topic 2: memory Flashcards
what is memory
its learning that has persisted over time, it’s our ability to store and retrieve information
how would you test the duration of short term memory
- give participants something to remember that has no meaning and can’t be remembered as a whole, eg. random trigram not a word or acronym
- distract them so that they can’t repeat it
- ask them to recall after different durations (5,15,15… 30 seconds etc.)
what was the study done on duration of STM
Peterson+Peterson
they investigated the duration of short term memory
laboratory experiment with a 24 psychology student sample
- had to recall meaningless three letter trigrams at different intervals
- had to count back in 3s or 4s from a specific number to prevent repetition
decided STM was 18-30 seconds
extrapolated their data to find that STM recall after 30 seconds would be 0
evaluate the Peterson & Peterson STM duration study
they investigated the duration of short term memory
+ standardised procedures made it repeatable
eg. use the same trigrams
– low ecological validity
we don’t usually count backwards in 3s to prevent repetition, so our STM isn’t actually used in the way that the study says it is
– low validity
the trigrams are meaningless, IRL we remember meaningful info.
participants could instead be told to write a shopping list then shop without it
– can’t generalise
psych students were used - good at remembering info + prior knowledge could cause demand characteristics
what study was done into STM capacity
the Jacobs study
participants were given lists of words/numbers
they had to immediately recall what was written in order after it was taken away
Jacobs gradually increased the length of the letters/digits until only on 50% of occasions could the participant recall correctly
he discovered number recall was easier than letters
people recalled an average of 9.3 numbers and 7.3 letters
he concluded that STM capacity was between 5 and 9 items
as age increases we appear to develop better recall strategies
evaluate the jacobs study on STM capacity
it was about the capacity of short term memory
– the research is old (1887), there may have been a lack of standardised scientific method
so extraneous variables may not have been controlled the room could be noisy/difficult word list
– repeated measures design increases chance of order effects
– low ecological validity
we usually remember things that are meaningful, not random letters or numbers; they have no incentive to remember these things
eg. remembering a number plate after a car crash
+ it provided useful knowledge surrounding capacity; eg. phone numbers and etc. are a length that can be remembered
+ a simple, standardised procedure that can be repeated
what can increase the capacity of STM
chunking; grouping together similar words/topics
define encoding
when information comes into our memory system from sensory input, it has to be changed into a form that the system can cope with in order to be stored
What study was done to explore encoding in STM and LTM
Baddeley
there were four groups; acoustically similar/acoustically dissimilar/semantically similar/semantically dissimilar
p’s were given a list with the og words in the wrong order and had to rearrange (either immediately/after 20 minutes)
DV was score on 10 word recall test
20% less of acoustically dissimilar were recalled than acoustically similar
so, STM must store acoustically since they got confused with similar sounding words
after 20 mins; list 4 recalled better than list 3, so LTM encodes semantically as they got confused with similar meanings
evaluate Baddeley’s study on LTM/STM encoding
+ repeatable; standardised procedures
4 conditions, 10 words, test 5 times, immediately + after 20 minutes
— ecological validity
meaningless words recalled, but in real life info has meaning and significance
+has been useful in day to day life
LTM encodes semantically, so it makes more sense to revise with mind maps vs reading out notes
describe the study on vLTM
Bahrick et al
almost 400 p’ between 17 and 74 were tested on memory of school friends
had to: free recall of classmates names
photo recognition test
name recognition test
photo matching test
year books were used to check for accuracy
p’s that had left school up to 34 yrs ago had a 90% accuracy on recognition tasks, for 48 years ago it was still 80%
evaluate Bahrick’s study on vLTM
+ repeatable if you have year books; so can be tested on different populations to find consistent results
+— ecological validity
mainly photograph recognition task - due to the meaningful stimuli
BUT matching photos and names has low ecological validity
— extraneous variables lower validity
may have seen classmates online/mentioned/in contact
+ protection from harm
researchers went to homes of elderly to interview incase they were distressed bc of not remembering names
what are the two models for memory
the multi store model of memory
the working memory model
what are elements of the multi store model of memory by Atkinson and Shiffrin, 1968 and how do they work together
information moves through the model in a linear manner and each store is viewed as separate and passive
what did HM and the star in the mirror task show
the task involved having to outline a star while looking at it in a mirror; a task that naturally requires practice
Henry had no recollection of previously completing the task but still improved each time
this was due to him being able to update his Procedural memory not his declarative memory
declaritive memory
a type of long-term memory that involves conscious recollection of particular facts and events.
