Memory Flashcards
What is the multi-store model?
- A representation of how memory works in terms of three stores:
the sensory register, STM, and LTM
What does the MSM model consist of
- Stimulus from the environment
- Sensory register: the memory stores for each
of our 5 senses, such as vision (iconic store)
and hearing (echoic store) - STM store
- LTM store
- Retrieval and rehearsal help info pass between STM and LTM
- Attention is the key process
What does the sensory register consist of?
- All stimuli from the environment passes into the sensory register (SR)
- Iconic memory store codes for visual info, and echoic memory store codes acoustically
- Coding in each store is modality-specific (depends on the sense)
- Duration of material in the SRs is very brief – less than half a second - Very high capacity
- Info passes further into the memory system only if you pay attention to it
What is short-term memory (STM)?
- The limited- capacity memory store - can only contain a certain amount of things before forgetting occurs - Coding is mainly acoustic (sounds), capacity is between 2 and 9 items,
- Duration is about 18s unless maintenance rehearsal occurs
- Prolonged rehearsal passes info from STM -> LTM
What is long-term memory?
- The permanent memory store
- Coding is mainly semantic (meaning)
- It has unlimited capacity and can store memories for up to a lifetime
- To recall info from LTM it has to be transferred to STM by retrieval
What is coding?
How does coding work in the STM and LTM?
The format in which information is
stored in the various memory stores
- STM: prefers to code acoustically
- LTM: prefers to code semantically
Who researched coding and what did they find?
- Baddeley gave different lists of words to four groups of participants to
remember:
Group 1 (acoustically similar); Group 2 (acoustically dissimilar); Group 3 (semantically similar); Group 4 (semantically dissimilar) - STM did worse recalling acoustically similar and LTM (after 20mins) did worse with semantically similar
STM -> codes acoustically
LTM -> codes semantically
What is capacity?
What is the capacity in the STM and LTM?
- The amount of information that can be held in a memory store
- STM: 7+/- 2 items
- LTM: unlimited
Which two psychologists researched capacity and what did they find?
- Digit span (Jacobs): asked participants to recall 4 digits and adds one until the participants can’t recall the order correctly
- Mean digit span- 9.3
- Letter span- 7.3
- Span of memory and chunking (Miller): made observations of everyday practice and saw that many things come in 7s (days of the week etc) - span of STM is 7+/- 2
What is duration?
What is the duration of the STM and LTM?
- The length of time information can be held in memory
- STM: 18-30s
- LTM: up to a lifetime
What is decay?
The automatic fading of memory that’s not rehearsed -> causes information loss from the STM
Who researched STM duration?
- STM duration (Peterson & Peterson): tested 24 students in 8 trials each
- On each trial the student was given a consonant syllable and a 3-digit number to remember
- Students counted backwards from this number until told to stop
- On each trial they were told to stop after varying periods of time: 3, 6, 9, 12, 15 or 18s (retention interval).
- After 3s: 80% recall and after 18s: 3% -> STM duration = 18s
Which psychologist researched LTM duration?
- Bahrick et al studied 392 American participants aged 17-74
- Tested recall with high school yearbooks through: photo recognition test, and free recall test of names
- Photo recognition:
15yrs= 90% accuracy
48yrs= 70% - Free recall:
15yrs= 60%
48yrs= 30% - LTM duration may last up to a lifetime
What is a strength and weakness of research into coding? (AO3)
+ Separate memory stores: Baddeley identified a clear difference in coding for the stores - important step in our understanding of the memory system-> MSM
- Artificial stimuli: Baddeley’s word lists were meaningless to participants - tells us little about coding in everyday life -> limited application
What is a strength and weakness of research into capacity?
+ Valid study: has been replicated - old study and early psychological research lacked adequate controls (underestimated digit spans - confounding variables) -> Jacob’s findings were confirmed by Bopp and Verhaegen
- Miller may have overestimated STM capacity: Cowan (2001) reviewed other research and concluded that STM capacity is only 4 +/- 1 chunks
What is a strength and weakness of research into duration?
+ High external validity: Bahrick et al used meaningful memories-> reflects a more real estimate of LTM duration
- Artificial stimuli: Peterson & Peterson used consonant syllables - doesn’t reflect most everyday memory activities where we try to remember meaningful things (phone numbers are meaningless - not completely irrelevant study) -> lacks external validity
What is a strength of the MSM? (A03)
- Research support: that shows the difference between STM and LTM
- E.g. Baddeley found that STM codes acoustically and LTM codes semantically - adds internal validity
What are the weaknesses of the MSM?
