Encoding: Made sense of.
Capacity: How much information is stored.
Duration: How long information is stored.
The sensory store
- Participants saw a grid of digits and letters for 50 milliseconds.
- They were either asked to recall and write down all 12 items or told they would hear a tone immediately afterwards and they should write the row that the tone corresponded with.
- Recall was poorer when asked to recall the whole thing (42%)
- Recall was higher when asked to recall one row (75%)
Short term memory
Joseph Jacobs (1887)
- Used digit span and found that the average span for digits was 9.3 where as for letters it was 7.3
- He suggested that it may be easier to recall numbers because there are only 9 digits where as there are 26 letters.
George Miller (1956)
- The span of immediate memory is 7. People Can cope with remembering 7 dots flashing on the screen but tend to have difficulty remembering more than 7.
- The magic number +7 and -2
A way of increasing memory is through a method of called chunking, this means chunking things into things that you remember more easily.
=> Duration refers to how long the information can be held.
=> The duration of STM isn't very long.
Llyod and Margret Peterson (1959)
- 24 students.
- experimenter said a consonant syllable followed by a 3 digits number.
- They had to count backwards from the number in 3's or 4's until told to stop.
- They were then asked to recall the constant syllable.
- counting backwards was to stop the participant rehearsing.
- Participants remembered about 90% when there was only a 3 second interval.
- only recalled 2% when there was an 18 second interval.
Conrad (1964) suggested that STM codes all information acoustically (according to sound)
- Participants were given a list of consonants. for example: PJNRZD for about 3/4 of a second.
- Asked to recall what they had seen.
- They found that errors were linking to letters which has a similar sound.
- This is referred to as acoustic confusion.
Long Term Memory
=> LTM refers to memories that last any where between 2 hours and 100 years
Bahrick et el (1975)
- Asked people of various ages to put names to the faces in their high school year book.
- People had 70% accurate recall.
- This may be because the information needed to be recalled was of more importance.
- He tested the effects of acoustic and sematic similarity on STM and LTM recall.
- Gave participants a list of words which were acoustically similar…