The multistore model

• THERE ARE THREE STAGES TO THE MULTISTORE MODEL

1) The sensory register- Data from the environment via the senses is taken to the sensory register in a raw uncoded form e.g echoic or iconic

2) The STM- if we pay attention to a sense in the sensory register then the information is taken to the short term memory where there is a duration of about 30 seconds, the encoding is mainly acoustic which means it uses auditory stimuli to implant memories

3) The LTM- if we think about this information in our STM repeatedly (elaborative rehersal) then it is stored in the long term memory where encoding is usually sematic which means the meaning of words are used to remember. Our LTM is never ending but it is hard to access the memories in order to move them back to the STM

• In the multistore model there is a maintenance loop (phonological loop) which deals with written and spoken information

• memory- the cognitive function of retaining and retriving information about events, images or ideas
• memory is central to all cognitive processes (thinking, knowing, remembering, judging ect)
• coding- the form in which information is stored- echoic, iconic,haptic ect
• capacity- the amount of information that can be stored in the memory
• duration- the amount of time information can be stored for in the memory
• encoding- means the original form in which inforation is stored and transmitted

Jacobs (1887)

• discovered that we have a digit span between 5 and 9 (millers magic number 7+/2-)
• we can increase capacity of STM by method of chunking which is  converting individual numbers/letters or words into small groups to remember

Baddley (1999)

• discovered that reading numbers aloud increases the digit span showing that echoic memory backs up the STM
• word length effect test shows that pronouciation is important e.g its harder for kids to pronounce long words so adults would remember more
• capacity- number of items that can be remembered in 1.5-2 seconds

Conan

• used nonsence words and sounds to reduce familiarity to the LTM which resulted in capacity reducing to 4 items

Peterson & Peterson (1959)

• showed nonsense trigrams ( e.g MDX, FTH)
• prevented rehersal of the trigrams by using the Brown peterson technique which is counting back from large numbers in threes
• conclusion- duration of stm Is 20 seconds
• criticisms- with nonsense trigrams people can find ways to remember them by relating them to words or people ect / also interferance activities like numbers replacing letters can occur

Rietman

• used tones instead of numbers for the same test as the peterson and peterson one and the duration of the STM was 96 seconds showing that the STM is again acoustic not sematic because people made less mistakes when asked to remember sounds instead of letters

Bahrick et al (1975)

• aim- people dont remember things form ages ago because they are asked about things that aren't special to them. Bahrick wanted to observe the duration of the LTM in a natural setting that has significance to the participant. He also wanted to compare verbal adn visual LTM.

procedure

• 400 participants of ages between 17-74
• recall test asked participants to recall individual names from graduating class
• photo test using photos from their year book
• name recognition test using ex-school friends
• photo and name matching test

findings

• participants within 15 years of graduating were 90% accurate at recognising faces and names (visual and verbal) but after 48 years 90% declined to 80% for names and 70% for photos
• free recall was bad- after 15 years= 60% and after 48 years=30% accurate

conclusions

• evidence of long term memories up to 57 years but memory loss did occur but faces and names recall went just as well
• recognition was better than recall (visual)
• this means the brain had lots of information but we cannot always recall it as it isnt easily accessed from LTM

criticisms

• they can rehearse the knowlege
• little motivation to remember
• participants who were younger more recently looked over the year booK

The LTM is most sematic- Baddley read a list out and got people to record it

Alan Baddley (1966)

• aim- to figure out whether coding in the STM and LTM is mainly acoustic or sematic

proceudre

• 75 participants shown 1 of 4 word lists, repeated 4 times
• 1- acoustically similar words
• 2-acoustically disimilar words
• 3-sematically similar words
• 4-sematically disimilar words
• for testing the STM the participants were given a list containing original words they saw by ordered differently, they were asked to put them in order
• for testing the LTM the partipants were asked to do the same test by 20 minutes after the test

findings

• for the STM recall of acoustically similar words was worst at 10% because they confused words, other tests were good at 60-80% accuracy
• for the LTM the recall of semantically similar words performed worst at 55% because they again confused words, other tests were good at 70-85% accuracy

conclusions

• STM- lots of confusion of similar sounding words so suggesting it is coded on a acoustic basis
• LTM- lots of confusion on semantically similar words suggesting it is coded on that basis

evaluations

• findings make cognitive sense- you are more likely to recall something out loud
• small difference between acoustic and semantic results shows that semantic could be possible in the stm
• this was a lab study so shows causility but lacks validity as its not real life events- could be replicated to check results

strengths+weaknesses

• there is evidence of seperate memory stores, studies show different capacities and durations of the three stores
• Glanzer and Cunitz created the serial position curve- words called out and asked to be recalled in whatever order, people remember lots of the first words(primary effect) and last few(recency effect)
• evidence from brain damage patients like Clive wearing who suffered extreme brain damage, remembered no short term memory and hardly any LTM but can remember long term things like how to play piano and his wifes name which suggests the LTM is not one single store
• HM had a labotomy to cure epilepsy lost memories except ones before operation and cannot make new ones suggesting the LTM and STM are seperate. But his recall of events suggests again there are multiple LTM stores
• Kf had a motorcycle accident which resulted in brain damage, he can only remember 1/20 digits and has no STM, visually presented words remembered better than spoken showing maybe STM is more complex than msm says

Ruchkin- found that you can remember around 7 words in the STM but only 4 sudo words in the STM which shows words that people understand and recognise are easy to remember