memory Flashcards
what are the types of long term memory?
episodic
semantic
procedural
what is episodic memory?
time stamped events
explicit
strength of memory is linked to strength of emotion felt at the time
what is semantic memory?
knowledge
explicit
not time stamped, declarative
what is procedural memory?
performance of particular actions and skills
implicit
automatically retrieved
how is short term memory coded?
accoustically
how is long term memory coded?
semantically
who researched coding?
Baddeley (1966)
what was Baddeley’s method?
he gave 4 groups of participants different lists of words to remember
group 1 - acoustically similar
group 2 - acoustically different
group 3 - semantically similar
group 4 - semantically different
he asked the participants to recall the words in correct order (once immediately after and once after 20 mins)
what did Baddeley find?
immediately after, worst recall was from accoustically similar
after 20 mins, worst recall was from semantically similar
what is the capacity for short term memory?
7 +/- 2 items
who researched STM capacity?
Jacobs (1887) / Miller (1956)
what was Jacobs’ method?
digit span
used a sample of 443 female students (aged 8-19)
participants had to repeat back string of numbers/letters in the same order which was gradually increased until they could no longer recall
what was Jacobs’ results?
number digits - mean of 9.3 items
letters - mean of 7.3 items
what was Miller’s method?
observed that lots of sets of info that is used are sets of 7 so concluded that capacity was about 7 items
also noticed people could remember words as well as letters - he concluded his chunking theory
what is the duration of STM?
15 - 30 seconds
who researched STM duration?
Peterson + Peterson (1959)
what was Peterson + Peterson’s method?
tested 24 students
each was given 2 slips of paper - one with 3 letters and one with 3 digit number
participants had to read and remember the letters but had to countdown from the number immediately after (to prevent recall)
asked to stop counting down after specific times and asked to recall
what was Peterson + Peterson’s results?
3 seconds - 80% of trigrams correctly recalled
18 seconds - 10% correctly recalled
what is capacity of LTM?
unlimited
what is duration of LTM?
unlimited
who researched duration of LTM?
Bahrick et al (1973)
what was Bahrick et al’s method?
392 participants from Ohio (age 17-74)
asked them to recall past students from their yearbooks
tested on: photo recognition and free recall
what was Bahrick et al’s results?
photo recognition (15 years after) - 90% accurate
(48 years after) - 70% accurate
free recall (15 years after) - 60% accurate
(48 years) - 30% accurate
what’s a strength of Baddeley’s research?
identified a clear difference between two memory stores
led to MSM (real life application)
what’s a limitation of Baddeley’s research?
uses artificial stimuli
low external validity
limited application
what is a strength of Jacob’s study?
has been replicated (by Bopp + Verhaegen 2005)
has high validity
what is a limitation of Jacob’s research?
was conducted a long time ago
not to the scientifically rigorous standard for research as there is today
limits validity
what’s one limitation of Miller’s research?
may have overestimated
Cowan (2001) reviewed other research and concluded that it is only 4 +/- 1 chunks
What’s a limitation of Peterson + Peterson’s research?
artificial stimuli
lacks external validity
What’s a strength of Bahrick et al’s research?
high external validity
use meaningful stimuli
Shepard (1967) - used meaningless pictures and recall rates were lower
What’s a limitation of Bahrick et al’s study?
lacks internal validity
variables can’t be controlled
since a quasi experiment
what is a memory model?
a representation of what our memory might look like (since memory is a complicated concept it helps create a visual understanding)
Who came up with the multi store memory model (MSM)?
Atkinson and Shiffrin (1968)
what are the components of the MSM?
- sensory register
- short term memory
- long term memory
what are the processes of the MSM?
- retrieval
- attention
- transfer
- rehearsal
- forgetting
what are the types of sensory memory?
- iconic (sight/light)
- echoic (sound/auditory)
- haptic (touch)
- olfactory (smell)
- gustatory (taste)
what are the components of sensory memory?
duration = 1/2 second
capacity = 12 - 16 items
coding = from 5 senses
how is information transferred from the sensory register to STM?
attention
how is information transferred from STM to LTM?
maintance rehearsal
how is information transferred from LTM to STM?
retrieval
how can information be forgot?
if it isn’t rehearsed
from any store
what are strengths of MSM?
