Memory Flashcards
Memory
It is the process by which we retain information about events that have happened in the past
Coding
The format that information is stored in the memory stores
Capacity
This is a measure of how much can be held in the memory
Duration
The length of time information can be held in memory
Coding:
Baddeley (1966)
Procedure
Group 1 - acoustically similar (cat,cab,can)
Group 2 - acoustically dissimilar (pit,few,cow)
Group 3 - semantically similar (great,large,big)
Group 4 - semantically dissimilar (good,small,hot)
Pts shown original words and asked to recall them in correct order
Coding:
Baddeley (1966)
Findings
- when recalled immediately after (STM), did worse in acoustically similar
-when recalled 20 minute after (LTM), did worse with semantically similar
these support that information is coded acoustically in STM and semantically in LTM
Coding:
Baddeley (1966)
Evaluation
- artificial stimuli rather than meaningful, difficult to generalise, limited application
+identified clear difference between two memory stores.
Capacity of STM
Between 5-9 items
Capacity for LTM
Unlimited
Research on capacity:
1. Digit span technique (Jacob’s, 1887)
- pts given 4 digits and have to recall them aloud in right order
- if correct given 5 digits, had to recall them aloud
- continued until pt can’t recall in correct order
-determines individuals digit span
Found: mean digit span was 9.3 and mean span for letters was 7.3
Research on capacity:
2. Span for memory and chunking (Miller, 1956)
Miller suggested capacity of stm is 7 plus or minus 2.
People can recall words as well as letters
Chunking:
Grouping sets of digits or letters into units or chunks
Evaluation of capacity
-lacking validity, Jacob’s study: conducted long time ago, lack of control, pts distracted. - result not as valid as there were confounding variables
- not so many chunks, Millers study: overestimated capacity of stm, Cowan found capacity of stm was 4 chunks
Duration of STM
Limited duration of 30 seconds
Duration of LTM
Unlimited, last whole life