Memory Flashcards
What is coding?
How you store and retrieve memories
What is capacity?
How much information you can store
What is duration?
How long you can store information
How does STM code?
Acoustically
How does LTM code?
Semantically
What was Baddeley’s experiment in coding?
Tested immediate recall and recall after 20 minutes
Using acoustically and semantically similar and dissimilar words
Immediate recall was worse with acoustically similar - STM codes acoustically
Recall after 20 minutes was worse with semantically similar - LTM codes semantically
What is the capacity of STM?
7 +/- 2 chunks of information
What is the capacity of LTM?
Unlimited
What was Jacob’s experiment into the capacity of STM?
Researcher reads digits and increases until participant cannot recall order correctly
Final number = digit span
Numbers = 9
Letters = 7
What is the duration of STM?
18-30 seconds
What is the duration of LTM?
Unlimited
48+ years
What was Peterson and Peterson’s experiment into duration
24 students given consonant syllable (e.g. YCG) to recall and 3-digit number to count backwards from
Retention interval varied (3, 6, 9, 12, 15, 18)
After 3 seconds = average recall 80%
After 18 seconds = average recall 3%
What are the three types of LTM?
Semantic
Procedural
Episodic
What is semantic LTM?
Memories of facts and knowledge
Is there effort needed to remember semantic memory?
Yes
Is there time stamping in semantic memory?
No
What detail is included in semantic memory?
Some will have context (remember when you learnt it) but mainly don’t
What brain area is semantic LTM in?
Frontal lobe
What is procedural LTM?
Memory of skills and actions
Muscle memory
Is there effort needed to remember procedural LTM?
No
Is there time stamping in procedural LTM?
No
What detail is included in procedural LTM?
Step by step instructions of personal experience
What brain area is procedural LTM in?
Cerebellum
What is episodic LTM?
Personal memories of events
Is there effort needed to recall episodic LTM?
Yes
Is there time stamping in episodic LTM?
Yes
What detail is included in episodic LTM?
Context and emotion
What brain area is episodic LTM in?
Frontal and temporal lobe
What type of LTM is the hardest to forget?
Procedural
What type of LTM is easiest to forget?
Semantic
Strength of types of LTM - research support
Got participants to perform various memory tasks while having their brains scanned by PET scanner
Semantic and episodic memories in pre-frontal cortex
Episodic memories in frontal and temporal lobe
Semantic in frontal lobe
Procedural in cerebellum
Limitation of types of LTM - only two types
Cohen and Squire
Procedural is separate but episodic and semantic stored together in one LTM store
Episodic and semantic = declarative memory
Procedural = non-declarative memory
Strength of types of LTM - practical application
Episodic memories could be improved in older people who had mild cognitive impairment
Benefits of being able to distinguish between types of LTM
Enables specific treatment to be developed
Strength of types of LTM - Clive Wearing
Cannot convert STM to LTM
Episodic LTM damaged
Procedural LTM in tact
Strength of types of LTM - HM case study
Had hippocampus removed due to epileptic fits
LTM significantly impaired
Semantic and procedural in tact
Episodic severely impaired
Counterpoint types of LTM - HM case studies
HM had brain damage which means it’s difficult to know exact parts which had been affected
Damage may not be exact cause of memory loss
Unable to conclude causal relationship between brain area and type of LTM
What does MSM stand for?
Multi-Store Model of Memory
What is the MSM?
Describes how information flows through the memory system
What does the MSM look like
Stimulus from environment
↓
Sensory register
↓ attention
STM
↓ maintenance rehearsal
↑ retrieval
LTM
What is the sensory register?
All stimuli from the environment pass into the SR
Part of memory is not one store but five, one for each sense (iconic, echoic)
How does the sensory register code?
Modularity specific, depends on the sense
Iconic = visual, echoic = acoustic
What is the duration of the sensory register?
Very brief
Less than half a second (250ms)
What is the capacity of the sensory register?
Very high (over one hundred million cells in one eye, each strong data)
How does information transfer from SR to STM?
Information passes further into memory only if ATTENTION is paid to it
What are the three characteristics of STM?
