Atkinson and Shiffrin
- Created Multi-store model.
Sensory store (store for every sense) - Short term (unitary) - Long-term (unitary) with rehearsal and attention included.
- Passes through stores in a fixed sequence.
- Information can be lost at any stage of teh sequence.
- Usually recoded when going through stores.
- If no attention is given information decays.
- Information can only go through short and long term with rehearsal, if not rehearsed it will decay.
- Each store has a different duration, encoding and capacity.
Peterson and Peterson
- Participants look at nonsense trigram briefly, count backwards from given number in 3's or 4's (preventing rehearsal). Each trial interval changed between 3-18 seconds and recalled.
- Short term has small duration when rehearsal prevented. Could recall 80% of trigrams after 3 seconds but only 10% after 18 seconds. Proving duration is 20 seconds max.
- Based on artificial stimuli.
- Counting backwards, rather than preventing rehearsal may have displaced trigram.
- Repeated measures design, order effects. Acuracy got worse as test went on.
- Nonsense and a three letter word makes recall differ as word can be recalled easier.
- Showed random sequence of 6 consonants briefly on screen. 1) similar sounding 2) different sounding. Then had to write down cosonants in order.
- Short term used acoustic encoding mainly. Found more difficult, more errors with similar sounding consonants.
- Uses artificial stimuli. Used university students, not representative. Consonants only represented in acoustic and visual.
- Baddeley carried out similar study using words supporting Conrad.
- Digit span technique. Given string of unrelated digits increasing digit at a time. Measured by where participant can no longer recall sequence.
- Short term capacity limited.
- Digit span, articificial technique. Hard to eliminate influence of long term.
- Baddeley, and others, found short term holds however much we can say in 2 seconds.
- Made article about 7+-2.
- Span can be increased by chunking.
- No independant measure of a 'chunk'/vague. Depends on number of items in chunk and anxiety of participants.
- 400 Amerian high-school grads on memory of schoolmates.
- Used variety of memory tests, recognition of photos, recalling names and recalling names without photo cue.
- Performed well up to 34 after left school. Better on recognition tasks than recall. Performance declined after 47 years.
- Looks at real life situation, good mundane realism. Difficult controlling extraneous variables. Sometimes need retrieval cues for long term. Later research shows info lasts longer if well processed and if material is is understood.
- Lists of words 1)sound similar 2)not sound similar 3)mean the same 4)dont mean the same
- Presented 10 words from each list, prevented rehearsal then asked to recall after 20 minutes.
- Performed less well with the similar meaning lists. Concluded this was because long term codes mainly semantically.
- Study uses real words but carried in laboratory reducing validity. Instantly recognised sounds show acoustic enconding in long term and other research show semantic is main form however visual encoding is used also.
HM, Clive Wearing, KF
- HM and Clive Wearing: short term functioned well however the transfer and retrieval from long term is impossible.
- KF: Intact long term but a impaired short term.
Supporting Unitary stores (muti-store model)
However KF goes against multi-store:
- KF: Could put new information into long term even when short term wasn't working meaning there must be another pathway to the long term memory. He also put long term memories without processing it through short term, disproving the theory of a fixed pathway through the stores.
Baddeley and Hitch
- Created Working Memory Model.
Central executive (controls slave systems and limited capacity) - Phonological loop (Phonological store, inner ear holding spoken information and limited capacity. Articulatory loop, inner voice repeats phonological store info recoding written info to articulatory code) - Visuo spatial sketchpad (Visual cache, inner eye storing visual and spatial info and limited capacity. Inner scribe, rehearsal mechanism for visuo-spatial information)
- Explains short term memory which is not unitary.
- Each component has particular function, purpose.
- Central executive is key component overseeing, co-ordinating slaves.
- 2 way flow between central executive and slaves.
- Slaves are independant and have seperate responsibilities.
- Modified over the years taking account of new research, new components added (episodic buffer)
Gave participants dual task, reasoning and reading aloud. Should do both very well showing different components in short term.
Baddeley ET AL.
