The multi-store model of memory Flashcards
What 3 stores does the MSM consist of?
Sensory Register, short term memory and long term memory
How are the stores described?
As unitary, separate stores
How does information pass through each store?
In a linear way
What is coding?
the format in which the information is kept
What is capacity?
the quantity of information that can be stored
What is duration?
how long it can be stored for
Describe what the sensory register does
Takes info from the environment via one of the sense organs and holds it in that same form store. There is a store for each of the senses.
What is the key process of the SR
Attention - if we pay attention the information passes onto STM store.
How is the sensory register coded?
Sense specific
e.g. iconic store codes visual information and the echoic store codes auditory information
What is the capacity of the Sensory Register
Very high/large
What is the duration of the Sensory Register?
Less than half a second
What is the main process of STM?
Maintenance Rehearsal - when we repeat info over and over to ourselves. If we rehearse it for long enough (prolonged rehearsal) the information passes from STM to LTM. Information can decay if there is no maintenance rehearsal.
How is STM coded?
Acoustically (Baddeley’s research)
What is the capacity of STM?
Small capacity of 7+/- 2 items (Jacob’s and Miller’s research)
What is the duration of STM?
lasts less than 18-30 seconds unless it is rehearsed (Peterson and Peterson’s research)
Describe the LTM store
This is where information is stored if it is properly rehearsed in the STM.
What is the main process of LTM?
Retrieval - information can be recalled back from LTM to use in STM.
Forgetting is due to interference, retrieval failure or decay.
Who did research on coding and what store?
Baddeley (1966) STM and LTM
Describe Baddeley’s study
Participants were given 4 sets of words to recall in order
1) Acoustically similar (sound the same) e.g. cat, mat
2) Acoustically different (sound different) e.g. dog, bin, cup, pen
3) Semantically similar (similar meaning) e.g. big, large, huge
4) Semantically dissimilar (different meaning) e.g. huge, good, light, blue
What did Baddeley find about STM coding?
When participants were asked to recall the words in order immediately, they made significantly more mistakes on words that sounded alike.
What did Baddeley conclude about coding in the STM?
STM information is coded acoustically so when we recall information from STM similar sounding words get confused.
What did Baddeley find about LTM coding (participants)
Participants were asked to recall after 20 minutes. They were far more likely to confuse semantically similar words (have a similar meaning) than semantically dissimilar words.
What did Baddeley conclude about coding in the LTM?
LTM is coded semantically (by its meaning). So when we recall information from LTM, similar meaning words get confused.
Who researched capacity and in what store?
Jacobs (1887) and STM
What happened in Jacobs’ study?
Measured digit span. Read out digits/letters to participants. Increased the length of these digits by one each time until the participant could only accurately recall the information in the correct order.
What did Jacobs find?
The mean span for digits was 9.3 and for letters was 7.3
What did Miller find?
STM has a capacity of between 5 and 9 items.
7+-2
Who did research on duration and what store?
Peterson and Peterson (1959) of STM
Describe Peterson and Peterson’s study
Participants were presented with trigrams (three consonants). Vowels were avoided so words couldn’t be constructed. Participants were then asked to count backwards in 3s from a 3 digit number. They were then asked to stop after varying periods of time e.g. 3,6,9,12,15&18 seconds (the retention interval) and recall the trigrams.
What did Peterson and Peterson find?
after 3 seconds, average recall was 80%, and after 18 seconds it was about 3%
What did Peterson and Peterson conclude?
Duration of STM is 18-30 seconds.
Who did research on duration of LTM?
Bahrick et al (1975)
What were the aims of Bahrick’s study?
- To investigate the duration of Very-Long-Term-Memory (VLTM).
- To see if memories can last several decades.
Describe the procedure of Bahrick’s study
• An opportunity sample of 392 American ex-High-School students aged between 17 and 74 was used. The time since leaving High School was up to 48 years. The participants were tested in four ways:
- Free recall of the names of as many of their ex-classmates as possible.
- A photo recognition test. The participants were asked to identify their former classmates from a set of 50 photos.
- A name recognition test.
- A name and photo matching test.
• Very Long Term Memory was assessed by comparing the participants’ responses with yearbooks of all the students in that year.
What did Bahrick find?
photo recognition - 90% accuracy within 15 years of graduation and after 48 years it declined to 70%
free recall - 60% accurate after 15 years and only 30% accurate after 48 years
What did Bahrick conclude?
This demonstrates that people have very-long-term memories
The findings also support the claim that recognition is better than free recall.