Coding = acoustic
Duration = 18 seconds unless information rehearsed
Capacity = 7 +/- 2 times before some forgetting occurs
What is the transfer from STM to LTM?
Maintenance rehearsal
What is maintenance rehearsal?
Occurs when we repeat (rehearse) material to ourselves
Can keep information in STM as long as we rehearse it
If rehearse it for long enough, passes into LTM
What are the three characteristics of LTM?
Coding = semantic
Duration = potentially unlimited
Capacity = potentially unlimited
What is the transfer from LTM to STM?
Retrieval
What is retrieval?
When we want to recall information stored in LTM, has to be transferred back to STM by a process called retrieval
Limitation of MSM - different types of LTM
Only includes one type of LTM
Semantic, procedural, episodic
Clive Wearing
- episodic damaged
- semantic and procedural in tact
Limitation of MSM - more than one type of rehearsal
Elaborative rehearsal
Add meaning to it, which allows information to be stored in LTM
Strength of MSM - research support
Baddeley
Mix up words that sound similar using STM (acoustic)
Mix up words that have similar meanings using LTM (semantic)
STM and LTM separate
Limitation of MSM - more than one STM
KF case study
Amnesia after motorcycle accident
STM recall for digits poor when heard but better when read
Separate STM for visual and auditory
What does WMM stand for?
Working Memory Model
What is the WMM?
Central Executive
↓
Phonological loop, Episodic buffer, Visuo-spatial sketchpad
↓
LTM
What is the central execute?
In charge of WMM
Takes in incoming information
Decides which STM system is going to code the information
What is the capacity of the central executive?
Very limited
How does the central executive?
Visual and auditory
What is the phonological loop?
Preserves the order in which information arrives
Deals with auditory information (what you hear)
Allows for maintenance rehearsal
How does the phonological loop code?
Auditory
What is the capacity of phonological loop?
2 seconds of what you say
What is the visuo-spatial sketchpad?
Records arrangement of objects in visual field
What is the visuo-spatial sketchpad?
Records arrangement of objects in visual field
How does the visuo-spatial sketchpad code?
Stores visual information
What is the capacity of the visuo-spatial sketchpad?
3-4 objects
What is the episodic buffer?
Temporary store for information
How does the episodic buffer code?
Visual and auditory
What is the capacity of the episodic buffer?
4 chunks of information
Strength of WMM - KF case study
Suffered brain damage after motorbike accident
Had poor STM for verbal information but could process visual information normally
Verbal information = phonological loop
Visual information = visuo-spatial sketchpad
Strength of WMM - practical application
Create diagnostic tools for neurodivergent conditions such as ADHD
Help in educational settings, creating support/resources to ensure people with ADHD have full access to education
Strength of WMM - research support
Baddeley’s dual task study
Must be separate components processing visual and verbal information
Found it hard to carry out two visual tasks at the same time than to do a visual and verbal task
Both visual tasks compete for same subsystem
Limitation of WMM - reductionist
MSM detailed about process of how information moves to each store whereas WMM isn’t
Limitation of WMM - lack of clarity
Baddeley
Central executive is most important but the least understood component of working memory
Must be more to central executive than ‘attention’
Unsatisfactory component and challenges integrity of WMM
What does EWT stand for?
Eye Witness Testimony
What is EWT?
A retelling of something that happened by someone who witnessed it
What are the factors affecting EWT?
Anxiety
Leading questions
Post-event discussion
What is Yerkes-Dodson law?
Low anxiety means you won’t pay attention
High anxiety means you’re overwhelmed
What effect did Johnson and Scott believe anxiety had?
Negative
What was the procedure of Johnson and Scott’s experiment?
Participants sat in waiting room, believing they were going to take part in lab study
Participants then asked to pick man from set of 50 photos (STM)
Low-anxiety = casual conversation, man walked through with pen and grease on hands
High-anxiety = heated argument, man walked through with knife and blood on hands
What were the results of Johnson and Scott’s experiment?