- supporting evidence from brain scans
- support from case studies (HM)
- evidence from Baddeley (coded seperatly)
what are limitations of MSM?
- too simplistic
- LTM requires more than just maintenance rehearsal
what is the case study of HM?
underwent brain surgery to treat epilepsy
hippocampus was removed from both sides of brain
he couldn’t form new long term memories but performed well on immediate memory span (STM)
what is elaborative rehearsal?
Craik + Watkins (1973)
occurs when new info is linked to existing knowledge
proves that LTM isn’t just from maintenance rehearsal
who came up with the idea that LTM has different stores?
Tulving (1985)
what part of the brain is episodic memory associated with?
hippocampus
what part of the brain is semantic memory associated with?
temporal lobe
what part of the brain is procedural memory associated with?
motor cortex and cerebellum
what is explicit memory?
information that has to be consciously worked to remember
what is implicit memory?
can be recalled with little effort
what are the types of declarative memory?
episodic memory
semantic memory
what is a strength of LTM stores?
supporting evidence from case studies (Clive Wearing)
what was the case study of Clive Wearing?
suffered brain damage from viral infection
lost his episodic memory but still has semantic and procedural memory
damage to his hippocamus
what is encoding specificity principle?
when a memory is stored so are the details of when and where
what is a weakness of Tulving’s ideas?
not operationalisable
its hard to define episodic and semantic memory in a measurable was
how developed the working memory model (WMM)?
Baddeley and Hitch (1974)
what are the three slave systems in the WMM?
- phonological loop
- visuo-spatial sketchpad
- episodic buffer
what is the central executive?
controls the WMM
all info passes to here then it decides which components should process it
components can only communicate with each other through here
what is the phonological loop?
holds info in the form of speech/sound
what is the visuo-spatial sketchpad?
concerned with visual and spatial info
what are the two parts of the phonological loop?
- articulatory loop
- phonological store
what does the articulatory loop do?
processes speech production + rehearses verbal info
what does the phonological store do?
deals with speech perception
what are the components of the visual-spatial sketchpad?
- inner scribe
- visual cache
what does the inner scribe do?
deals with spatial info
what does the visual cache do?
stores info about form, shape and colour
what is the episodic buffer?
temporary storage device used to integrate information from the phonologiocal loop and VSS
ensure all info from the slave systems link together and makes sense
added to the WMM in 2000
what is research to support the WMM?
- dual task studies
- case study of KF
what is the dual task study?
Baddeley + Hitch (1975)
participants were given visual tasks seperately then a visual and auditory task at the same time
- task performance decreased when tasks were the same (competeing for attention from the VSS)
what are strengths of the WMM?
- research to support the idea of sepearate components (dual task)
- extends on the work of the MSM
what are limitations of the WMM?
- too vague on link between STM and LTM
- difficult to measure central executive so not much is known about it
what is the case study of KF?
Shallice + Warrington (1970)
struggled to process ST auditory memory but could store visual ST memory
showed separate stores
what is interference?
occurs when two bits of info disrupt each other
so both or one bit of info is forgotten
what are the two types of interference?
- proactive
- retroactive
what is proactive interference?
when an old memory interferes with a new memory
what is retroactive interference?
when a new memory interferes with an old memory
whats the explanation for proactive interference?
previous info that is more similar to the new info makes the new info harder to stor
whats the explanation for retroactive interference?
the new info overrides the old info because of the similiarity
what research supports interfence?
McGeoch and McDonald (1931)
what was McGeoch and McDonald’s method?
participants had to learn a list of 10 words until there was 100% recall then they learn a new list
1. synonyms
2. antonyms
3. words unrelated to original ones
4. consonant syllables
5. three digit numbers
6. control (no list)
what was the findings and conclusions of McGeoch and McDonald?
when asked to recall original list - synonyms had worst recall
shows that inference is strongest when the memories are similar
what are strengths of inference theory?
