COGNITIVE - Memory - Studies Flashcards
Which study looked at the duration of the STM?
Peterson & Peterson
Peterson & Peterson: Method
- Patricipants shown nonsense trigrams
- Asked to recall them after 3,6,9,12,15 or 18 seconds
- During the pause they had to count backwards in threes (interference task)
Peterson & Peterson: Results
After 3 seconds participants could recall about 80% of trigrams correctly
After 18 seconds participants could recall 10% correctly
Peterson & Peterson: Conclusion
When rehearsal is prevented very little can stay in the STM
Peterson & Peterson: Evaluation
- Reliable as it was a lab experiment enables variables to be tightly controlled
- Lacks ecological validity
- Only one type of stimulus was used
- Each participant saw many different trigrams which means the first test might be the only realistic one.
Which study explored very long term memories?
Bahrick et al
Bahrick et al: Method
-392 people asked to recall ex-classmates (free call test). –They were then shown photos and asked to recall thier names (photo recognition test) or given names to match to photos (name-recognition test)
Bahrick et al: Results
Within 15 years of leaving school people would recognise about 90% of names and faces. 60% on free recall test
Within 30 years of leaving school free recall declined to 30%
After 48 years name recognition was 80% accurate and photo recognition 40% accurate.
Bahrick et al: Conclusion
Evidence of VLTM in a ‘real life’ way.
Recognition is better that recall suggesting a huge store of information that is not always easy access.
Bahrick et al: Evaluation
- High ecological validity as it was a field experiment
- Cannot control variables, no way of knowing why information was recalled well
- This type of information can be rehearsed well
- Because of this the results cannot be generalised to other types of info held in the LTM
Which study looked into the capacity of the STM?
Jacobs
Jacobs: Method
- Participants presented with a string of letters or digits.
- They had to repeat them back in the same order until they failed to recall correctly
Jacobs: Results
- Participants recalled around 9 digits and about 7 letters
- Capacity increased with age during childhoods
Jacobs: Conclusion
- STM has a limited capacity of 5-9 items.
- Individual differenced: STM increased with age
- People may use memory techniques such as chunking, making recall easier
Jacobs: Evaluation
- lacks ecological validity as it is an artificial task
- more meaningful information may be recalled better
- previous sequences may have confused the participant
Which study investigated encoding in both the LTM and STM
Baddeley et al
Baddeley et al: Method
- Participants given four sets of words that were wither acoustically similar and different or semantically similar and different
- Using an independent groups design participants had to recall words immediately or 20 minutes later after a task
Baddeley et al: Results
- Participants had problems recalling acoustically similar words immediately from STM
- Recalling from LTM they had problems recalling semantically similar words.
Baddeley et al: Conclusion
Confusion between similar words suggest that the LTM stores semantically and the STM stores acoustically
Baddeley et al: Evaluation
- Lacks ecological validity
- Other methods of encoding that the study does not include
- No control over participant variables
Loftus & Palmer: Method
- Shown a film of a multiple car crash
- Then asked question on the crash
- '’how fast do you think the cars were going when they hit?’’
- In different conditions the word hit was replaced with ‘‘smashed’’ ‘‘collided’’ ‘‘bumped’’ or ‘‘contacted’’
Loftus & Palmer: Results
When the adjective used was more violent a faster speed estimate was given. (average 41 mph) the less violent adjective averages 32 mph
Loftus & Palmer: Conclusion
Leading questions affect the accuracy of people’s memories of events.
Loftus & Palmer: Evaluation
- Artificial did not reflect a real life event.
- May have been effected by demand characteristics. Lowering the validity and reliability
Who conducted research and found the ‘‘serial position effect’’?
Glanzer & Cunitz
What conclusions can be made from Glanzer & Cunitz serial position curve?
With immediate recall the first and last items on a list are recalled well. Retrieval depends on position of word in series
Recency effect shows STM
Primacy effect shows LTM
Where STM capacity is overloaded info was displaced
Which studies disprooves the idea in the MSM that rehearsal is the primary process for transferring info into the LTM?
Craick & Lockhart
Craik & Tulving
What did Cracik & Lockhart find?
Transfer to the LTM relies not on how much repetition/rehearsal but how meaningful the info is.
What did Craik & Tulving find?
Participants recalled more words when the had been processed semantically rather than in a superficial way.
Which study indicates that the STM has a visual store?
Baddeley et al 1973
Baddeley et al 1973: Results
Participants were unable to perform two visual task simultaneously
Performance in tasks was not impaired by doing verbal repetition task
Baddeley et al 1973: Implications of results
STM has a visual store
STM is comprised of several sub systems
Visuo-spatial sketchpad and phonological loop are seperate
Visuo-spatial sketchpad has a limited capacity
Loftus 1979: Method
- Participants wait outside lab
- They experience one of two conditions: Low discussion in lab about broken machine, man leaves holding a pen in grease covered hands OR Loud argument with sounds of crashing and glass smashing. Man leaves room holding a pen in blood covered hands
- Participants then asked to identify him from 50 faces
Loftus 1979: Results
Pen condition: 49% correctly identified face
Knife condition: 33% correctly identified face
Loftus 1979: Conclusion
Attention is drawn to the weapon, distracting from the appearance of the perpetrator.
Loftus 1979: Evaluation
Supporting evidence from Loftus and Messot
Loftus & Messot: Method
Independant groups shown one of two series of pictures;
1)Customer pointing gun at a cashier
2)Cutomer handing cashier a cheque
Eye movement was recorded
Loftus & Messot: Results
More eye fixation on weapon than cheque
Fixation on weapon was of longer duration that fixation on cheque
Memory in weapon condition poorer than cheque condition
Which study contradicts what was found by Loftus 1979 and Loftus & Messot?
