Multi Store Model of Memory Flashcards
(14 cards)
Features of the MSM
-The multi store model of memory, proposed by Atkinson and Schiffrin suggests that memory is made up of three compononets: sensory register, short term memory and long term memory
-The MSM is a linear model; meaning that information appears to
flow through the model in one direction
-The MSM is also passive; meaning that stores hold on to information before it is passed on or lost
Sensory register
-The sensory register detects and records all information from the senses, meaning that its coding is modality-specific
-Information is passed to the short term memory through attention
-The sensory register’s capacity is very large and the sensory register’s duration is very short (around 250 milliseconds)
Short term memory store
-The short term memory store recieves information from the sensory register by paying attention
-Information in the STM is coded acoustically
-The capacity of the STM is 7+ or - 2 (Miller’s magic number), this can be improved through chunking (grouping sets of items reduces the overall number of items)
-The duration of STM is 18-30 seconds, meaning that any information that is not passed to the LTM during this time is lost via displacement (new information) or decay (lost over time)
-The STM passes information onto the LTM via maintenance rehearsal (repeating information) or elaborative rehearsal (linking new information to information already in the LTM)
-Information can be passed back from the LTM to the STM during retrieval
Long term memory store
-Information is passed to the LTM from the STM via rehearsal
-Information needs to be passed back to the STM via retrieval
-Information in the LTM is coded semantically (in the form of meaning) and has a potentially unlimited capacity and a duration of up to a lifetime
Evidence for the the memory stores being separate (Murdock’s serial position curve study)
- In Murdocks’s serial position curve study, participants were each given a word list of 10-40 words to free recall after they were all read out
-He found that the words at the start and end of the list were more likely to be recalled than those in the middle
-This provides evidence for short term and long term being separate stores as the words at the start entered the LTM and were recalled (Primacy effect), and the words at the end of the list were held in short term memory and recalled (Recency effect)
-Words in the middle of the list were held in short term memory before being displaced by later words
Sperling (1960) capacity and duration of sensory register (grids)
-Sperling (1960) flashed 3 by 4 grids of 12 letters to a group of trained participants for 1/20th of a second; he then asked them to recall a specific row that had been signalled to pay attention to before with a different type of beep for each row
-The participants recalled this one row with a over 75% accuracy, suggesting that the sensory register has a higher capacity than the short term memory
-When Sperling asked participants to recall the whole grid, they were only able to recall the first 4 to 5 words, suggesting that the information faded from the sensory register before it was able to be paid attention to and passed to the short term memory
-This suggests that the duration of the sensory register is less than 1 second
Baddeley (1966) support for the coding of short term memory or long term memory (acoustically similar and dissimilar words)
-Baddeley (1966) gave participants four ten-word lists that were either acoustically similar (group A), acoustically dissimilar (group B), semantically similar (group C), or semantically dissimilar (group D)
-It was found that immediate recall was the worst for group A , while recall after twenty minutes was worst for group C
-This suggests that the short term memory codes acoustically, as the acoustic similarity of the words cause confusion
OR FOR LONG TERM MEMORY:
-This suggests that the coding in long term memory is semantic, as there was confusion when recalling semantically similar words
Jacobs (1887) capacity of short term duration + Miller chunking
-Jacobs (1887): participants were given lists of letters or numbers and asked to recall them.
-It was found that the average capacity for letters is around 7 and the average capacity for numbers is around 9 (usually stated as 7+ or -2)
-This suggests that short term memory has a very limited capacity, however Miller suggested that capacity can be increased using chunking (grouping together words to reduced the overall number of words)
Peterson and Peterson (1959) (Trigrams) duration of short term memory
-Peterson and Peterson (1959): participants were shown a three letter trigram (e.g XBV) and a three digit number
-Participants were given a delay period of either 3 seconds, 6s,9s,12s,15s or 18s before being asked to recall the trigram
-Researchers gave the participant the interference task of counting backwards in 3s or 4s from a random number provided by the researcher to prevent maintenance rehearsal
-It was found that after 3 seconds, participants recalled the trigram about 80% of the time, compared to the significant drop in recall after 18 seconds at 10%
-This study demonstrates that the duration of short term memory is very short and that rehearsal is needed to prevent the loss of information
-It also demonstrates that decay (loss over time) is the primary way that information is lost from the short term memory store
Wagenaar (1968) diary entries : capacity of long term memory
-Wagenaar (1968) wrote a diary recording over 2400 events over the course of six years
-When testing recall, he found that recall of particular events was around 75% after 1 year and around 45% after 5 years
-Additionally, his sense of remembering events (retention judgement) was a high 80% after 5 years, suggesting that the capacity of long term memory is very large, potentially unlimited
Bahrick (1975) Duration of long term memory (school photos)
-Bahrick (1975): participants aged 17-74 were shown old photographs of school friends and asked to match faces to names
-It was found that recall of matching face to names was 90% after 15 years, and still 80% after 48 years
-This suggests that the duration of long term memory is very large, potentially permanent in some cases
Multi-store model additional evaluation (low external validity + ecological validity + mundane realism) (negatiev evaluation)
-Experiments used to test aspects of the multi store model often lack external validity and ecological validity, as the results collected in lab settings may not be generalisable to real world situations
-They also lack mundane realism, as the artificial tasks used are dissimilar to those usually completed in people’s everyday lives
Negative additional evaluation of MSM (researchers have to make inferences)
-Since memory models are not directly observable, researchers need to make inferences based on behavior observed during experimentation
-These inferences are effectively educated guesses and could be incorrect
Negative additional evaluation of MSM (STM and LTM not unitary stores)
-Later research has demonstrated that both LTM and STM are not unitary stors
-There are different types of short term and long term memory that is explained by the working memory model