49% identified in low anxiety
33% identified in high anxiety
Tunnel theory of memory argues people have enhanced memory for central events
Weapon focus as a result of anxiety can have this effect
What is weapon focus?
Tunnel theory of memory where individual focuses on weapon and ignores other details
What effect did Yuille and Cutshall believe anxiety had?
Positive
What was the procedure of Yuille and Cutshall’s experiment?
In an actual crime, gun-shop owner shot a thief dead (natural experiment)
13/21 witnesses participated in experiment
Interviewed 5 months after incident and information recalled compared to police interviews at the time (LTM)
Witnesses rated how stressed they were at time of incident
What were the results of Yuille and Cutshall’s experiment?
Witnesses very accurate in what they recalled and there was little change after 5 months (age/weight/height less accurate)
Participants with highest level of stress were more accurate (88% - 75% in less-stressed group)
Anxiety doesn’t appear to reduce accuracy of EWT in real-world event and may enhance it
Strength of anxiety in EWT - practical application
Enhanced cognitive interviews
Limitation of anxiety in EWT - alternative explanations
Pickel et al
Unusualness rather than anxiety caused poor recall
Participants had poor recall of a hairdresser’s video when raw chicken and gun shown
What are leading questions?
A question phrased in a certain way to lead you to a certain answer
Closed questions
Do leading questions increase or decrease the accuracy of EWT?
Decrease
What was the procedure of Loftus and Palmer’s experiment?
Participants individually watched the same value
Each participant asked a question with a critical word - verb
Verbs: smashed, contacted, hit, collided, bumped
What were the results of Loftus and Palmer’s experiment?
Smashed had highest speed estimate in mph (40.5)
Contacted had lowest speed estimate in mph (31.8)
Strengths of Loftus and Palmer experiment
Reduced demand characteristics - distractor questions, independent groups design
Standardised - same car crash video
Limitations of Loftus and Palmer experiment
No protection from harm - cannot replicate to check validity
Low confidence sample - most students didn’t drive, driving experience = confounding variables
Strength of leading questions - research support
Participants came back a week later and asked a series of questions
Critical leading question was “Did you see any broken glass?”
32% who had “smashed” as verb reported seeing broken glass
14% of who “hit” reported seeing broken glass
What is post-event discussion?
A conversation after an event
Does post-event discussion increase or decrease the accuracy of EWT?
Decrease
What type of experiment did Gabbert conduct?
Lab
What was the procedure of Gabbert’s experiment?
Paired participants watched a video of the same crime but from different perspectives so they could see elements the other couldn’t
Participants discussed what they’d seen on the video before individually completing a test of recall
Control group - no discussion and no errors
What was the sample of Gabbert’s experiment?
60 students and 60 older adults
What were the results of Gabbert’s experiment?
71% of participants wrongly recalled aspects of the event they didn’t see but heard in the discussion
60% of people said someone had committed the crime even though they didn’t see it
Evidence of memory conformity
What is memory contamination?
When eye witnesses have influence each other
Strength of post-event discussion - Gabbert’s experiment
Lab experiment
High control of variables
Limitation of post-event discussion - Gabbert’s experiment
Lacks ecological validity
Not prepared to see a crime in real-life
Can’t dictate how long a discussion it
Strength of post-event discussion - practical application
Advise police officers to separate witnesses as soon as possible and educate witnesses
Bodna’s research
- educate eye-witnesses about post-event discussion and its negative impact
- reduces memory conformity and increases accuracy of eye-witnesses
Strength of post-event discussion - research support
Paterson and Kemp
Asked participants to watch a crime and then were given 1 or 4 pieces of information
Leading questions, media report, third party post-event discussion, co-witness post event discussion
Post-event discussion more influential than the media report or leading questions
What are the types of cognitive interview?
Report everything
Reinstate the context
Change perspective
Reverse order
What is a report everything cognitive interview?
The eyewitness must state all information even if they think it is INSIGNIFICANT OR IRRELEVANT
How does a report everything cognitive interview improve EWT?
Recall all information even if it seems insignificant
Trigger further memories
What is a reinstate the context cognitive interview?
