Coding, Capacity and Duration

Coding

The process of converting information from one format to another and the format it is stored in

Baddeley found that immediately people did worse with recalling acoustically similar words

After 20 mins they did worse with semantically similar words

Suggests that the STM codes accoustiaclly

Suggests that the LTM codes semantically

Used artificial stimuli and so lacks external validity because the results cannot be generalised to meaningful memories


Capacity

How much information the STM can hold

Jacobs found that the mean number of numbers participants could remember was 9.3 and the mean number of letters was 7.3

Done in old, uncontrolled labs, lacks internal validity

Recent, more scientific studies have confirmed findings

Miller found that things seem to come in 7's in everyday life eg days of the week

Duration

The amount of time information can be stored for

Peterson asked people to remember information for different durations, they counted down to prevent rehearsal

Found that the duration of the STM is very low because after 18 seconds recall was poor

Artificial stimuli

Bahrick’s yearbook study found that after 15 yrs photographic recognition was 90% and recognition of names was 60% and after 48yrs it was 70% and 30%

High external validity

Individual differences, some people would look at their year book more than others