2. Multi Store Model - Atkinson &
Shiffrin
Environmental Input
Sensory Input
(sights, sounds, etc.)
Sensory
Memory
Forgotten
Short Term
Memory
Long Term
Memory
Forgotten
Through
Decay or
Displacement
Forgotten
Through
Interference
or Retrieval
Failure
Maintenance
Attention
Elaborate
Rehearsal
Leads to
Storage
Rehearsal
Retrieval
3. Multi Store Model – Atkinson and
Shiffrin
• Information received through the senses is stored in the
sensory memory
• A small selection of the information is selected for further
processing in the short term memory
– If it is not selected, it is simply forgotten
• Information is actively processed through rehearsal to
maintain it
– If it is not maintained or goes through elaborate rehearsal, it will
be forgotten through decay or displacement
• If it is maintained properly through elaborate rehearsal, it
transfers into the long term memory for permanent
storage
– It can only be forgotten here through interference or retrieval
failure
4. Multi Store Model – Atkinson and
Shiffrin
• Positive
– Influential/useful
• Was an influential early model that psychologists still use today
– STM/LTM differences
• Considerable evidence that there are distinct types of memory store
– Evidence
• The serial position effect
– Primacy effect where the words you hear first so have been rehearsed
and can be recalled from LTM
– Recency effect where the words you hear last can be recalled from
STM as they are still present
– Clinical case studies
• K.F. had very poor STM due to a motorbike accident but LTM for
memories after accident was normal
5. Multi Store Model – Atkinson and
Shiffrin
• Negative
– Just rehearsal doesn’t ensure transfer from STM to LTM
• Bekerian & Baddeley
– Found people didn’t know about changes to BBC radio despite hearing
information (on average) over 1000 times
» Suggests rehearsal is not the only factor in moving information from STM to
LTM
– Over-emphasis on one way direction of MSM
• There is a two way flow of information between STM and LTM
• Morris
– Demonstrated how previous knowledge and interest in a topic can help in the
recall of fictitious information based on the topic
– Over-simplified
• Assumes a single STM and LTM store and it has been demonstrated that
there are different types of STM and LTM
– Over-emphasis on the amount of information
• Cohen
– Memory capacity cannot be measured purely on what can be recalled but the
nature of the information
– Some things are easier to recall than others and MSM does not take it into
account
6. Working Memory Model – Baddeley
and Hitch
Sensory
Memory
Episodic Buffer
Central
Executive
Phonological
Loop
Visuo-Spatial
Sketchpad
Language Visual SemanticsEpisodic LTM
Long Term Memory
7. • Central executive
– An additional process to monitor incoming data and allocates “slave
systems” to tasks
• Limitations
– Vaguely defined and doesn’t really explain anything
– May possibly consist of many stores
• Phonological loop
– Auditory information and preserves order
– Phonological store
• Stores words you hear
– Articulatory process
• Allows maintenance rehearsal (repeating words)
– Evidence
• Participants asked to perform 2 tasks simultaneously which use the same
system, performance is effected
– Reading whilst speaking both use this so it can’t cope due to its limited capacity
Working Memory Model – Baddeley
and Hitch
8. Working Memory Model – Baddeley
and Hitch
• Visuo-spatial sketchpad
– Temporary store of visual and spatial information
– Visual cache
• Stores information
– Inner scribe
• Spatial relations
– Baddeley
• Lab experiment
• Participants had more difficulty doing 2 visual tasks simultaneously
compared to a visual and verbal task
– Tracking a light and describing the shape of the letter F
• Episodic buffer
– Links information across domains form integrated units of visual, spatial
and verbal information
– Encodes to LTM
9. Working Memory Model – Baddeley
and Hitch
• Weaknesses
– Vagueness of the central executive
• The one we know least about
• Richardson
– Problems in specifying the precise functioning of the central executive
• General evaluation
– All of the techniques used in MSM and WMM are lab based
– All have problems associated with the controlled laboratory environment
10. Short Term Memory
• Capacity
– Limited (Miller’s “magic number) 7+/- 2
– Jacobs
• Participants read words or numbers and had to recall immediately after presentation
(recall had to be in the correct order)
• Found that participants could remember 9 numbers or 7 letters and recall increased
with age
• Duration
– Limited
– Some say seconds unless it is rehearsed
– Peterson & Peterson
• Students recalled combinations of 3 letters over increasing intervals
• During intervals, students were prevented from rehearsing by a counting task
• Findings suggest STM fades in under half a minute without rehearsal
• 3 seconds = 80% recall, 18 seconds = 10% recall
• Encoding
– Acoustically (by sound)
– Conrad
