- Created by: mayaclift
- Created on: 18-11-18 16:21
Multi-store model of memory
Atkinson and Schriffrins
- Duration = 0.5-2 secs (iconic visual, echoic sounds)
- Capacity = 15-20 icons
- Coding = it doesnt have to do anything with it.
Short term memory
- Duration = limited no longer then 30 seconds
- Capacity = limited 5-9 items (magic number 7)
- Coding = acoustic coding which focuses on how the information sounds.
Long term memory
- Duration = Infinate
- Capacity = Limitless
- Coding = put in the long term memory with an attached meaning to it.
Studies for the multi-store model
Short term memory capacity = Jacobs = used a serial digit span, he gave the participants one number/ letter to recall. If they got it right they were given 2 to recall and so on. He found the average span was 9.3 for number and 7.3 for letters because there are more letters.
Short term memory duration = Peterson and Peterson = gave participants trigrams. They were given one trigram at a time and were asked to count backwards in 3 from a given number. They found that recall became poorer the longer the retention interval. After 3 seconds 80%, 6 was 50%, 8 was 10%.
Long term memory capacity = Standing et al = gave 2560 photos to participants for 5 or 10 seconds. Recall was tested 1-2 days later, Participants had to recall which people they had seen out of pairs where one was seen and the other was unseen. This produced 90% success rate.
Long term memory duration = Bahrick et al = asked 392 americans to complete tasks that involved people from when they went to highschool. It was found that their recall was very good, 80% name recognition.
Long term memory coding = Baddley = gave similar or disimilar words, similar words were worse.
Multi-store model evaluation
Evidence for amnesiacs
- Clive wearing = had a virus that attacked his brain. He lost most of his LTM but his STM was still intact. He can no longer form any new LTMs, and his life operates on 30 second intervals. This supports the idea that the STM and LTM are different stores.
- KF = had a motorcycle accident and damaged his STM but LTM was still intact. Which supports that they are seperate stores, but looking closer, the model suggests that it goes from STM to LTM, so how is he still forming LTM, which suggests its a lot more complex.
Research support - the serial position effect
- Murdock = participants were to remeber lists of words, immediately after they were to recal as many as possible in 1.5 minutes. He found that words at the start and the end of the list were being recalled, words at the start have been rehearsed, words at the end were in STM
Evidence against - the role of rehearsal
- Glenberg et al = were to rehearse words 1, 3, 9 times and found only 1.5% increase.
Types of LTM
Episodic = Tulving = this is where we remebers specific 'events', such as getting married, graduating from university. They can also be less significant such as what you had for breakfast or what you did on the weekend. These are more likely to be forgotten and are described verbally.
Semantic = Tulving = our general knowledge about the world, concepts, facts. This is highley organised and won't be forgotten.
Procedural = our ability to recall how to do something, such as riding a bike, drive or play an instrument. They are difficult to explain and are fact based.
Evaluation for types of LTM
Evidence for amnesiacs = HM was a patient who suffered memory loss due to experimental surgery, he only lost parts of his memory. It was found that he was able to learn new procedures, however he had no recollection of doing the task showing a damaged episodic memory.
Evidence for amnesiacs = Ewert et al = looked at 16 patients with post traumatic amnesia. They were given tasks to test their procedural and episodic memory. It was found that their performance on episodic tasks was poor, but procedural tasjs was good.
Research into alzheimers patients = Kawai et al = Using the mirror tracing task they found that is was possible for those was ATD to learn and improve new procedural memorys.
Research from brain scans = Klimesch = patients completed a task that used their semantic memory and then another task using their episodic memory whilst been given an EEG. It found that each task was processed differently suggesting that they are two different stores.
Working memory model
Baddeley and Hitch (short term memory)
- where all the information comes and it decides what to do with it, and has the ability to deal with general tasks such as decision making.
- Visual cache = deal with colour and descriptions
- Inner scribe = deals with movement and spacial awareness
- Phonological store = 'inner ear' hold sounds and words.
- Articulary control system = 'inner voice' it repeats information we have heard.
Episodic buffer = processes information from all of the senses.
Evaluation of the working memory model
Evidence for amnesiacs = KF = his STM for verbal material was damaged whereas his STM for visual material was much better, so supports the concept that the phonological loop has been damaged but his visuo-spatial sketchpad is in tact.
Evidence for dual task studies = It states that all four components have a limited capacity. How ever because all components are seperate it shouldn't be a problem to carry out tasks at the same time.
- Robbins et al = had participants choose chess moves. These moves were judged on how good they were. This is a task that uses both the visuo-spatial sketchpad and central executive. When doing the task it was better when saying the word 'see-saw' on repeat rather then pressing keys in a clockwise fasion. This is because the visuo-spatial sketchpad wasn't overloaded.
- Klauer and zhao = Participants were given two tasks to do at the same time. They found that performance was worse when they were given two of the same task such as visual cache and inner scribe. This supports that there are two different components.
Criticism = Central executive unfalsifiable and doesn't exists and its to vague. (Parkin).
