM
what is the central executive?
- monitors incoming data, focuses and divides our limited attention and allocates subsystems like phonological loop to tasks
- has very limited processing capacity and does not store info
WMM
what is the phonological loop?
deals with auditory info ( coded acoustic) and is temporary
subdivided into:
* phonological store- words that you can hear
* articulatory process- allows maintence rehersal
capacity is 2 seconds worth of what you can say
WMM
what is the visuo-spatial sketchpad?
stores visual and/or spatial info when required
has limited capacity ( about 3-4 objects)
subdivided into:
* visual cache- stores visual data
* inner scribe- records the arrangement of objects in visual field
WMM
what is the episodic buffer?
added by baddley in 2000
* temporary store for info, intergrating visual, spatial and verbal info processed by the other stores and maintaining a sense of time sequencing
* can be seen as the storage component of central executive
limited capacity of about 4 chunks
* links working memory to LTM and wider cognitive processes e.g perception
what is the interference theory of forgetting?
forgetting takes place because of interference- when two pieces of info disrupt eachother = forgetting one or both
mainly for LTM
what is proactive interference?
when an older memory interferes with a newer one
what is retroactive interference?
when a newer memory interferes with an older one
McGeoch and McDonald
what was the research on effects of similarity for proactive and retroactive interference?
- studied retroactive interference by changing the amount of simialrity between two sets of material
- participants had to learn list of 10 words until they could rememeber with 100% accuracy
- then learned new list then put into 6 groups to learn diff types
McGeoch and McDonald- interfernce
what were the six groups?
- synonyms
- antonyms
- words related to original ones
- constonant syllables
- three digit numbers
- no new list ( control)
McGeoch and McDonald- interference
what were the findings?
when particpants were asked to recall original list of words, most similar produced worst recall shows that interfernce is strongest when memories are similar
McGeoch and McDonald- interference
what was the expalnation given for the findings of effects of similarity?
similarity affects recal because
1. previously storted info makes new similar info more difficult to store (PI)
2. new info overides previous similar memories because of the similarity (RI)
explanations for forgetting
what is retrival failure?
being unable to access memories that are there due to insufficent cues
when info is placed into our memory associated cues are also stored at same time but when these cues are not there at the time of recall it seems like we have forgotten
explanations of forgetting- retrival failure
what is the encoding speficifty principle?
if a cue is going to be useful it has to be both
1. present at learning (encoding)
2. present at retival (recall)
two examples of non-meaningful cues include
* context-dependent forgetting- recall depends on external cue
* state-dependent forgetting- recall depends on internal cues
explanations of forgetting- retrival failure-godden and baddley
what was the research into context dependent forgetting?
- deep- sea divers had to learnt list of words either under water or on land then recall the list underwater or on land
- four conditions in total- learn on land recall on land, learn on land recall uw, learn uw recall uw, learn uw recall on land
- found- accurate recall was 40% lower when conditions did not match e.g learn uw recall on l
- concluded that external cues available at learning were diffrenet to recall= retrival failure
explanations of forgetting- retrival failure - carter and cassaday-
what was research into state-dependent forgetting?
- gave antihistamines ( mild sedative effect) to participants making them slightly drowsy - creates a psychological state diff to normal state
- they then had to learn a list of words then recall the informtation
- resulted in four diff conditions- learn on drug recall on drug, learn on drug recall not on drug, lean not on drug, recall on drug and learn not on drug recall not on drug
- found- when the conditions were mix match performance was significantly worse- so when cues are absent there is more forgetting
factors affecting eyewitness testimony- misleading questions- loftus and palmer
what was the research on leading questions?
- 45 particpants ( students) watch film clips of a car accidents and then asked them questions
- in the critical question the particpants were asked how fast the cars were travelling
- five groups of participants and each given a different verb- hit, contacted, bumped, colided and smashed
- found- contacted- mean estimated speed was 31.8mph but with smashed 40.5 mph- the leading question biased ewt
factors affecting eyewitness testimony- misleading questions
why do leading questions affect ewt?
- the response-bias explanation- wording of question has NO a real effect on memory but just influences it
-
substitution explanation- wording of the leading question ALTERS memory of what happened
* other experiment participants who heard smashed then said they remember seeing glass (the critical verb altered the memory of incident)
factors affecting eyewitness testimony- misleading questions- gabbert et al
what was the research on post event discussion?