Christianson & Hubinette
Christianson & Hubinette: Method
Interviewed eyewitnesses of real crimes about everything they saw.
Christianson & Hubinette: Results
Those who had actually been threatened were more accurate in their recall. For example they could remember more about the appearance of the attacker.
Christianson & Hubinette: Evaluation
-Higher validity that Loftus’ studies as it is real life evidence.
Loftus & Zanni: Method
Lab experiment using independant groups design
Participants watched a short film
One group was asked an open question ‘did you see a broken headlight’ other group asked ‘did you see the broken headlight’ - misleading question
There was not a broken headlight in the film.
Loftus & Zanni: Results
Misleading question: 17% remembered seeing a broken headlight
Open question: 7% recalled a headlight
Loftus & Zanni: Conclusion
Wording of a question impacts memory of an event by seeming to distort it
Loftus & Zanni: Evaluation
- Lab experiment lacks ecological validity
- May simply demonstrate demand characteristics
- Controlled lab experiment isolates causal link between question asked and memory recalled
Which study suggests young children as eyewitnesses have poorer recall
Flin et al
Flin et al: Method
Staged an incident in front of a sample of children and adults
They were asked questions about it 1 day later and 5 months later
Flin et al: Results
Both groups (young and old) performed equally well the following day but after five months the children’s group had forgotten significantly more
Flin et al: Conclusion
the EWT of children becomes less reliable over time
Flin et al: Evaluation
practical implications for children being questioned as soon as possible after an event.
-Naturalistic experiment therefore high ecological validity
Memon et al: Method
Restaged Flin et al’s study but with two older age groups (6-33) and (60 to 82)
Memon et al: Results
Questioned 35 minutes after event: age had little effect on accuracy of recall
a week later: older age group had declined significantly in their accuracy.
Memon et al: Conclusion
As age increases the accuracy of recall decreases
Yarmey: Method
651 participants were stopped by a woman and talked to for 15 seconds
Two minutes later participants stopped again and asked to recall physical characteristics of the woman.
Yarmey: Results
All age groups performed similarly however, younger age groups were more confident in their recall.
Yarmey: Conclusion
Little difference in accuracy of age-related recall but a difference in confidence of recall.
Yarmey: Evaluation
- Large sample, however opportunity sampling was used therefore the sample could be biased
- Natural setting increases ecological validity
- Less control over extraneous variables
Which study suggests that children’s lack of schemas effect their encoding of a memory?
Ceci & Bruck
Ceci & Bruck: Conclusion
Lack of schema makes it harder for children to encode certain events.
However, adults’ schemas can cause them to ‘see’ things that are not there.
Leichman & Ceci: Conclusion
Children are more suggestible.
3-6 year old children were given repeated misleading information in questions they will eventually incorporate it into their memory.
Cohen & Faulkner: Conclusion
Elderly people are more susceptible to the effects of misleading info than middle aged people.
Memon: Method
Replicated Flin et al’s study but with two older age groups (6-33) and (60 to 82).
They were then questioned about the incident 35 minutes later and 1 week later.
Memon: Results
35 minutes after event: age had little effect on accuracy of recall.
a week later: the older age group had declined significantly in their accuracy.
Memon: Conclusion
Age impacts accuracy of recall after longer time periods.
Clarke-Stewart et al (2-3 year olds): Method
Series of separate observations of peer relations between children from different social backgrounds
Clarke-Stewart et al (18 month olds): Method
To look at strength of attachment
Put a group of children who were in intensive hours of daycare (30 hours at least) in the strange situation
Compared results with children in low intensity hours of day care ( less than 10 hours a week) who has also been placed in the strange situation
Clarke-Stewart et al (2-3 year olds): Results
Those who had experienced day care were better at negotiating and coping in social situations
Clarke-Stewart et al (18 month olds): Results
Those who had high intensity hours of day care were just as distress when separated from their mother’s as those who were in low intensity hours of day care
Clarke-Stewart et al (2-3 year olds): Conclusion
Day care has a positive impact on 2-3 year olds
Clarke-Stewart et al (18 month olds): Conclusions
Attachments in 18 month old are not affected by temporary separation
Clarke-Stewart et al (2-3 year olds): Evaluation
Controlled so study can be easily replicated
Artificial situation so lacks ecological validity
Clarke-Stewart et al (18 month olds): Evaluation
Controlled so study can be easily replicated
Artificial situation so lacks ecological validity
Only tested on infants in day care, not compared to children who experience no day care at all
Shea
3-4 year oldsobserved via video tape of them playing in play ground
Their behavior was assessed in terms of rough and tumble play, distance from teacher and distance from nearest child
Shea: Results
Over 10 weeks the peer interaction increased and distance from teacher decreased
Decrease in aggression and increase in rough and tumble play
Increase in sociability was more notable in children who attended day care 5 days a week than children who attended day care twice a week
Shea: Conclusion
Day care causes children to be more sociable and less aggressive
Shea: Evaluation
High ecological validity as a result of a naturalistic observation
Results may be affected by extraneous variable
Behaviour was open to interpretation so findings may be biased
Belksy & Rovine: Method
Infants placed in the strange situation
One group experienced no day care and the other had experienced at least 20 hours a week before their first birthday
Belksy & Rovine: Results
Day care: More likely to be insecurely attached, either Type A or Type C
No day care: More likely to be securely attached Type B
Belksy & Rovine: Conclusion
Day care has a negative effect on a child’s social development
Belksy & Rovine: Evaluation
Good control over variables as it is a controlled observation
Lacks ecological validity
DiLalla supports this: The more time in day the less prosocial the child behaved