- There is more than one type of STM - Shallice and Warrington studied amnesia patient KF -> found that his memory for digits was poor when read to him but improved when he read them himself ->STM store for sounds & images
- Prolonged rehearsal is not needed - in the MSM what matters is the amount of rehearsal you do -> Craik and Watkins found that type of rehearsal matters (maintenance & elaborative=needed for LTM storage) -> partial explanation
- There is more than one type of LTM: we have a LTM store for episodic, procedural, and semantic memories -> contradicts MSM view that there are only 3 types of memory stores
- Reductionist: reduces complex memory processes to simple storage systems + ignores qualitative aspects of memory e.g. influence of emotions, schemas on encoding & retrieval
- Artifical research methods: lab studies
Who proposed that there were 3 types of LTM and what are they?
Tulving:
- Episodic
- Semantic
- Procedural
What is episodic memory?
- Refers to our ability to recall events from our lives
- e.g. first day of school
- Time stamped
- Contain several elements
- Require conscious effort to recall
What is semantic memory?
- Refers to our knowledge of the world
- e.g. capital cities
- Less personal and based on facts of the world
- Requires conscious effort
What is procedural memory?
- Refers to our memory for actions, skills, and how to do things
- e.g. walking, writing
- Automatic and requires no conscious effort to recall
What are the strengths of the different types of LTM (A03)?
- Clinical evidence: case studies of HM (understood concept of dogs but couldn’t recall earlier stroking one) and Clive Wearing (pianist) - episodic memory of both was impaired due to brain damage -> had difficulty recalling past events but procedural (knew how to walk & speak) & semantic were still intact
- Real-world application: the ability to identify different types of LTM has allowed psychologists to target certain kinds of memory to better lives -> Belleville et al devised an intervention to improve episodic memory in older people -> found that episodic memories could be improved in older people who had a mild cognitive impairment (trained ppts did better than control=no memory training, on episodic test)
What are the weaknesses of different types of LTM? (A03)
- Conflicting neuroimaging evidence: Buckner & Petersen - reviewed evidence on the location of semantic/episodic - found that semantic is on the left of the prefrontal cortex but other research by Tulving links episodic encoding to the left - poor agreement
- Evidence to suggest episodic and semantic store are the same: Tulving’s research showed that people with amnesia have a functioning semantic alongside a damaged episodic - believes episodic memory is a specialised subcategory of semantic
- Reliance on Case Studies: Clive Wearing - could play the piano (procedural memory) but had severe episodic memory loss -> offers rich qualitative data - lacks generalisability - findings are based on unique individuals with specific brain injuries -> difficult to apply conclusions to the general population
- Artificial research methods: experimental studies often use artificial tasks to test different types of LTM, such as learning word lists (semantic memory)
What is the working memory model?
An explanation of how STM is organised and functions
What does the working memory model consist of?
- Central executive
- Episodic buffer
- Phonological loop
- Visuo-spatial sketchpad
What is the role of the central executive?
- Monitors incoming data
- Focuses and divides our limited attention
- Allocates subsystems to tasks
- Limited processing capacity and does not store information.
What is the role of the episodic buffer?
- A temporary store for information, integrating the visual, spatial, and verbal information processed by other stores and maintaining a sense of time sequencing
- Storage component of the CE
- Limited capacity
of about four chunks (Baddeley) - Links working memory to LTM
What is the role of the phonolgical loop and what does it consist of?
- Deals with auditory information (codes acoustically) and preserves the order in which the information arrives
- Phonolgical store: stores the words you hear
- Articulatory process: allows maintenance rehearsal - capacity = 2s of what you can say
What is the role of the visuo-spatial sketchpad and what does it consist of?
- Stores visual and/or spatial information when required
- Limited capacity, which according to Baddeley (2003) is about 3 or 4 objects
- Visual cache: stores visual data.
- Inner scribe: records the arrangement of objects in the visual field
What are the strengths of the working memory model? (A03)
- Clinical evidence: Shallice & Wallington case study of brain damage patient KF -> poor STM ability for verbal info but could process visual info (his immediate recall of digits/letters was betteer when he read them) - his phonoloigcal was damaged but other areas of memory still intact
- Dual-task performance: Baddeley et al’s particpants carried out a visual & verbal task at the same time (performance was similar to separated) - when both were visual/verbal (tracking a light + describing the letter F), performance declined as they are competing for the same subsystem - supports the separate existence of the visuospatial sketchpad.