procedural memory
cerebellum
Procedural memory is a part of the implicit long-term memory responsible for knowing how to do things.
what are some positives the multi-store model of memory
+ It’s supported by HM - it showed that LTM and STM are separate because it showed that the loops are different;couldnt form new LTM but could retrieve old LTM using STM
+ Peterson found STM duration to be 18-30 seconds vs Bahrick found LTM to be much longer - after 48yrs 80% of p’s still remembered their classmates
the durations are different so they must be separate, BUT they’re both lab research so have low ecological validity
+ MSM acknowledges qualitative differences between LTM and STM
bc it has separate stores for each
represents how eg. STM is encoded acoustically vs LTM is encoded semantically (supported by Baddeley and Miller)
what are some negatives of the multi store memory model
– it doesn’t consider the different LTM stores
it sees LTM as a single, unitary store, it doesn’t consider procedural, semantic and episodic LTM
also doesn’t represent how info can be transferred unconsciously to STM
– doesn’t consider the different aspects of STM as shown by KF
outline the sensory register
duration - short
capacity - very large
encoding - modality specific
we have no cognitive control over it
outline the STM store
duration - 18-30 seconds
capacity - 7 plus/minus 2, can be increased via chunking
encoding - acoustically
what does maintenance rehearsal do
it is when information is repeated continuously, the information will stay in STM
what is elaborative rehearsal
when the info is processed in a meaningful way that links it with info already in LTM to move it into LTM
outline the LTM store
duration - very long, may be unlimited, over 46 years (Bahrick et al.)
capacity - unlimited
encoding - semantically
outline the case of HM, Henry Molaison
he had severe epilepsy (around 10 seizures daily) due to a fall as a child
it was known that partially removing the hippocampus could decrease seizures, as medication wasn’t working, his dr wanted to remove the whole hippocampus
post surgery he seemed normal but he couldn’t remember meeting his new dr and reintroduced himself each time; he’d lost his STM (and had anterograde amnesia)and couldn’t form new declaritive memories
BUT, he could eat and communicate, his old memories were unaffected, he could do maintenance recall
outline the working memory model
describe the central executive (WMM)
limited capacity - 4 items
it can process info from any of the sensory systems
it allocates tasks to the sub-systems
components can only communicate with each other via the CE
outline the visuo-spatial sketchpad (WMM)
it is a divided system
the passive visual cache stores info about how things look (form, shape, colour etc.)