• Visually presented student letters one at a time
• Found letters which are acoustically similar were harder to recall than acoustically
dissimilar
• Suggests STM codes acoustically despite being represented visually
11. Long Term Memory
• Capacity
– Potentially unlimited
• Duration
– Anything up to a lifetime (minutes to years)
– Bahrick
• Tested US graduates
• Shown classmates photos years later
• 90% accuracy for remembering faces and names 34 years after graduation
• Declined after 48 years, especially for faces
• Encoding
– Semantically (by meaning)
– Baddeley
• Presented a list of 10 short words, some semantically similar others not
• Tested immediately and then again 20 minutes after
• Found after 20 minutes, recall of semantically similar words was poor
• Suggests we encode by what words mean so semantically similar words are confused
12. Eye-Witness Testimony – Anxiety
and EWT
• Anxiety
– Deffenbacher
• Reviewed 21 studies and hypothesised that anxiety-performance relationship is an
inverted U shape proposed by the Yerkes-Dodson law
– For tasks of moderate complexity, performance improves with an increase of anxiety up to an
optimal point at which it starts to decline
– Loftus
• Lab experiment
• Participants heard a heated discussion in adjoining room
– Condition 1
» Man exited with pen and greasy hands
– Condition 2
» Man exited with paperknife and bloody hands
• Found participants were more focused on a weapon than on the face of a person
• When asked to recall, condition 1 were 49% accurate and condition 2 were 33%
accurate
– Weapon distracted witness from person holding it
• Backs the assertion that anxiety diverts the attention from important features, such as
faces
13. Eye-Witness Testimony – Anxiety
and EWT
• Anxiety
– Evaluation
• Over-simplistic
– Deffenbacher reviewed earlier findings due to being over-simplistic
– Instead based assumption on 63 studies
– Now suggests EWT performance increases gradually up to extremely high levels and the has
a catastrophic drop
– Yuille and Cutshall
• Accuracy of testimony in real-life situations
• Interviewed 13 witnesses for real-life shooting
– Some saw it close up others from a distance
– Witnesses gave impressively accurate accounts after several months
– Closer to the shooting = more detailed account
– Misleading questions had no effect
– Most distressed = most accurate after 5 months
• Suggests heightened arousal associated with anxiety enhanced accuracy of recall
– Christianson and Hubinette
• Questioned 110 witnesses who had a total of 22 genuine bank robberies between them
– Some were onlookers others were directly threatened
• Found that victims were more accurate and detailed in recall compared to bystanders
• Superior recall apparent even after 15 month interval
• Concluded that people (especially victims) are good at remembering highly stressful
situations in real-life compared to in a laboratory environment
14. Eye-Witness Testimony – Anxiety
and EWT
• Schemas
– Mental template
• A knowledge structure that relate to commonly encountered objects, situations or
people
• Used to interpret and process information
• Enable us to predict events, make sense of unfamiliar circumstances, organise
behaviour
• Act as filters to perception and recall
– Brewer and Treyens
• Effects of schemas on visual memory
• 30 participants left in a room for 35 seconds
• Room planned like an office with objects both relating to an office environment and
objects which don’t
• Participants given unexpected recall test
• Found that typical office objects were more likely to be recalled
– Participants made substitutions for objects normally expected
– Falsely recalled where objects were placed
– Schema influenced choices made even when inaccurate
– Memory was influenced to what is compatible with their schema, inconsistent information was
filtered out
15. Eye-Witness Testimony – Influencing
Factors• Age differences
– Yarmey
• Field experiment
• 651 adults asked to recall physical description of woman they had spoken to for 15 seconds 2 minutes earlier in a public
place
• Found young (18-29) and middle aged (30-44) were more confident than older (45-65)
• No significant difference in accuracy
• Own-age bias
– Anastasi and Rhodes
• Lab experiment
• 3 different age groups shown 24 photos of all 3 age groups
– 18-25, 35-45, 55-78
• Asked to rate photos on attractiveness
• Short filler task to avoid rehearsal then shown 48 photos
• Recognition rates showed that young and middle aged were more accurate
• All ages were better at recognising own age group
• Age and EWT
– Coxon and Valentine
• Lab experiment
• Focused on misleading information
• 52 children, 53 young adults and 42 elderly people (mean age of 70)
• Watched video of kidnapping and answered questions
– Groups split in half, one half had misleading questions
• Young adults were better when measured by correct answers
• Elderly were less likely to be influenced by misleading questions
– Children