- evidence of interference effects in everyday situations
- evidence of retrograde facilitation (drug studies)
what is the evidence of interference in everyday situations?
Baddeley + Hitch (1977)
asked rugby players to recall names of teams they have played against during a season
- players who played the most games had the poorest recall (more interference)
what is the evidence of retrograde facilitation?
Coenen and Luitelaar (1997)
gave participants lists of words and later asked them to recall it
- when lists were learnt under diazepam, recall one week later was poor
- when list was learnt before diazepam, later recall was better
whats the counterpoint of real world interference?
inference is unusual to cause forgetting in everyday situations
since two memories have to be fairly similar in order to interfere with eachother
what are limitations of interference theory?
- inference is only a temporary loss
- most studies are lab based so lacks external validity
what is evidence to suggest that inference is only a temporary loss?
Tulving + Pstka (1971)
- participants gave lists of words organised into categories
- given one list at a time
- recall averaged at 70% but got worse through the lists
- at the end they were told the names of the categories and asked to recall
- recall then rose to 70%
what is a cue?
a trigger of information that allows us to access a memory
they can be meaningful or indirectly coded at the same time of learning
what are the two types of non-meaningful cues?
- context-dependent forgetting (external)
- state-dependent forgetting (internal)
what evidence supports state-dependent forgetting?
Carter + Cassaday (1998)
- participants were split into groups and asked to recall a list sof words and a passasge
1. learn + recall on drug
2. learn on + recall off drug
3. learn off + recall off
4. learn off + recall on
findings: when internal states matched there was higher levels of recall
what is evidence to support context-dependent forgetting?
Godden + Baddeley (1975)
- prticipants learn list of words and asked to recall
1. learn land + recall land
2. learn land + recall water
3. learn water + recall land
4. learn water + recall water
- accurate recall was 40% lower in non-matching conditions
what are strengths of retrieval failure theory?
- real world application
- range of support
what are weaknesses of retrieval failure theory?
- may depend on the type of memory being tested (recall vs recognition)
- impossible to establish whether a cue has been encoded or not
what is the argument of recall vs recognition and a weakness of retrieval failure?
Godden + Baddeley (1980) - replicated their underwater study but participants had to say whether they recognised a word rather than recall it
recognition - no context dependent effect
suggests that retrieval failure is a limited explanation for forgetting since it only applies when a person has to recall info rather than recognise it
what is an eye witness testimony?
(EWT)
the ability of people to remember the details of events that they observed
what are factors affecting EWT?
- misleading information
- anxiety
how can misleading information affect EWT?
- leading questions
- post event dicussion
what is research on leading questions?
Loftus and Palmer (1974)
what was Loftus + Palmer’s procedure?
45 american uni participants
watch clips of car accident
were asked to describe how fast the cars were going when they (smashed/ bumped/ contacted ect) each other
what was Loftus + Palmer’s results?
smashed= 40.5 mph (mean estimate of speed)
bumped = 38.1 mph
contacted = 31.8 mph
why do leading questions affect EWT?
response bias - the wording doesn’t impact the participants’ memories but influences how they answered them
what was the results when Loftus + Palmer conducted a second EWT experiment?
when participants were asked with the word “smashed” they reported seeing broken glass on the floor (which wasn’t there)
what is research on post event dicussion?
Gabbert et al (2003)
what was Gabbert’s procedure?
60 uni students + 60 older adults
participants watched a video of a girl stealing money from a wallet
were tested individually (control) or in pairs (co witness group)
then all completed questionaire to test their memory of the event
what was the findings from Gabbert’s research?
0% in control group made errors
71% in paired group mistakenly recalled aspects of the video
why does post event discussion effect EWT?
- memory contamination
- memory conformity
what is memory contamination?
when co-witnesses discuss it with each other they become altered or distorted since they combine (mis)information with their own memories
what is memory conformity?
witnesses often go along with each other (to win social approval or they believe the other is right)
the actual memory is unchanged
what is the real world application of misleading information?
has important practical uses in the criminal justice system
protects innocent people from faulty convictions based on unreliable EWT
what are limitations of misleading information affecting EWT?
