Capacity of memory - Volume of information/data that can be stored in any memory
store at any one time
Coding of memory - Process by which sensory information is modified and stored in
the brain
Types of memory stores - Sensory memory (SM), Short-term memory (STM), Long-
term memory (LTM)
Capacity of sensory memory - Very large capacity, not typically aware of it
Capacity of STM - Limited capacity (between 7+/-2 items)
Capacity of LTM - Potentially unlimited capacity
Assessment of STM - Measured using a digit span task, remembering numbers
Jacob's 1887 research on capacity - Found average span for numbers to be 9.3
items, for letters the average decreased to 7.3 items
Miller's research on capacity - Concluded that 'the magic number is 7 plus or minus
2', people can recall around 7 dots, 7 letters, 7 musical notes
Chunking - Process of grouping items together to increase capacity of STM
Cowan's research on STM capacity - Capacity of STM is closer to 4 chunks of
information
Simon's research on STM capacity - Found that people have smaller STM capacity
with larger chunks, supporting the limited capacity of STM
Jacob's research on age and digit span recall - Digit span recall increased steadily
with age, showing possible increase in brain capacity or development of better
strategies
Ecological validity of capacity research - Findings lack ecological validity as research
often carried out in artificial settings
Duration of sensory memory - Less than one second
Duration of STM - Approximately 18-30 seconds unless information is rehearsed
Duration of LTM - Potentially lasts infinitely
Procedure of Peterson & Peterson - Participants given consonant trigrams and
three-digit numbers, asked to recall after intervals while counting backwards