• Hammond and Thole
– Children make less effective witnesses as memories are less efficient and less articulate
– Problem with children’s ability to communicate memories so has implications for how they are questioned
• Warren
– Older children more likely to be influenced by misleading questions compared to adults
16. Eye-Witness Testimony – Misleading
Information (Loftus and Palmer)
• Aim
– Investigate how information provided to a witness after an event will influence
their memory of that event
• Method
– 2 lab experiments
– Independent measures
– IV = verb used
– DV = estimate of speed or whether participants saw glass
• Experiment 1
– 45 students shown short video clip of car crashing
• Split into 5 groups of 9 and asked the same question with different verb
– Asked how fast the cars were going when they (verb) into each other
• Verbs used were: smashed, collided, bumped, hit or contacted
• Results
– How question was phrased influenced speed estimates
• When “smashed” was used estimated speed was much higher (almost 10mph higher)
17. Eye-Witness Testimony – Misleading Information
(Loftus and Palmer)• Experiment 2
– 150 students shown short video clip of multi vehicle car crash
• Split into 3 groups of 50
• Verbs used: hit and smashed, third group not asked about speed
• 1 week later, asked if they had seen glass
• Results
– Smashed group were more likely to say yes (32%, 30% more than control group)
– Show that verb used in original question influenced answer to the second
• Explanations
– Response bias
• Different speed estimates occurred because verb used influences response
– Memory is altered
• Verb changes person’s memory so actually see it differently
– Suggests that a person’s own perception and information supplied after the event both go
into a person’s memory
• Evaluation
– Ecological validity
• Not realistic
• Lab environment
• Shown through video clips
– Can’t generalise to a wider audience
• Only done on students
– Age, driving experience, educational experience
– Not always easy to estimate speed
– Type of car may have varied answer
18. Eye-Witness Testimony – Evaluation of
Research
• Demand characteristics
– Been suggested that the participants respond to the experimental situation
• Give answers they feel they are expected to give
– Idea refuted by Loftus
• Gave participants a reward for correct answers and found the same results
• Minor aspects of memory
– Misleading information only affects minor, unimportant aspects of memory
• Participant expectations and consequences
– Participants don’t expect to be mislead by a researcher
– Consequence of inaccurate recall is minimal in lab environment compared to
real-life
– Foster
• Eye witness identification is more accurate for a real-life crime as opposed to in a lab
• Deliberately misleading information
– Memory for important events isn’t easily distorted when information is obviously
misleading
19. The Cognitive Interview – Fisher and
Geiselman
• Positive
– Based on idea of there being several memory retrieval paths
• Information not available through one path may be accessible through another
– Has 4 major characteristics
• Change of narrative order
– Try to recount the scene in a different chronological order
• Change of perspective
– Try to recount the scene from a different perspective
• Mental reinstatement of context
– Try to return to the environment and emotional context of the event
• Report everything
– Recall the maximum amount of information even if it is believed to be unimportant
– Evaluation
• Godden and Baddeley have research to support the idea
– Research showed that an increase in the amount recalled using the cognitive interview
• The cognitive interview has been improved
– now attempts to create a better rapport between the interviewer and interviewee
• Geiselman tested the validity of the cognitive interview
– Found it compared favourably to the standard interview
• Negative
– Practical problems involving the application of the cognitive interview
• Memon
– Failed to find an improvement when using a cognitive interview technique when used by police officers
– Limited use by the police
• Less frequently used as the “change of perspective” is believed to lead witnesses to speculate
20. Memory Strategies
• Chunking
– Capacity of STM can be increased if information is grouped together
– Miller
• Capacity of STM is 7+/- 2 chunks rather than individual pieces of information
• Categories
– Deese
• Presented 2 lists of words, one related one not
• More related words recalled
– Tulving and Pearlstone
• The more the material is organised, the easier it is to learn
• Imagery/Method of Loci
– Imagining a visual picture of something
• Walk to school
• Rooms in your house
– Can be easily remembered in sequence
• Interference can occur if used too often
• Mnemonic
– Using rhyme and imagery to remember information
– Has to be learnt by rote
• Can take time and interference between information is common