Memory Flashcards
Coding, Capacity and Duration of Memory- Research On Coding- AO1
- Coding- the format in which information is stored in the various memory stores
- Baddeley
Lists of words to four groups: acoustically similar/dissimilar and semantically similar/dissimilar - when recalled words immediately (STM)=worse with acoustically similar
- when recalled words after 20 minutes (LTM)=worse with semantically similar
- information coded acoustically in STM and semantically in LTM
Coding, Capacity and Duration of Memory- Research On Coding- AO3
- Separate memory stores +
STM using acoustic coding and LTM using semantic coding has stood test of time
Important step in understanding memory and led to multi-store model - Artificial stimuli -
Word lists=no personal meaning to participants
Findings don’t tell us about coding in everyday life
More meaningful info=semantic coding for STM?
Limited application
Coding, Capacity and Duration- Research On Capacity- AO1
- Capacity- amount of information that can be held in a memory store
- Digit span- Jacobs
Achieved through reading out increasing number of digits and measuring how many recalled correctly in a row
Mean digit span=9.3 items
Mean letter span=7.3 items - Span of memory and chunking- Miller
Things come in sevens: days of week, deadly sins, seas
Span of STM=7+-2
Do this by chunking
Coding, Capacity and Duration- Research On Capacity- AO3
- A valid study +
Jacob’s study replicated
Some studies=old and lack control/have confounding variables
Findings confirmed by better controlled studies - Not so many chunks -
Miller overestimated STM capacity
Cowan- capacity of STM=4+-1 items
Lower end of 7+-2 is more appropriate
Coding, Capacity and Duration- Research On Duration- AO1
- Duration- the length of time information can be held in memory
- Duration of STM- Peterson+Peterson
Consonant syllables to 24 p’s in 8 trials
Counted back from 3-digit number (to prevent mental rehearsal)
3 seconds=80% recall
18 seconds=3% recall
STM duration=18 seconds - Duration of LTM- Bahrick
High school yearbooks
Photo-recognition and free recall
15 years after graduation=90% photo recall / 60% free recall
48 years after graduation=70% photo recall / 30% free recall
LTM may last a lifetime
Coding, Capacity and Duration- Research On Duration- AO3
- Meaningless stimuli in STM study -
Even though remember some meaningless material (phone numbers)
Does not reflective everyday life when meaningful information
Lacks external validity (Peterson) - High external validity +
Bahrick investigated meaningful memories
LTM on meaningless info=lower recall
Reflect more real estimate of duration
Multi-Store Model- AO1
- Atkinson+Shriffin
- Sensory register
All stimuli from environment
Visual info=iconic memory store
Acoustic info=echoing memory store
Duration=<1/2 second
Capacity=very high
Info passes further if pay attention to it - STM
Coding=acoustic
Duration=18 seconds
Capacity=7+-2 items
Maintenance rehearsal=repeat material- stays in STM as long as rehearse
Rehearse long enough=LTM - LTM
Coding=semantic
Duration=up to lifetime
Capacity=practically unlimited
When recall from LTM, need to be retrieved to go into STM
Multi-Store Model- AO3
- Research support +
Baddeley- mix up similar words in STM, mix up similar meanings in LTM
STM and LTM are separate stores, as claimed by MSM - More than one STM store -
Shallice+Warrington- KF amnesia
STM digits=very poor when read out loud to him but recall better when read himself
Another memory store for non-verbal sounds - Elaborative rehearsal -
Craik+Watkins- type of rehearsal more important than amount
Elaborative rehearsal (link info to prior knowledge) needed for LTM
MSM does not fully explain how LTM achieved
Types of Long-Term Memory- AO1
- Tulving- MSM too simplistic/inflexible
Three LTM stores - Episodic memory
Personal events
Time-stamped- when/what happened
People, place, objects, behaviours
Conscious effort to recall memory - Semantic memory
Shared knowledge of world
Not time-stamped
Less personal- shared facts
Less vulnerable to distortion/forgetting
Deliberate recall - Procedural memory
How to do things- actions/skills
No effort to recall
Types Of Long-Term Memory- AO3
- Clinical evidence +
Clive Wearing- episodic impaired due to infection, semantic/procedural unaffected
Different memory stores in LTM - Conflicting neuroimaging evidence -
Buckner+Peterson- location semantic and episodic
Semantic=left side prefrontal cortex
Episodic=right side prefrontal cortex
Tulving- other way around
Poor agreement - Real-world application +
Age=memory loss- specific to episodic
Belleville- intervention- improve episodic in elderly
P’s=better test episodic after training than control
Working Memory Model- AO1
- Baddeley+Hitch- STM
- Central executive=coordinates activities of three sub-systems- limited capacity and does not store info
- Phonological loop=auditory(acoustic) info- divided into phonological store (words you hear) and articulatory process (allows maintenance rehearsal)
Capacity=2 seconds of what can say - Visuo-spatial sketchpad=processes visual and spatial info- divided into visual cache and inner scribe
Capacity=3/4 objects - Episodic buffer=brings together material from other subsystems into single memory- bridge between working memory and LTM
Working Memory Model- AO3
- Clinical evidence +
Shallice+Warrington=KF
poor STM auditory but visual info normal- better when read than read to him
phonological loop damaged but VSS intact
separate visual/acoustic stores - Dual-task performance +
visual and verbal at same time=when tasks separate
when both tasks same=performance declined- competing for same subsystem - Nature of central executive -
Baddeley=central executive most important but least understood- needs better specification than attention
challenges integrity WMM
Explanations for Forgetting- Interference- AO1
- Interference=forgetting as one memory blocks another, causing forget/distortion
- Proactive=when old memory interferes with new
- Retroactive=when new memory interferes with old
- McGeoch+McDonald=RI changing similarity between sets of materials- 10 words accurate then new list