the active inner scribe works with spatial information of objects in 3D space
capacity is around 3-4 objects
outline the phonological loop (WMM)
it’s made of the articulatory control system and the phonological store
phonological store processes auditory information and allows for maintenance rehearsal - it can hold spoken word for 2 seconds
articulatory control system has a sub vocal rehearsal mechanism
describe procedural memory
cerebellum and motor cortex
it’s implicit long term memory
it is the memory used for actions and learned skills (muscle memory)
recall occurs without effort/awareness
many of these memories are formed in early life e.g. walking
describe semantic memory
temporal lobe
declarative (explicit) long term memory
it isn’t time stamped or very personal
it’s our memories of our world and the associated knowledge
a conscious effort is needed to recall them
the memories are taught
what are the types of LTM
procedural
semantic
episodic
describe episodic memory
hippocampus
it’s declarative (explicit) long term memory
it is memory for events, and therefore time stamped and very personal
a conscious effort is needed for recall
they are not taught
outline the episodic buffer (WMM)
it integrates information from STM and LTM
it’s a general storage facility for info from all systems and LTM
info from all the subsystems is formed together to create a single memory that includes visual, spatial and auditory info
it maintains a time sequence by essentially recording events (episodes) that happen
it was added to help explain what the CE couldn’t
positives and negatives of the working memory model
+ it has made important contributions to memory research
psychologists could explain research that didn’t fit with MSM
ev: KF damaged some STM after an accident (struggled with verbal but visual was fine)
conc: STM has seperate parts, our understanding of memory has improved massively and the knowledge can be used to aid learning
+ prabhakaran; fMRI brain scans
2 tasks with equal visual and spatial info were used
1. had info separated, 2. had info integrated
they each used different parts of the brain, proving the existence of the episodic buffer
+ dual task performance studies support the existence of a visuo-spatial sketchpad
ev: Baddeley et al. found that p’s found it harder to do 2 visual tasks than one visual and one spatial simultaneously
conc: a higher ability of visual + spatial suggests that there is a separate subsystem that processes each input, the visuo-spatial sketchpad
– inferences have to be made as the structures are not visible, these inferences may be wrong
define forgetting
the inability to remember
what is interference
when 2 pieces of information are in conflict with each other
what is proactive interference
older memories disrupt new memories
eg. a teacher mixing names of a past class so she can’t remember names of a new class
what is retroactive interference
when new memories disrupt the older ones
eg. learning french then italian, but italian slips out when you speak french
outline the 2 theories for interference theory
- competition of response theory
information isn’t lost, the wrong info in the memory is just being accessed, new info can shift old memory - unlearning theory
old learning is actually replaced by new learning
evaluate the interference theory
+ lab experiments give evidence support
Tulving and Psotka gave p’s either 2 or 6 lists of 24 words, they had to free recall words they could remember; 2 lists was more accurate than 6
this is an example of retroactive interference
+ Baddeley + Hitch, rugby players who had played every game were more likely to forget matches: the later games had interfered with a recall of the earlier matches i.e. retroactive interference
— the studies are artificial and lack mundane realism
participants had to recall words around an hour after learning which doesn’t reflect how much time we have between learning and recall IRL, usually months/weeks or at least days
— interference isn’t the only explanation for forgetting
Tulving + Psotka then gave category names to the participants which acted as cues and p’s recalled around 70% of given words. so interference must just mask what is available, the info is still there but harder to retrieve, considering only interference would be over simplistic
what are the two explanations of forgetting
interference and retrieval failure
what is a cue
a trigger of information that allows us to access a memory
what kind of things could be a cue
they can be meaningful or linked indirectly by being encoded at the time of learning
tulving said that cues help recall if the same ones are present at both learning and retrieval
they can be
context, state or organisational
what could a lack of cues result in?
retrieval failure; when info is initially placed in memory, associated cues are also stored so if cues aren’t available at recall, the memories there may also be inaccessible
what is the Encoding Specificity Principle
it states that memory improves when info available at encoding is there at retrieval also, the retrieval cue will work better the more similar it is to the original cue
what is context-dependent forgetting and what study shows it
when memory retrieval is dependent on an external cue, but the external cue at recall doesn’t match that at encoding
Godden + Baddeley (1975); there were 4 conditions, landland, landwater, waterwater, waterland (1st is learn, 2nd is recall) recall was found to be significantly better with matching conditions
what is state dependent forgetting and what study supports it?