What are the weaknesses of the working memory model (A03)
- Lack of clarity over the nature of the central executive: Baddeley said, ‘The central executive is the most important but the least understood component of working memory’ -> needs to be more clearly specified than just being simply ‘attentional process’ - the CE is an unsatisfactory component and other psychologists believe it may consist of separate components
- Nomothetic: attempts to generate universal laws about how STM processes info, based on dual task studies in lab conditions - using an idiographic approach e.g. Sachs with Clive Wearing shows how STM loss varies between people -> idiographic approach alongside nomothetic = further understanding
- Lacks external validity: these studies use tasks that are unlike everyday tasks (e.g. recalling random sequences of letters) -> also carried out in highly controlled lab conditions
What is proactive interference?
Where past information hinders your ability to recall new information
e.g. calling your new teacher by your old teacher’s name
What is cue overloading?
A retrieval cue is associated with multiple different memories
What is retroactive interference
Where recent information hinders your ability to recall older information
e.g. learning new A-Level content has made you forget your GCSE content
Who conducted research into the effects of similarity on interference and what did they found?
- McGeoch and McDonald studied retroactive interference by changing the amount of similarity between two sets of materials
- Participants had to learn a list of 10
words until they could remember them with 100% accuracy - Divided into 6 groups and had to learn a new list of e.g. synonyms, antonyms
- Interference is strongest when the memories are similar
What are the strengths of the interference explanation for forgetting? (A03)
- Real-world interference: Baddeley & Hicth asked rugby players to recall the names of the teams they had played against during a rugby season - all played for the same time interval but some players missed matches due to injury - >players who played the most games (most interference) had the poorest recall -> validity
- Counter: unusual in everyday situations as lab studies can create ideal conditions for intereference - memories have to be fairly similar -> most forgetting is better explained by other theories
- Research support: many lab experiments have been carried out into this explanation of forgetting (McGeoch & Mcdonald) ->lab experiments control extraneous variables so it’s a valid explanation
- Real-World applications: applied to practical settings, e.g. explaining revision strategies for students (e.g., avoiding studying similar subjects back-to-back) & understanding how information overload impacts memory in the workplace -> ecological validity
What are the weaknesses of the interference explanation for forgetting (A03)
- Interference can be overcome using cues: Tulving & Psotka gave participants lists of 24 words in 6 non-obvious categories -> recall was 70% for 1st list but became worse as participants learned each additional list -> recall rose to 70% again when given cued recall test - interference causes a temporary loss of
accessibility to LTM material - Artificial stimulus material: most studies use word lists - more mundane realism than consonant trigrams but doesn’t accurately represent everyday memory
What is the retrieval failure explanation for forgetting?
It occurs when we don’t have the necessary cues to access a memory - the memory is available but not accessible unless a suitable cue is provided
What is a cue?
A trigger of information that allows us to access a memory
What is ESP (Encoding Specificity Principle)?
What is context-dependent forgetting?
What is state-dependent forgetting?
What are the strengths of the retrieval failure explanation for forgetting? (A03)
Real-world application: Baddeley suggests cues may not have a strong effect but are still worth paying attention to -> when we have trouble remembering something it’s worth trying to recall the environment you learned it first - research reminds us of strategies we can use in real-world to improve recall
Research support: Baddeley & Godden + Carter & Cassaday studies show that a lack of relevant cues at recall can lead to state & context-dependent forgetting in everyday life
Holistic: provides a more holistic explanation of forgetting compared to interference, as it considers the interaction between memory and environmental/ internal cues -> aligns with the understanding that memory is influenced by a range of contextual factors
Internal validity: experiments investigating retrieval failure, e.g. those using context & state-dependent memory, often take place in controlled lab settings -> ensures extraneous variables are minimized -> reliability
What are the weaknesses of the retrieval failure explanation for forgetting? (A03)
- Depends on the type of memory being tested (recall v recognition): Godden & Baddeley replicated their study with a recognition test instead of retrieval -> no context-dependent effect and performance was the same for all conditions
- Problems with ESP: not possible to establish whether a cue has been encoded or not (cause and effect) - reasoning is circular and based on assumptions -> reduces validity
What is eyewitness testimony?