Synonyms/antonyms/unrelated/consonant syllables/3-digit numbers/no new list
Synonyms=worst recall - Similarity affecting recall=PI(new info difficult to store)or RI(new info overwrites similar memories)
Explanations for Forgetting- Interference- AO3
- Real-world interference +
Baddeley+Hitch=rugby players recall team names played against
players who player more games=poorest recall
increase validity - Interference and cues -
Tulving+Psotka=lists of words organised into categories
70% recall first list but progressively worse
given cue=70% recall
interference=temporary loss accessibility - Support from drug studies +
Coenen+Luijtelaar=list of words with diazepam=recall one week later was poorer than placebo
list learned before drug taken=recall better than placebo
drug improved recall beforehand
cannot retroactively interfere
Explanations for Forgetting- Retrieval Failure
- Retrieval failure=when don’t have necessary cues to access memory
- Encoding specificity principle- Tulving=if cue is helpful, needs to be present at encoding and retrieval
- Context-dependent forgetting=external cue
Godden+Baddeley=deep sea divers
learn+recall land/learn+recall sea/learn sea recall land/learn land recall sea
recall=40% lower in non-matched conditions - State-dependent forgetting=internal cue
Carter+Cassaday=antihistamine(drowsy)
learn+recall drug/learn+recall no drug/learn drug recall no/learn no recall drug
when mismatch, recall worse
Explanations for Forgetting- Retrieval Failure- AO3
- Real-world application +
Baddeley=cues worth paying attention to
when trouble remembering something, worth making effort to recall environment in which learned it first - Research support +
Godden+Baddeley and Carter+Cassaday=lack of cues=context and state dependent forgetting
Eyesenck+Keane=retrieval failure main reason forgetting from LTM - Recall vs recognition -
Godden+Baddeley=replicated experiment but used recognition test instead of recall
no context-dependent effect- performance same in all conditions
Factors Affecting the Accuracy of Eyewitness Testimony: Misleading Information- AO1
- Leading questions=Loftus+Palmer=45 p’s watched video of car accident and asked how fast going when hit each other- verb was changed
mean speed- contacted=31.8mph
mean speed- smashed=40.5mph - Why
Response-bias explanation=wording has no impact on memory, but changes how question answered
Substitution explanation=wording changes p’s memory- smashed also saw broken glass - Post-event discussion=Gabbert=p’s saw video of crime from different pov’s and discussed before recall test
71% p’s recalled aspects they did not see - Why
Memory contamination=combining info from other witnesses with own memories
Memory conformity=memory unchanged but going along with others as think they’re right or social approval (ISI/NSI)
Factors Affecting the Accuracy of Eyewitness Testimony: Misleading Information- AO3
- Real-world application +
Loftus=police need to be careful in wording questions as leading has great distortion on memory
Psychologists=expert witnesses in court/explain limits of EWT to juries - Evidence against substitution -
Sutherland+Hayne=p’s video clip and asked misleading questions
Recall more accurate for central details than peripheral ones=memories resistant to misleading info - Evidence challenging memory conformity -
Skagerberg+Wright=two versions of clip where one dark hair/other light hair and discussed
reported a blend of the two versions
Factors Affecting the Accuracy of Eyewitness Testimony: Anxiety- AO1
- Anxiety=state of emotional and physical arousal
- Anxiety has negative effect on recall (weapon focus)
Johnson+Scott=deceived that lab study- low anxiety=overheard convo, man left holding pen and grease on hands- high anxiety=heated argument/breaking glass, man left holding knife covered in blood
Picked man out of 50 photos=49% low anxiety correct, 33% high anxiety - Anxiety has a positive effect on recall
Yuille+Cutshall=real shooting in gun shop- interviews five months after compared to those at incident- stress on 7-point scale and emotional problems
Little change in recall-high stress=most accurate(88% compared to 75%) - Explaining the contradictory findings
Yerkes-Dodson=inverted-U
Deffenbacher-lower levels anxiety/arousal=lower recall
Optimum anxiety where maximum accuracy
Factors Affecting the Accuracy of Eyewitness Testimony: Anxiety- AO3
- Unusualness not anxiety -
Pickel=scissors/handgun/wallet/raw chicken in hair salon
recall poorer in high unusualness conditions
weapon focus due to unusualness not anxiety - Support for negative effects +
Valentine+Mesout=weapon focus leads to negative recall
heart-rate divided high and low anxiety groups
higher anxiety disrupted recall of actor in London dungeons - Support for positive effects +
Christianson+Hubinette=58 witnesses actual bank robberies- some directly(high anxiety)/indirectly(low anxiety) involved
recall=<75% accurate for everyone but direct victims even more accurate
Improving the Accuracy of Eyewitness Testimony- Cognitive Interview- AO1
- Report everything
every single detail even if seems irrelevant - Reinstate the context
witness return to original crime scene in mind to imagine environment and emotions (context-dependent forgetting) - Reverse the order
events recalled in different sequence to how occurred- prevents reporting expectations and dishonesty - Change perspective
recall incident from other people’s perspectives- disrupt expectations and effect schema on recall - Enhanced cognitive interview=Fisher- focus on social interactions
Eye-contact / open-ended questions / minimising distractions
Improving the Accuracy of Eyewitness Testimony- Cognitive Interview- AO3
- Support for effectiveness of CI +
Kohnken=meta-analysis compared CI with standard police interview
CI=41% increase on accurate info- few studies showed no difference - Some elements may be more useful -
Milne+Bull=four techniques alone=more info than standard police interview
Combo of report everything and reinstate context=best recall
some aspects more useful than others