when memory retrieval is dependent on an internal cue (state of mind, stress); info is forgotten if internal cues at encoding don’t match those present at recall
Goodwin et al (1969); p’s were told to hide £$ and alcohol when drunk then find when drunk vs sober, it was found more when in same state than a different state
evaluate retrieval failure
+ context cues have useful applications for police
police use cues to their advantage in cognitive interviews. different senses which act as cues to discover more of what happened. this is good because memory research is £££, and the world is actually benefitting from it
— context effects aren’t actually that strong
Godden+Baddeley study lacks ecological validity as they chose Very different env,. (water+land), but env. aren’t actually that different at learning vs recall so it’s not an accurate depiction
— there are other theories that explain forgetting
eg. rugby players study shows retroactive
interference
+ we have everyday examples of cue dependent forgetting
eg. remembering something after hearing the first letter
outline Loftus & Palmer’s experiments and findings
aim: does the phrasing of a question influence judgement of speed to test accuracy of EWT and leading questions
exp 1: independent measures design; 5 groups of 9 = 45 students
criticial q- abput how fast where they going when they ** each other
**= smashed, contacted, bumped, hit, collided
DV= speed estimate
7 traffic accident films were shown; p’s had to 1. free recall the incident 2. do a questionnaire
approx. smashed was 10mph higher
conc- question form can affect accuracy of answers from an eyewitness significantly
conducted a 2nd, similar exp to get more evidence
exp 2: 3 groups of 50 students watched 1 film of an accident
the verb used to describe the accidents: smashed/hit/control (no comment)
DV- estimated speed, recollection of broken glass
participants returned a week later so they wouldn’t remember what verb was used
critical q; did you see any broken glass?
there was no broken glass but % yes was Smashed - 32%, hit + control - approx 15%
conc; the memory of car crash and memory of the verb became 1 memory, so leading questions reduce the reliability of EWT
what are two explanations for the consequences of using a leading question
- response bias explanation: words in q don’t actually change the memory, just the short term response
- alternative explanation: the wording changes the original memory
evaluate the Loftus and Palmer study
– research is artificial, lacks ecological validity
p’s were shown either 7 or 1 film(s) of an accident; it’s a clip so they will feel more distanced from it than if they were there; they may be more susceptible to believing the verb used
+ standardized procedures
e.g. same room, same video clip, free recall then questionnaire with critical question
you can then replicate the experiment with different populations across different times to see if there is the same result
– results aren’t generalisable
both exps samples used students; they may not drive/ haven’t been doing it for long and not understand what cars at like at speeds
being unsure ould make them more easily influenced by the verb used
+ application of the research to the justice system
results showed leading questions altering memory; 32% of smashed vs 12% of control said yes to broken glass
this prevents the wrong people being in jail due to leading q’s
– individual differences
Rhodes found older people to be less accurate than younger people when giving eye witness reports
what is memory contamination
when co-witnesses discuss a crime and mix information from their own memories with memories of other witnesses
outline the study done on post event discussion
Gabbert et al
studied participants in pairs; 1 saw the crime with a book, 2 saw the same crime but with a red handbag
they discussed what they saw before completing a test : 71% reported something they didn’t see when asked ‘what did you see?’
control group had no discussion; 0% reported something they didn’t see
why? witnesses do this either for social approval or because they think other witnesses are right and they are wrong - memory conformity
evaluate memory conformity/contamination
– evidence of post event discussion altering EWT
Skagerberg and Wright showed p’s a dark brown haired mugger and a light brown haired one; p’s saw different clips and discussed after and then reported medium brown hair
+ IRL application
Gabberts study has led to police separating witnesses after a crime to prevent memory contamination
– low ecological validity
watching the crime on a clip is an artificial setting with no emotional impact where p’s would pay more attention than usual causing demand characteristics
+ reliability
the use of standardized procedure means that the research can be repeated and recreated
define anxiety
a state of emotional arousal where there is a feeling of apprehension and uncertainty brought on by a real, anticipated threat
a mental state of anxiety can impair both physical and psychological functioning
outline the study done on weapon focus
Johnson and Scott
field experiment
p’s sat outside a lab where they could hear people talking