- Gave brief visual presentations of lists of words, short or long, asked to recall list immediatley in order.
- Participants recall more short words than long (word length effect).
- Showing loop holds info said from 1.5-2 seconds . Loop has time limit not item limit.
- Gave dual task, tracking list and visual imagery task.
- Participants poorer at dual task than when performed alone.
- Both tasks in visuo-spatial sketchpad meaning it were competing with samel limited resources.
- Participants sit outside lab, thought listening to fight between people inside. 1) Overheard friendly conversation, with man coming out with greasy hands and a pen. 2) Fight heard furniture overturned, man came out with bloodstained knife. Identify man from 50 photos.
- Participants witnessed violence less accurate. Concluded because of heightened arousal (anxiety) making then focus on weapon not man.
- Staged, some mundane realism because of deception. Ethically exposed to anxiety.
- Showed film of events leading up to car accident. 1)questions consistent with film 2) same apart from 'barn' question
- Recalling film, 17% misled reported barn, 3% in consistent group.
- Misled group incorporated false information about barn in original memory. Result is significant, not all were affected.
Christianson and Hubinette
- Surveyed 110 peopl, witnessed around 22 bank robberies as direct or bystander victims.
- Victims subject to highest anxiety had more accurate, detailed recall than bystanders.
- Suggests people react differently to anxiety-inducing events in real life.
Flin ET AL.
- Children and adults questioned about incident witnessed, one day after and 5 months after.
- Recall similar after 1 day but after 5 months worse recall from children.
- Declien in accuracy shows time is important when dealing with children court appearances.
Gordon ET AL.
- Reviewed studies on child witnesses.
- Children can recall accuratley in detail but more susceptable to misleading information.
- Young and elderly film of staged event, asked questions about film.
- 80% elderly failed to mention key detail (attacker, knife in hand), 20% young adults.
- Artificial situation, might not reflect how people act in real-life.
- Davies, disputed this thinking children resist misleadin information when sensitivly questioned.
Loftus and Palmer
- Showed film car accident then asked questions about it. Crucial question (speed of the car when they 'collided, smashed, contacted...')
- 'Smashed' gave highest estimated speed, 'Contacted' gave lowest estimate. Week later 'Smashed' more likely to say they saw broken glass.
- Verb has significant effect on speed estimate, continued to have effect after week delay. Suggests false memory permanently lodged in memory.
- Critics say might have responded to demand characteristics.
Fisher ET AL.
Genuine interviews by experienced police in Florida:
- questions brief,direct,closed.
- sequencing questions didn't match witnesses image of event.
- police often interrupted, witnesses didn't expand on answers.
- Added features making enhanced cognitive technique - minimal distractions,active listening,ask open-end questions,pause after every response,avoid interruption,adapt use of language suiting witness avoiding judgmental comments.
- Trained detectives,enhanced cognitive interview.
- Found cognitive increased amount of information compared to standard.
- Used real police officers and crime witnesses, mundane realism.
Geiselman ET AL.
Made Cognitive Interview:
- Report everything, report everythin even the unnecessary information e.g. weather as may trigger memory of something else.
- Recall from changed perspective: Put yourself in someone else shoes, from their point of view.
- Recall in reverse order: Recall details back to front or from a certain point and onwards or backwards from that.
- Context reinstatement: Put yourseld back into scene. Tell your feelings, what were you doing before event, why were you there, weather, who was standing around etc..
Showed videos of stimulated crime. Tested recall on cognitive, standard,hypnosis. Cognitive prompted most information.
Milne and Bull
- Tested coginitive techniques by themselves and grouped.
- 4 techniques alone produced more information than standard. Cognitive reinstatement and Recall everything together gave best response.
- Confirmed UK police's thoughts, some techniques are better than others.
Koehnken ET AL.
- Found cognitive interview gave more incorrect information than the standard interview.
Gruneberg and Jacobs
- Keyword method is very effective when learning foreign words.
Loftus and Christianson
- Supported Loftus staged study.
- People interviewed 6 months after seen traumatic filmed event, remembered essence well but impaired memory of details surrounding it.