Eye witnesses MENTALLY go back to the scene of the crime
How does a reinstate the context cognitive interview improve EWT?
Adds cues to help the witness retrieve information
What is a change perspective cognitive interview?
Ask the eye-witness to report the crime from another person’s perspective, i.e. VICTIM OR CRIMINAL
How does a change perspective cognitive interview improve EWT?
To help the witness add detail to their statement
What is a reverse order cognitive interview?
Ask the eyewitness to state the crime in a NON-CHRONOLOGICAL order, i.e. from the end of the crime to the beginning
How does a reverse order cognitive interview improve EWT?
Reduces the likelihood of false information being stated
STOPS SCHEMAS
What is an enhanced cognitive interview?
Usually for victims
Informal
Reduce anxiety
Open questions
Build trust/rapport
Strength of cognitive interviews - ethical to use
Research into effectiveness of CI technique has been useful in improving the interview techniques in Brazil where people traditionally use interrogation, torture and ill treatment
Findings suggest CI technique could be used to develop new approach in interviewing witnesses in Brazil
Lead to reduction in amount of miscarriages of justice
Limitation of cognitive interviews - practicality
Takes longer than standard police interview
Eyewitnesses may have to wait longer to give their report
Money = costs to train police officers and costs more in terms of working hours
Limitation of cognitive interviews - different procedures
Thames Valley Police don’t use “changing perspectives”
Others tend to use only “reinstate the context” and “report everything”
What is the encoding specificity principle?
If a cue is to help us to recall information it has to be present at encoding and retrieval
We need the cue to find a memory
What are the types of cue?
Context-dependent
State-dependent
What is a context-dependent cue?
Location
If location is different to when you learnt it and when you are trying to retrieve it, you will forget
What was Godden and Baddeley’s research?
Group 1 = learn on land, recall on land
Group 2 = learn underwater, recall on land
Group 3 = learn on land, recall underwater
Group 4 = learn underwater, recall underwater
Groups 2 and 3 forgot more information than 1 and 4
What is a state-dependent cue?
How you feel
If the state you are in when you retrieve information is different to when you learn, you will forget
What was Carter and Cassidy’s research?
Gave participants anti-histamine tablets which makes them drowsy
Group 1 = learn on drug, recall on drug
Group 2 = learn not on drug, recall on drug
Group 3 = learn on drug, recall not on drug
Group 4 = learn not on drug, recall not on drug
Groups 2 and 3 forgot more information than 1 and 4
Limitation of retrieval failure - ecological validity
In the real world, location differences aren’t that extreme
Real world application
Lacks ecological validity
Strength of retrieval failure - research support
Baker et al
Students randomly placed in 4 groups
Group 1 = learn chewing gum, recall chewing gum
Group 2 = learn chewing gum, recall not chewing gum
Group 3 = learn not chewing gum, recall chewing gum
Group 4 = learn not chewing gum, recall not chewing gum
Immediate recall showed little differences
After 24 hours
- group 1 = 11 words
- group 2 = 8 words
- group 3 = 7 words
group 4 = 8.5 words
What is interference?
One memory blocking access to another memory
What are the types of interference?
Retroactive
Proactive
What is retroactive interference?
When a new memory interferes with an old memory
What is proactive interference?
When an old memory interferes with a new memory
When is interference worse?
When information is similar
Strength of interference - research support
Baddeley and Hitch
Asked rugby players to recall names of teams they’d played against during rugby season
More games they’d played (more interference), poorer the recall
Shows interference operates in same everyday solutions, increasing validity
Limitation of interference - alternative explanation
Tulving and Psotka
Gave participants list of words organised into categories (not told what they were)
Recall of first list was 70% but fell with each new list (interference)
When given a cued recall list (names of categories), recall rose again to 70%
Interference causes just a temporary loss of access to material still in LTM - retrieval failure
Strength of interference - drug studies support
Material learnt just before taking diazepam recalled better than a placebo group a week later (retrograde facilitation)
Drug stopped new information reaching brain areas that process memories so it could not retroactively interfere with stored information