The ability of people to remember the details of events, such as accidents and crimes, which they themselves have observed
What is misleading information?
Where incorrect information is given to an eyewitness usually after the event
What is a leading question?
A question which because of the way it’s asked suggests a certain answer
What are the two explanations for why leading questions affect EWT?
- The response-bias explanation: the wording of the question has no real effect on the participants’ memories, but just influences how they decide to answer e.g. when a participant gets a leading question using the word ‘smashed’ - encourages them to choose a higher speed estimate
- Loftus and Palmer conducted a 2nd experiment that supported the substitution explanation: the wording of a leading question changes the participant’s memory of the film clip -> participants who originally heard smashed were later more likely to report seeing broken
glass (there was none) than those who heard hit -> critical verb altered their memory
What did Loftus and Palmer investigate about leading questions?
(substitution explanation)
- Loftus and Palmer made 45 students watch film clips of car accidents and then asked them a leading question about how fast the cars were going. ‘About how fast were the cars going when they (hit/contacted/bumped/ collided/smashed) each other?’
- Findings: mean estimated speed for contacted was 31.8 mph. For smashed, the mean was 40.5 mph - The leading question biased the eyewitness’s recall of an event
What is post-event discussion and why does it affect EWT?
Occurs when there is more than one witness to an event - they may discuss what they have seen with co-witnesses/others -> could influence the accuracy of each witness’s recall
What research was conducted into PED and by who?
- Gabbert et al
- Studies ppts in pairs
- Each ppt watched a video of the same crime filmed from different POVs e.g. only one ppt could see the title of a book carried by a woman
- Both discussed what they’d seen before individually completing a test of recall
- 71% mistakenly recalled aspects of the event they didn’t see but picked up in PED -> 0% in a control with no discussion
- Memory conformity
What are the two explanations for why post-event discussion affects EWT?
- Memory contamination: when co-witnesses to a crime discuss it with each other, their EWT’s may become altered/distorted - they combine (mis) information from other witnesses with their own memories
- Memory conformity: Gabbert et al. concluded that witnesses often go along with each other, either to win social approval or because they believe the other witnesses are right and
they are wrong-> actual memory is unchanged
What is a strength of misleading information as a factor affecting EWT? (A03)
+ Important practical uses in the criminal justice system: Loftus believes leading questions can have a distorting effect on memory so police need to be careful when interviewing + psychologists can be asked to act as expert witnesses in court trials and explain the limits of EWT to juries - help to improve the way the legal system works + prevent faulty convictions
What are the weaknesses of misleading information as a factor affecting EWT? (A03)
- Evidence against substitution: EWT is more accurate for some aspects of an event than for others -> Sutherland & Hayne showed participants a clip and when later asked misleading questions, their recall was more accurate for central details of the event than for peripheral ones (resistant to misleading info) - og memories for central details survived
- Evidence challenging memory conformity: there is evidence that PED alters EWT -> Skagerberg & Wright showed participants 2 versions of a film clip (one with a mugger with dark brown hair and the other light brown) - participants discussed the clips in pairs and reported a blend of the two -> memory is distorted through contamination bymisleading PED, rather than memory conformity
How does anxiety have a negative effect on recall?
- It creates physiological arousal which prevents us from paying attention to important cues -> reduces recall
- Weapon-focus effect: the presence of a weapon creates anxiety -> leads to a focus on the weapon, reducing the witness’s recall for other details of the event
How did Johnson and Scott investigate the negative effect of anxiety on recall?
- Johnson & Scott’s participants believed they were taking part in a lab study
- While in a waiting room ppts in the low-anxiety condition heard a casual conversation, then saw a man walk past them carrying a pen + with greasy hands
- In the high anxiety condition participants overheard an argument, accompanied by the sound of breaking glass-> a man walked out of the room, holding a blood-covered knife
- Findings: out of a set of 50 photos, 49% in low-anxiety could identify the man -> 33% in high-anxiety could identify the man with knife
- Tunnel theory of
memory: people have enhanced memory for central events - weapon focus due to anxiety can have this effect
What is the tunnel theory?
Tunnel theory of memory: people have enhanced memory for central events - weapon focus due to anxiety can have this effect
How does anxiety have a positive effect on recall?