a) amicable discussion about equipment failure, a man w/ greasy hands walks out holding a pen
b) hostile discussion followed by the sound of breaking glass and overturned furniture, a man w/ a knife and blood covered hands walks out
p’s were given 50 pics and asked to identify the man
(approx)
50% of peaceful identified
30% of violent identified
arousal curve thing
what is the tunnel theory of memory
it argues that witnesses’ attention narrows and focuses on a weapon because it is a source of anxiety, which is why they can describe a weapon in detail but not the rest of a crime scene
evaluate the effect of anxiety on EWT
+ there is real life evidence support
the horror labyrinth at the London dungeon; p’s wore hart monitors to record anxiety level and were then split into high vs low anxiety and had to describe an actor encounter in the labyrinth
high had more mistakes, 17% of high and 75% of low correctly identified the actor
– ethical issues; causes more stress than everyday life
Johnson and Scott research could be challenged for this; real life studies can be more beneficial as the’ve already witnessed a real life event and won’t need to create it
– real life crimes offer opposing evidence
Yuille and Cutshall; real life robbery where shop owner shot a gun thief dead
13 out of 21 witnesses agreed to participate in research
p’s were interviewed 5 months post incident, p’s reporting high stress were more accurate at 88% vs 75%
– the study may test surprise instead of anxiety
exp with scissors/handgun/wallet/raw chicken as hand held items in hairdressing salon video
EW was less accurate with chicken/handgun, aka high unusualness and also surprise factor
— violent crime victims were more accurate in EWT than non-violent crime victims so anxiety doesn’t uniformly affect EWT accuracy
what is a cognitive interview
a way of interviewing eyewitnesses about what they can recall from a crime scene or an event
It was developed as a way of improving EWT in order to enhance recall and thus lead to more accurate conviction of the perpetrator
break down a cognitive interview and the benefits
- free recall - the interviewer encourages the reporting of every single detail of the event, even though it may seem irrelevant
+ it avoids leading questions as you use your own words and aren’t influenced
+ this detail can also trigger other memories - recall from a changed perspective - recall from viewpoints of other people, how it would’ve appeared to them
+ it reduces the influence of schema - recall in reverse order - interviewers try to walk through the timeline of the incidents timeline alternatively
+ it reduces possibility of recall being influenced by schema/expectations
+ harder to lie backwards - context reinstatement - ask what did they see, feel etc. interviewee mentally reinstates the environmental context of the incident
+ cues may also trigger recall, based on the principle of retrieval failure/cue dependant forgetting
evaluate the cognitive interview
+ evidence support
Fisher et al. trained detectives in cognitive interview and they obtained approx 50% more information than before they were trained
it was a field study so high ecological validity, it shows the benefit when correctly applied
– time consuming
a rapport is established with the witnesses and they are given chance to relax, witnesses may also go into a lot of irrelevant detail because they are told to not leave anything out, they can’t really tell them to stop because to can interrupt the flow and they may miss a necessary detail
this makes it more expensive and less can be done and more salaries need to be payed etc.
+ we know that the report everything and context reinstatement stages work the best
this means that just these components can be used to make the interview shorter
useful to just save time but also when you want to minimise reliving trauma
– researchers found that although 81% more correct information was given, 61% more incorrect information was given
may be best to just use in the more intense cases
+ it’s good for encouraging elderly people to give info without reservation, they can be more hesitant because of negative conceptions about their memory
fisher used the interview on 22 vs 72 yr old males and saw more benefit with older group
what is the capacity of LTM
thought to be unlimited
there’s never been a case of someone being unable to learn new info
outline retrieval failure as an explanation for forgetting
a type of LTM forgetting that can be cue or state dependent and is where a memory cannot be accessed
what’s the capacity of the sensory store
unlimited
evaluate the types of LTM
+ brain scans give evidence because of their different locations
+ ⭐️ 🪞
+ evidence of different, seperate declarative stores
studied alzheimer’s patients that could episodic but not semantic whilst others found the opposite, so they can be formed independently
+ belleville studied how episodic memories can be improved in older people with a mild cognitive impairment, trained group did better in a test vs control!
what research looks at effect of anxiety on EWT
weapon focus (50% vs 33%) and yerkes-dodson
