MEMORY Flashcards
(13 cards)
Peterson and Peterson findings
-After 3 secs-80% recalled correctly.
-After 18 secs- fewer than 10% recalled correctly.
-STM has a duration of between 18-30 seconds
Bahrick et al duration of LTM
-duration of LTM was studied by Bahrick et al (1975) using 392 17-74 year olds
Recall was tested using year books
(1) Photo recognition task
90% accuracy if graduated within 15yrs.
70% accuracy if graduated within 48yrs.
(2) Free recall task.
60% accuracy if graduated within 15yrs.
30% accuracy if graduated within 48yrs.
MSM
Environmental stimuli
Sensory memory
-iconic-visual elements
-echoic-auditory elements
-other sensory stores
-capacity for sensory memory is very large-always taking in information via senses-lot of space to hold a lot of things
-duration very short
attention-bits of information we pay attention to-arrow to short term memory
short term memory-duration 18-30s-capacity of 7+/-2 items-coded acoustically
spinning arrow looping around STM- maintenance rehearsal-repeating information to ourselves to keep in minds-kept in STM-do this for long enough it becomes prolonged rehearsal-moves information to LTM
arrow to LTM labelled rehearsal-arrow back to STM labelled retrieval-brings LTM information back to STM
forgetting
sensory memory-decay-information not payed attention to fades to nothing
STM- decay and displacement-new memories push old memories out STM
LTM-interference and retrieval failure
MSM-limitation-different types of STM
The MSM states that STM is a unitary store i.e. there is only one type. However evidence from patients suffering from amnesia suggests that this is not true.
Shallice and Warrington (1970) studies a patient known as KF.
KFs STM for digits was very poor when they read them aloud to him, but his recall was much better when he was able to read digits to himself. This suggests that there is more than one ST store - one for sounds and one for images.
Such research challenges the MSM as it shows that there must be at least 2 types of short-term store, rather than just 1 unitary store as the model suggests.
strength- types of ltm
Supporting from clinical studies of patients with amnesia.
HM and Clive Wearing, both sufferers of amnesia. HM displayed normal functioning in his semantic memory (e.g. He understood the concept of a dog), but impaired functioning in their episodic memory (could not remember having owned a dog).
Clive Wearing was a professional musician and could play the piano without difficulty, however could not remember having learnt to play, suggesting an impaired episodic memory but functioning procedural memory.
Both of these cases support the idea of a clear separation of different types of LTM.
strength types of ltm
There is also evidence from brain scan studies that different types of memory are stored in different parts of the brain.
Tulving et al. (1994) asked their participants to perform various tasks whilst scanning their brain with a PET scanner.
They found that semantic memories involved the left prefrontal cortext whilst episodic memories involved the right prefrontal cortex.
Supports Tulving’s theory as it shows there is a physical reality to the different LTM stores. These findings have been confirmed many times in later research, further supporting the validity of the finding.
GO OVER WORKING MEMORY MODEL
GO OVER WORKING MEMORY MODEL
interference
Studied retroactive interference by changing the amount of similarity between two sets of material.
Participants had to learn a list of 10 words until they could remember them with 100% accuracy.
They then had to learn 1 of 6 new sets of words.
Interference appears to be strongest when the material is most similar-synonyms
list either synonyms, antonyms, unrelated adjective, consonant syllables
Loftus and Palmer
Aim-investigate effect of leading questions on accuracy of eyewitness testimony
Method: The sample was 45 American students, who were divided into five groups of nine. In an independent measures design, all of the participants watched a video of a car crash and were then asked a specific question about the speed of the cars. Loftus & Palmer manipulated the verb used in the question, for example: “How fast were they cards going when they smashed/ collided/ bumped/ hit/ contacted with each other?”
Result: They found that the estimated speed was affected by the verb used. For example, participants who were given the verb ‘smashed’ reported an average speed of 40.5 mph, whereas participants who were given the word ‘contacted’ reported an average speed of 31.8 mph, an overall difference of 8.7 mph.
Conclusions: The results show clearly that the accuracy of eyewitness testimony is affected by leading questions and that a single word in a question can significantly affect the accuracy of our judgements.
Gabbert
Aim:To investigate the effect of post event discussion on the accuracy of eyewitness testimony
Method: Each participant watched a video of the same crime, but filmed from different points of view. This meant that each participan could see elements of the event that the other could not. E.g. only one of the participant pairs was able to see the title of a book being carried by a woman in the video.
Results:It was found that 71% of participants mistakenly recalled aspects of the events that they didn’t see in the video but had picked up in the discussion. In the control group, where there was no discussion, this figure was 0%.
Conclusion: PED reduces the accuracy of EWT due to memory contamination and memory conformity.
Memory contamination is when cold witnesses to a crime discuss it with each other, and then their eyewitness testimonies become altered or distorted because they combine information from other witnesses with their own memories. Whereas memory conformity is the fact that witnesses often go along with each other, either to win social approval or because the other witnesses are right and they are wrong. Unlike memory contamination, the actual memory is changed in this case
the negative impact of anxiety-Johnson and Scott
Johnson & Scott (1976)
PTs heard and arguments in the next room, whilst seated in the waiting area.
All PPTs were in either a low or a high anxiety condition.-low-participants saw person walk out office with a pen dripping ink-high-participants saw person walk out office with knife dripping blood
Recall was worse in the high anxiety condition when asked to describe the person walking out.
49% vs. 33% Recall.
weapon focus effect
the positive impact of anxiety-Yuille and Cutshall
Yuille & Cutshall (1986)
PPTs were all witness to a shooting in a shop.
There were 2l witnesses.
13 agreed to take part - 4-5 months after the incident - compared to the original police report.
Participants were also asked to judge their stress
(7-point scale)
Recall accuracy and stress levels at the time of the event were recorded.
Recall was better when stress levels were high:
88% vs. 75%