- Witnessing a stressful event creates anxiety through physiological arousal within the body
- The fight or flight response is triggered, increasing alertness
- May improve memory for the event as we become more aware of cues in the situation
How did Yuille and Cutshall investigate the positive effect of anxiety on recall?
- Yuille and Cutshall conducted a study where ppts were witnesses to a shooting in a shop - 21 witnesses, 13 took part in the study.
- Interviewed 4-5 months after the incident and these were compared with the original police interviews at the time of the shooting
- Witnesses were asked to rate how stressed they had felt at the time of the incident (on a 7-point scale) and whether they had any emotional problems since the event (e.g. sleeplessness).
- Findings: participants who reported the highest levels of stress were most accurate (88% compared to
75% for less-stressed group)
What is the inverted-U theory (Yerke Dodson’s law)
- The inverted-U theory looks at the relationship between emotional arousal and performance
- It states that performance will increase with stress, but only to a certain point, where it decreases drastically
- Deffenbacher found lower levels of anxiety=lower recall accuracy
What are the strengths of anxiety as a factor affecting EWT? (A03)
- Support for positive effects: Christianson & Hubinette interviewed 58 witnesses to actual bank robberies in Sweden (both directly & indirectly involved) -> 75% accuracy across all witnesses, and even more for the anxious direct victims
- Support for negative effects: Valentine & Mesout’s real-world setting study (Labryinth horror, London dungeon) - objective measure (heart rate) to separate conditions -> ppts completed questionnaires of their self-reported anxiety at the end of the visit + had to describe a person encountered in the horror show -> 17% of high-anxiety group identified correct actor compared to 75% of low-anxiety group
What are the weaknesses of anxiety as a factor affecting EWT? (A03)
- Johnson and Scott’s study may not have tested anxiety: Pickel conducted an experiment using scissors, a handgun, a wallet, or raw chicken as hand-held items in a hairdressing salon video - eyewitness accuracy was poorer in high unusualness conditions (chicken + handgun) -> weapon-focus effect is due to unusualness rather than anxiety
- Inverted-u explanation may be too simplistic: places emphasis on physical arousal & assumes this is the only aspect linked to EWT -> ignores that anxiety has many elements - cognitive, behavioural, + emotional factors
What is cognitive interview and what are the four main techniques?
A method of interviewing eyewitnesses to help them retrieve more accurate memories
-Report everythng
- Change perspective
- Reverse the order
- Reinstate the context
What is the ‘report everything’ technique?
- Witnesses are encouraged to include every single detail of the event, even though it may seem irrelevant
- Trivial details may be important and trigger other important memories
What is the ‘reinstate the context’ technique?
- The witness should return to the original crime scene ‘in their mind’ - imagine their environment + emotions
- Related to context-dependent forgetting
What is the ‘reverse the order’ technique?
- Events should be recalled in a different order from the original sequence e.g. from final point -> beginning
- Prevents people from reporting their expectations of how the event happened rather than reporting the actual events
- Prevents dishonesty
What is the ‘change perspective’ technique?
- Witnesses should recall the event from other people’s perspectives
- Disrupts the effects of expectations & schema on recall -> the schema you have of a particular setting may generate expectations of what would have happened
What is enhanced cognitive interview (ECI) and who developed it?
- Fisher et al developed some additional elements of the CI to focus on the social dynamics of the interaction
- Enhanced CI also includes ideas like reducing eyewitness anxiety, minimising distractions, open-ended questions, getting the witness to speak slowly
What are the strengths of cognitive interviews in helping improve the accuracy of EWT? (A03)
+ Support for the effectiveness of CI: Kohnken et al’s meta-analysis combined data from 50 studies comparing the CI with standard police interview -> CI gave an average 41% increase in accurate info compared with standard - effective technique
+ Variations of the CI: studies of the effectiveness of CI inevitably use slightly different techniques of the enhanced CI -> more flexible + allows individuals to develop an approach according to what works best for them
What are the weaknesses of cognitive interviews in helping improve the accuracy of EWT? (A03)
- The CI is time-consuming: police may be reluctant to use it as it takes more time than standard police interviews -> time to establish rapport + requires special training & many forces haven’t been able to provide more than a few hrs of training (Kebbel & Wagstaff) - unrealistic
- Not all elements are equally effective: Milne & Bull found each technique to produce more info than standard police interview - also found that using a combination report everything & context reinstatement produced better recall than all other conditions -> reduces credibility