- 120 participants watched a video of a girl stealing money
- tested in pairs ( co-witness group) or individually (control)
- p’s in co-witness told that they had watched the same video but actually saw different perspectives of the same crime and only one person actually witnessed girl stealing
- participants in co-witness group discussed together then all participants completetd a questionare
- found- 71% of the witnesses in co-witness group recalled info they had not actually seen and 60% said that the girl was guilty despite not seeing her commit the crime- highlights issue of post event discussions powerful effect
factors affecting eyewitness testimony- misleading questions
why does post event discussion affect ewt?
- source monitoring theory memeories of the event are genuinely distorted, person can recall info about the event but cant recall where it came from
- conformity theory- eye witnesses recall appears to change only bc they go along with the account of co-witness
factors affecting eyewitness testimony- anxiety
what are the effects of anxiety?
- has strong emotional and physical effects- but not clear if these make ewt recall better or worse research supports both
factors affecting eyewitness testimony- anxiety- johnson and scott
what was the research of anxiety have a negative effect on recall?
- anxiety creates physiological arousal preventing us from paying attention to important cues= worse recall
- participant’s either in:
- low anxiety conditon heard a casual convo in next room then saw a man walking past with greasy hands holding a pen
- high anxiety condition particpants heard a heated argument, sound of breaking glass following a man walking out holding a knife covered in blood
- particpants later picked out man from 50 pics
- 49% who saw man with pen were able to idnetify him but 33% particiapnts who saw knife were able
- shows that people have enhanced memory for centeral events- wepon focus as a result of anxiety can have this effect
factors affecting eyewitness testimony- anxiety-yuile and cutshall
what was the research for anxiety having a positive effect on recall?
- fight or flight response increases alertness so this can make ppl become more aware of cues in a situation
-
study of real shooting in a gunsop in Canada- shop owner and theif = dead
13/21 witnesses took part in study - were interviewed 4-5 months after the incident and these interviews were compared with the police interviews at the time of the actual shooting
- acuaracy was determined by the number of details recorded in each account
- also asked to rate how stressed they were at the time of the incident and wheter they had any emotional problems since the incident
factors affecting eyewitness testimony- anxiety
what were the findings from the anxiety positive effect study?
- witnesses were very accurate in their accounts and there was little changes in the amount recalled or accuracy after 5 months- but some details were less accurate e.g colour of items
- partcipants who reported highers stress levels were most accuarate
- suggets that anxiety doesn’t have a negative effect on accuracy and can actually enhance it
factors affecting eyewitness testimony- anxiety-yerkes and dodson
what are the basics to the anxiety contradictory effects explanation?
- the relationship between emotional arousal and performance is an inverted u
- psych reviewed 21 studies of ewt using the inverted u theory to explain findings
- witness a crime/ accident = we become emotionally and physiologically aroused (anxiety + flight or fight response)
improving the accuracy of ewt
what are cognitive interviews?
a questioning technique used by the police to enhance reterival of info about crimes from the eyewitness and victims memory
improving the accuracy of ewt
what are the four main techniques used for the cognitive interview?
- report everything- witnesses encouraged to include every single detail could trigger other important memories
- reinstate context- interviewer tries to mentally reinsate the environmental and personal context of the crime for the witness, asked to use all 5 senses to help- can trigger context dependent memories
- reverse the order- recounting the incident in a diff narrative order, to prevent witness reporting their expectations for how the vent must have turned out + prevents dishonesty
- change perspectives- report it from a diff perspective, describing what they think of other witnesses may have seen- this disrupts the effect of expectations and schema on recall
cognitive interview- enhanced cognitive interview
what elements were later added on by fisher to improve ci?
- minimise distractions
- reduce ewt anxiety
- guidance on when to maintain eye contact and when to withdraw it
- get witness to speak slowly
- ask open-ended questions
factors affecting eyewitness testimony- anxiety-yerkes and dodson
what is the link between recall accuracy and level of anxiety?
explanation for contradictory findings
lower levels of anxiety/arousal- produce lower levels of recall accuracy- memory becomes more accuarte as the level of anxiety increases
* HOWEVER - there is an optimal level of anxiety which is the point of MAX accuarcy
* if a person experiences anymore arousal then recall significantly declines
multi-store model of memory- atkinson and shiffirn
what does it do?
it describes how info flows through them memory system
memory is made up of three stores linked by processing