- evidence against substitution
- evidence challenging memory conformity
what is evidence against substitution as a limitation for misleading information?
EWT is more accurate for some aspects of an event for others
Sutherland + Hayne (2001) - found recall was more accurate for central details of the event rather than for the peripheral ones
suggests original memories for central details are less likely to be distorted
what is evidence challenging memory conformity?
the memory itself is distorted through contamination by misleading PED rather than the result of memory conformity
why does anxiety have a negative effect on recall?
weapon focus
- there is a focus on the weapon so reduces a witness’s recall for other details of the event
what research supports that anxiety has a negative impact on recall?
Johnson + Scott (1976)
what was Johnson + Scott’s procedure?
participants believed they were taking part in a lab study
low anxiety condition) heard a causal convo and saw a man walk past with a greasy pen
high anxiety condition) heard a heated argument + breaking glass and saw a man walk past with a bloody knife
participants then had to pick out the man from 50 photos
what was Johnson + Scott’s findings?
pen condition = 49% correctly identified him
knife condition = 33% correctly identified him
supports tunnel theory of memory which argues that people have enhanced memory for central events
what is a limitation of Johnson + Scott’s study?
it may not have tested anxiety, participants may have been surprised not scared
Pickel: eyewitness accuracy was poorer in high unusualness conditions
doesn’t tell us anything specifically about the effects of anxiety on EWT
what’s the support for Johnson + Scott’s study?
Valentine + Mesout (2009)
used heart rate to divide participants
showed that anxiety clearly disrupted the ability to recall details about the actor in the London Dungeons
why does anxiety have a positive effect on recall?
anxiety triggers the fight or flight response (physical arousal) which increases alertness
this improves memory since we are aware of more cues in the situation
what research supports that anxiety has a positive effect on recall?
Yuille + Cutshall (1986)
what is Yuille + Cutshall’s procedure?
13 witnesses from an actual shooting in Canada
interviewed 4 - 5 months after incident and compared with original police interviews from the time of the shooting
were asked to rate how stressed they and felt at the incident (7 point scale) and whether they had had any emotional problems since
what was Yuille + Cutshall’s findings?
participants that reported highest levels of stress were most accurate (88%) than lowest stress levels (75%)
what explains the contradictory findings in effects of anxiety?
Yerkes- Dodson law (1908)
what is Yerkes- Dodson’s law?
medium arousal is the optimum point for maximum recall
what is a limitation of Yuille + Cutshall’s research?
field studies often lack control
low internal validity
many things could have occurred between the incident and the interview that researchers have no control over
many extraneous variables
what research support Yuille + Cutshall’s findings?
Christainson + Hubinette (1993)
interviewed 58 witnesses to actual bank robberies in Sweden
some were directly or indirectly involved in the robberies
recall was more than 75% across all witnesses with direct victims even more accurate
BUT lack of control over co-founding variables since interviews were conducted 4 - 15 months after the incident
who proposed the cognitive interview?
Fisher + Geiselman (1992)
what are the steps in the cognitive interview?
- report everything
- reinstate the context
- reverse the order
- change perspective
what is report everything?
free recall
witnesses encouraged to include every detail , even if they seem insignificant (since they may act as clues )
what is reinstate the contect?
witnesses are told to return to crime scene in their mind
should imagine their environment and emotions
related to context dependent forgetting and cues
what is reverse the order?
witnesses asked to recall the event in different order
reduces likelihood of reporting false details
prevents dishonesty since its harder to lie in reverse
what is change the perspective?
witnesses asked to recall event from another persons perspective at the event
prevents the effect of schemas on recall
what is the evidence that the cognitive interview works?
Kohnken et al (1999)
meta analysis from 55 studies
CI gave average 41% increase in accurate information compared to standard interviews
but was also increase in amount of inaccurate information recalled
what is a limitation of the cognitive interview?
- that not all of its elements are equally useful or effective
- time consuming + takes more training
who came up with the enhanced CI?
Fisher (1987)
what were the elements added in the enhanced CI?
- eye contact (reduce eyewitness anxiety)
- minimising distractions (keep interview on topic)
- open ended questions
