Loftus and palmer (classic study) Flashcards
What is memory?
A cognitive process which is the ability to retain information then recall it later, which will influence how we behave
Barlett’s theory on memory
Schemas
What are Schemas?
Packets of information which are facts learnt from episodes that occur in our lives.
A mental representation of how the world works which allows us to make sense of it
What is reconstructive memory?
Memory is reconstructed to be coherent and make logical sense to us based on schemas (facts about life we learnt)
How can schemas affect reconstructive memory?
They give us biases and prejudices which cause us to change how we remember specific events
Eg, learnt schema that severe car crashes break glass
So recalls glass being broken when recalling event
Theory loftus came up with
2 types of info that affects memory of an event:
Info gained at the time of an event
Info gained after, affected by language used when questioned about it
Aim of the study
To test with tight controls how language can alter a participants memory of a staged car crash
Experimental design of this study
2 lab experiments both conducted in individual measures
Point of Experiment 1
To see how a verb in a critical question changes participants estimate of speed and how good they are at estimating vehicle speed
Sample used in experiment 1
45 participants divided into 5 groups of 9 dependent on the IV
Dependent variable in experiment 1
The mean speed estimate participants gave after they were asked the critical question ‘at what speed were the cars going when they _ each other?’
Independent variable in experiment 1
The 5 verbs inserted into critical question that determined the condition participants in
What 5 verbs were used in experiment 1 for the critical question?
Contacted, hit, bumper, collided, smashed
Apparatus of experiment 1
7 clips of staged car crashes from Seattle police council
Travelling at speeds of 2 at 40mph, 1 at 30mph, 1at 20mph, 3 had no crashes
Step 1 of experiment 1
Participants watched each clip 1 by 1 then after each immediately after was given a questionnaire to complete
How was the questionnaire organised in procedure 1
Half of paper was to describe what happened in the film
Other had questions to answer including the critical question (if a crash did occur) and if it did it appear, had to guess speed it was travelling at
Step 2 of procedure 1
The mean speeds dependent on the condition (which verb used in critical question) was worked out
How was the data collected in procedure 1?
Self report because it measures a cognitive process that only participants can state themself
Descending order of mean speed estimates for each verb in critical question
Smashed
Collided
Bumped
Hit
Contacted
Mean estimate for speed of ‘smashed’
40.8
Mean estimate for speed of ‘contacted’
31.8
What 2 possible conclusions could be made from procedure 1?
Response bias in asking questions where participants use verb cues to decide how to answer, showing memory wasn’t necessarily changed
Language (verb used) from info gained after event can actually falsely reconstruct memory
Why was procedure 2 conducted?
Because inferential analysis showed difference in estimates of speed between smashed or contacted was significant
And to see which conclusion is correct
What was the aim behind procedure 2
If participants memory was actually reconstructed then perhaps they will recall details which did not occur
Sample used in experiment 2
150 seattle students divided into 3 groups of 50
Dependent variable in procedure 2
The number of participants who will report seeing broken glass 1 week after seeing a staged car crash clip being asked critical question
Independent variable in procedure 2
3 conditions participants in dependent on critical question asked
Critical questions in procedure 2
‘How fast were cars going when they smashed?
‘How fast were cars going when they hit?
No question = critical question
Apparatus of procedure 2
A clip of a staged car crash
Survey with critical questions + smokescreen questions
Stage 1 of procedure 2
Participants will all watch the same clip of a staged car crash then immediately after complete the survey
This had critical question with a verb changed which could distort memory
Stage 2 of procedure 2
Wait a week
Then complete a different survey with 10 questions about the accident
The critical question would be ‘did you see any broken glass?’
How would memory be shown to be distorted in procedure 2?
By participants saying they saw broken glass when there wasn’t showing they had reconstructed memory to believe the accident to be more severe due to critical question saying ‘smashed’
What type of data was collected in procedure 2?
Nominal quantitative data
Headcount of how many said yes to broken glas
How many participants in smashed group report seeing broken glass?
16/50
How many participants in hit group report seeing broken glass?
7/50
How many participants in control group report seeing broken glass?
6/50
Conclusion of experiment 2
LEADING QUESTIONS asked after the event contribute to the information gained after the event (changes reconstruction of someone’s memory)
Explanation + discussion
Memory consists of: info gained during original event and after
Meaning participants were lead to believe the crash was more severe in ‘smashed’ condition and severe crashes usually mean broken Glass (schema) so participants memory reconstructed to believe glass was present
Strengths of ethics
Participants kept confidential
No harm caused because film had no gore
Participants allowed to withdraw
Gave informed consent to watch videos
Weaknesses of ethics
Use of smokescreen questions to conceal critical question meant slight deception
Strengths of data in this study
All quantitative data which can be easily compared and more objective
Weaknesses of data
No qualitative data collected to find why participants self reported those numbers
Strengths of construct validity
Lab experiment had meant there were many controls so memory was being measured and not an extraneous variable
Included smokescreen questions to conceal aim of study which could lead to demand characteristics
Reduced order effects by playing films in different order in experiment 1
Weaknesses of construct validity
Participants may guess answers rather than remembering so not an accurate measure of their memory especially knowing they’re in study
How this study is not ethnocentric?
Memory and cognitive processes are not specific to a culture so no assumption it is the same for all cultures
Weaknesses of ethnocentrism
Other cultures not in this university sample not reflected in their memory ability
Strengths of sampling method
Using opportunity university sample is convenient
Weaknesses of sampling method
University students not representative of whole population: may have different cognitive abilities and compliance to authority: more demand characteristics?
Strengths of reliability
Internal: highly standardised for all participants as they all watched the same clips and had same survey
Results reliable due to repeated to show same findings
External: 50 ps per condition in procedure 2 was enough
Proves consistent effect
Weakness of reliability
9 participants per condition in procedure 1 was not enough
Weakness of Ecological validity
Lab experiment is not similar to real life:
Given a pre warning to watch a car crash
Wasn’t unexpected
Own safety not put at risk
Perhaps if it were real, distress could have a different effect on memory not measured here
Strengths of ecological validity
They were interviewed right after the staged crashes were shown