Explanations of forgetting = retro and pro interfe
NEW MEMORY INTERFERES WITH RECALL OF AN OLD MEMORY
AN OLD MEMORY INTERFERES WITH THE RECALL OF A NEWER MEMORY
Waugh and norman = they gave participants 16 digits to remeber. They were given one digit to remember and asked to recall the number before. Found that recall was better towards the end of the list. Retroactive interference.
Underwood and postman = Were given word pairs. They were asked to recall the first list of paired words. Found recall was worse for the second group. Newer learning interfered old learning.
Underwood = found that when participants had been given 15 or more lists to learn they would be able to recall 15% of the last list, but 80% when they had one list. Proactive.
Kane and engle = individual differences. Stated that those who could remember more had better working memory spans. Those with poorer working memory showed proactive interference.
Explanation for forgetting:absence of cues
Context dependent = being in a different place at recall then at learning.
State dependent = being in a different mood/state then at learning.
Category dependent = lack of organisation, so cant access original memory.
Godden and baddeley = had divers learn on land or under water. They had to recall the words and found that recall was best at the place of learning.
Goodwin et al = divided 48 male students into either the drunk or sober category. They were given information to learn and then were put in the state and found that recall was best in the state that they learned in.
Abernathy = tested students at the start of a course and then they were tested in either a strange or the same room. It was found that recall was best for those tested in the original classroom.
Limitation = It is often impractical and can be only used to test episodic memory.
Factors affecting EWT: Misleading information
EWT = evidence given by an onlooker at the scene of a crime.
Two types of misleading information:
LEADING QUESTIONS = suggest the answer that should be given.
POST EVENT DISCUSSION = information about the event is talked about and the original memory may become innacurate.
- Loftus and palmer = showed 45 students several film clips of traffic accidents. They were then asked questions, one being how fast they thought the car was going when it smashed, collided, bumped, hit and contacted. When smashed was the word the speed went up to 40.8, where as contacted was 31.8. Showing that leading questions affect EWT accuracry.
- Ecological validity = as it was artificial, and were only watching films, rather then a real crash.
- Loftus and pickrell = looked at the recall of childhood memories, They asked the participants if they had been lost at the mall at the age of 5, and they all said yes, even though relatives said that they hadn't, and also gave information about the even that didnt happen.
- Loftus = watched a road traffic accident where a pedestrian had been knocked over, they were offered money if they answered questions correctly, 70% made a mistake on a question.
Factors affecting EWT: anxiety
Loftus = had particiapants arrive at a laboratory. They were told to wait outside for the study to begin. In the 'anxiety' condition the participants overheard a heated conversation, glass breaking and then saw a man leave the room with a blood stained knife. In the 'non-anxiety' condition participants overheard a low key conversation, equipment failure and saw a man leave the room with a knife. Participants were then asked to show what the man looked like. 33% recognised the man from an anxiety room, and 49% of the non anxity.
Mueller et al = gave 96 participants a test of anxiety. They gave them 50 black and white photos of faces one at a time. They were then mixed randomly and then were shown with another picture they hadnt seen and had to say which one they had seen. It was found that participants with higher anxiety scores performed less.
Christianson and hubinette = questioned 110 witnesses who between them had witnessed 22 bank robberies. Each feeling some anxiety. But every person had exceptional recall, which goes against loftus research.
Yuille and cutshall = examined real life events of robbery. They interviewed the witnesses and found that those who were the most anxious at the event had the best recall.
Improving the accuracy of EWT
Standard police interview = there is no real structure. They guide the interview in a certain way. The questions are predetermined, and are often leading and are a forced choice. This makes them feel like they have no choice but to answer, which inimidates the interviewee, and will most likely give incorrect recall.
The cognitive interview =
- Context reinstatement = they are asked to recreate both the internal and external context, this helps recall as it uses cues.
- recall everything = they are told to recall everything and can be in any order.
- recall in different orders = put the information in some sort of order.
- recall from different perspectives = recall the information from somebody elses point of view e.g. the witness or offender.
Enhanced cognitive interview = they should be encouraged to relax and speak slowly, the interviewer should minimise distractions, interviewer should activley listen, interviewer should pause after each response, interviewer should adapt their language to suit the witness.
Evaluation of the cognitive interview
Geiselman et al = showed 89 participants police training films. They were then asked using the standard police interview, cognitive interview or hypnosis. They found that the cognitive interview led to a higher percentage of accurate recall than the standard interview.
Geiselman et al = found further support for the cogntive interview. In this study the entire classroom was wearing a blue rucksack. The intruder then stole a projector. They were then questioned using the cognitive interview. They were then asked what colour the rucksack was, and found that the cognitive interview group gave the best recall overall and were less likely to be influenced by leading questions.
Kebell et al = surveyed police officers in the UK. They found that whilst the cognitive interview can lead to an increase in recall it does not decrease incorrect statements. This is a problem as it still means that there is some unreliability to what the eyewitness are saying. Also that the time that it takes for the cognitive interview to be carried out takes a long time.
Geiselman = found that the age of the witness is a factor. He found that the cognitive interview worked less well for children under the age of 6. This is because they might find the instructions difficult to understand, so the information is unreliabe.