Coding, Capacity, and Duration of Memory
AO1
1. Coding is how information is stored in memory
2. Baddeley’s research found that it is coded acoustically in STM and
semantically in LTM
3. Capacity is how much information can be stored in memory
4. Jacobs’ digit span research found the capacity was 9.3 digits and
7.3 letters, Miller found the span to be 7+/-2 items and that
putting items together extends STM capacity (chunking)
5. Duration is how long information can be stored in memory
6. Peterson and Peterson found duration of STM to be up to 18
seconds without rehearsal, Bahrick et al. (yearbooks) found that
90% recognised faces after 15 years, but recognition dropped to
70% after 48 years
AO3
Artificial stimuli in coding research: Lacking validity in capacity
the word lists had no personal research: could be extraneous
significance variables such as distractions
High external validity in duration of Other explanation in STM duration
LTM: meaningful real-life research: Peterson and Peterson
memories, showed greater recall may have measured displacement
than LTM studies with meaningless rather than decay
material
, The Multi-Store Model of Memory
AO1
1. Sensory register: iconic, echoic, and haptic stores with very short
(milliseconds) duration and high capacity
2. Sensory register is transferred to STM through attention
3. Short-term memory: coded acoustically with a capacity of 7+/-2
items and a duration of 18-30 seconds
4. STM is kept there by maintenance rehearsal and transferred to
LTM by elaborative rehearsal
5. Long-term memory: unlimited capacity and duration (up to a
lifetime), coded semantically
6. LTM is created through elaborative rehearsal
AO3
Supports different memory stores: More than one type of STM: studies
the case of HM – had surgery to of amnesia (KF case study) show
remove his hippocampus to treat different STMs for auditory and
epilepsy and he was unable to visual information
form new LTMs but could form
STMs
More than one type of LTM: the Supporting research: studies into
Clive Wearing case study suggests coding and duration demonstrate
there’s more than one LTM store, differences between STM and LTM
he couldn’t recall events but still
knew how to play the piano and tie
shoelaces