WEEK 3 - memory decay and distortion

eyewitness memory is what>

reconstructive

the status of memory may be altered between encoding and retrieval because of what?

• passage of time

• intervening knowledge/experience

• misinfromation

who came up with the passage of time and the forgetting curve? what does he suggest?

herman ebbinghaus

interview as quickly as possible

curves and slows down

memory decays quickly and plateaus over time

tested it himself

what is the function of memory?

to guide your future

synder and uranowitz conducted a study on intervening knowledge/ experience - they made participants read history story about betty k, immediately or one week later they were told betty k was either homosexual and heterosexual. what was then found?

they assessed their memory for the history story and found that:

• delay did not exert an effect on participants responses

• participants made more label-consistent errors than label-inconsistent errors

• (consistent with the label you got = label consistent)

what is hindsight bias?

when knowledge of current events, emotions , or outcomes biases judgements and memory of processes leading up to them

can influence both judgements about what happened and memory of what happened

david, lopez and koyama conducted a study on intervening knowledge and experience and conducted a study where participants listened to an argument between a couple, what did the study consist of and what did they find?

• half participants were told that the couple had broken up

• half had been told that the woman had been found dead and that her boyfriend was charged with murder

• memory for conversation was assessed

found:

participants in murder condition

• more likely to accurately remember that the man had made threatning statements towards the girl

• more likely to inaccurately recall that he had hit her and threatened her classmate

this contaminated their own memory

who came up with the term misinformation? describe the standard process of it

elizabeth loftus

event - misled - interviewed

if you feed people incorrect information they will incorporate it into their own memory

loftus conducted a study on the media where they showed participants 4 minute video clip of a robbery and shooting - then exposed them to a tv report which either contained misinformation or no misinformation. What was measured and found?

measured:

• evaluation of news presenter

• memory for videotape

found:

• control group were highly accurate compared to misinformation group

• almost 1/3 of misinformed participants incorporated the misinformation into their memory

what percentage of witnesses engage in co-witness discussion? what do they report as the primary prupose of these discussions?

86%

provide information and exchange information

what are the advantages of co witness discussions?

• prompt witnesses to recall forgotten details

• may reinforce memory

• aid recover from trauma

• paint a more accurate overall picture

what are the disadvantages of co witness discussions?

• contaminate independent recollection

• weaken the prosecution case

• witnesses may become unsure of their testimony

• may lead to reports of common things

• collusion

what is a real example of a co witness discussion which had impacts?

oklahoma bombing

what concept did solomon asch develop?

conformity - to conform to other people in social situations

what are the 2 reasons you might conform?

1. normative conformity - follow group norm

2. informational conformity - think you are wrong and they are right

within co witness paradigms explain these

• MORI technique

• confederate paradigm

mori - look at same screen and see two different things

confederate - saw the same thing, but experimenter says they saw soemthing else

gabbert, memon and allan conducted a study on co-witness discussions and looked at pairs of participants watching a stimulated crime, each watching a different crime. half of the participants were allowed to discuss the crime after before being interviewed individually. What was found?

• 71% of participants in the discussion condition reported items that they had not seen

• none of the participants in the control condition reported unseen items

• 60% of participants who had not seen the theft declared the girl guilty of stealing after discussing with a co witness who did

what is the illusory truth effect?

even the simple act of repeating a statement can increase the strength of ones belief in its truth

even in the absence of any input from a conversational partner, people asked to recall a witnessed event what?

• bias their descriptions to reflect their own goals

• report believing these biased descriptions

• falsely recall the original stimli as consistent with their biased descriptions

allport conducted a study where they showed participants photos of a shabby dressed white manholding a razor arguing with an unarmed, well dressed black man, what did they find?

in retellings, over half the participants transposed the characters

what are the 4 possible mechanisms of misinformation?

1. person reports the misinformation, but knows that its wrong

2. the original memory gets overwritten or changed

3. there are now two memories but the original one becomes inaccessible or the person cant distinguish between the two

4. there was no original memory (no encoding)

toland conducted a stuyd on the possible mechanisms, the followed the standard misinformation procedure and were asked to bet money on their answers. Betting behaviour suggested high belief in false suggestions. what did they find?

they were believing the misinformation

rachel zajac et al conducted a study on possibe mechanisms where they were in pairs and one was a confederates. Half the particiapnts were believed that the confederate was consuming alcohol. What did they then do and find?

• watched a video of a theft

• discussion before interview - confederate gave 2 pieces of misinformation

found:

• when pre-misinformation response was discrepant with the misinformation, participants were more likely to accept misinformation from the ‘sober’ co witness than the ‘drunk’ one

• when participants were unable to provide a pre-misinformation response, co-witness condition had no effect on misinfo acceptance

what are the implications for eyewitnesses?

• what happens between the event and the memory interview is the msot important

• eyewitnes evidence should be treated as we treat physcial evidence

• distortion can be minimised, but can’t always be avoided