Memory

MEMORY

THE MULTI STORE MODEL

Considerable evidence of different stores Clive Wearing- STM but no new LTM, but can recall some LTM Glanzer & Cunitz- primacy and recency effect

Bekerian and Baddeley- people didn’t notice a change in radio wavelength (e.g. 95.8 changed to 96.7) despite rehearsal of seeing/hearing it regularly

Over-simplified- assumes a single STM and LTM, but it is proven that there are different stores within both STM and LTM

SHORT TERM MEMORY• Capacity

– Baddeley- 5 words; set of one-syllable words and set of multi-syllable words– Whatever can be articulated in 2 seconds, more short words recalled than long

words– Miller 1956- people have a digit span of 7+/- 2

• Duration– Peterson & Peterson 1959- shown trigrams then asked to count backwards to

prevent rehearsal– 80% of trigrams were recalled after 3 seconds, but less than 10% after 18 seconds

• Encoding– Baddeley 1966- participants in four groups; acoustically similar, acoustically

dissimilar, semantically similar, semantically dissimilar– 55% of acoustically similar words recalled, 75% of acoustically dissimilar words

recalled– Semantics did not affect the results that much

LONG TERM MEMORY• Capacity- potentially unlimited• Duration

– Bahrick 1975- 392 graduates shown yearbook photos after 47 years– One group recalled names from memory (recall) and other matched names to

faces (recognition)– Recall group had less than 20% accuracy– Recognition group had 60% accuracy

• Encoding– Baddeley 1966- participants in four groups; acoustically similar, acoustically

dissimilar, semantically similar, semantically dissimilar– After 20 minutes they were given another task before recalling words– 55% accuracy for semantically similar words, and 85% accuracy for semantically

dissimilar words– Acoustics did not affect the results that much

THE WORKING MEMORY MODEL Farah- patient was good at spatial

tasks but not ones involving visual imagery

Word length effect- short words recalled better than long words, supporting articulatory loop having limited time-based capacity

If we do two tasks simultaneously that need the same systems, we struggle

Not enough research into central executive, which is the most important component

Not clear how working memory and LTM work together

ANXIETY & EYE WITNESS TESTIMONY

• Effect- narrows focus of attention so recall is better, but too much anxiety can have negative effects on EWT

• Research– Christianson & Hubinette- 110 bank robbery witnesses– Victims of the crime had more accurate recall and bystanders had less

accurate recall– Loftus 1979- participants heard a discussion in a nearby room– Condition 1- man enters with a pen and grease on hands– Condition 2- man enters with knife covered in blood– 49% of condition 1 were accurate in identifying the face from 50 photos, but

only 33% from condition 2 were accurate, disproving Christianson & Hubinette but supporting the fact that too much anxiety causes inaccurate recall

SCHEMAS & EYE WITNESS TESTIMONY

• Effect– Low schema expectancy = ignored– False information remembered (high schema expectancy)

• Research– Brewer & Treyens 1981- 30 people wait in office for 35 seconds– Unexpected recall test- 61 items (some typical office items,

some random/incompatible items)– People remembered typical items with high schema

expectancy, and recalled false items due to a high expectancy

AGE & EYE WITNESS TESTIMONY

• Effect- children are inferior to adults because they lack schemas, have inferior capability, and memory capacity increases with age

• Research– Ceci & Bruck 1993– Leading questions confuse children– Preschool children provide relevant eye witness

testimony

MISLEADING INFORMATION & EYE WITNESS TESTIMONY

• Effect– Words used/leading questions- influence answers– Information given after the event in leading questions may

replace the actual information• Research– Loftus 1975- group shown car accident film and asked

questions using different words for each individual group e.g. ‘smashed’, ‘bumped’

– People stated that the speed of the car before the crash was much faster in the ‘smashed’ group than in the ‘bumped’ group

THE COGNITIVE INTERVIEW

• Context reinstatement- does not involve revisiting the scene of the crime, but to recall wider scenes; the weather, your thoughts/feelings, preceding events

• Report everything- recall every detail, even if the relevance is questionable

• Recall from changed perspective- attempt to describe the incident from the perspective of someone else at the scene

• Recall in reverse order- report incident in reverse order

MEMORY IMPROVEMENT

• The role of attention– Ericsson & Chase- person who could memorise up to 80 things (2 year

practice- 1 hour a day) proves that rehearsal and attention improve memory (multi-store)

• Elaborative rehearsal– Craik & Watkins– Maintenance rehearsal; repeat information, only stays in STM for a few

seconds– Elaborate; needed to transfer to LTM, link to previous knowledge, easier to

recall because there are several paths to reach it• Encoding

– Tulving & Osler- two weakly linked words; recall vs. recognition– Recognition- greater overlap with the information originally encoded

MEMORY IMPROVEMENT

• Organisation– Bower- list of words, either randomly or in a hierarchy– Organised group- 65% correctly remembered– Control group- 19% correctly remembered– Bower & Clark- either random or presented in a story– Organised group- over 90% correctly remembered– Control group- 10% correctly remembered

• Mnemonics– Effective retrieval cues– Method of loci- associate with places– Peg-word- one=bun, two=shoe, etc. associate words with these– Bellezza- peg-words are more flexible and effective than method of loci