psychology - memory

Multi-Store Model

Represents how memory works using sensory register, short term memory and long term memory

Developed by Atkinson and Schiffrin

Sensory Register

• Encoding - modal specific

• Capacity - high

• Duration - ½ or ¼ of a second

Short Term Memory

• Encoding - acoustic

• Capacity - 7 ± 2

• Duration - 18-30 seconds

Long Term Memory

• Encoding - semantic

• Capacity - unlimited

• Duration - permanent

Encoding Definition

The way in which information is stored in the memory stores

How is information passed from sensory register to STM

Information is passed if you pay attention to it

How is information held in STM

Maintenance rehearsal ; if it is rehearsed long enough, info is passed to LTM

Study of Capacity of STM

Miller (Immediate Digit Span Test)
Jacobs Support

Strength of capacity of STM research

• Jacob tested STM by reading aloud 4 digits and increasing the amount each time. This was stopped when ppt recalled number sequence incorrectly - average was 9.3 digits

• There was RESEARCH SUPPORT as other researchers found support for his findings

Limitation of research into capacity of STM

• Capacity was overestimated

• Miller found that ppt could recall 5-9 chunks of information whereas there was conflicting research as Cowan(2001) found ppt could only recall 4

Study of Duration of STM

Peterson and Peterson tested 24 students memory by having them recall trigrams after doing a distraction test so they couldn’t use maintenance rehearsal to recall information

Limitation of research into duration of STM

• Peterson and Peterson used artificial stimuli as they asked ppt to recall meaningless trigrams with is not representative of everyday life

Study of encoding into STM

• Baddeley asked ppt to recall words in order they were told.

• He found that we encode acoustically for STM

Strength of research of encoding into STM

• Baddeley’s research identifies two clear and distinct memory stores which led to the development of the multi store model of memory

Limitation of encoding into STM

• Baddeley’s research uses artificial stimuli as ppt recalled random words which were not representative of everyday life

Study of duration into LTM

Bahrick et al conducted a natural experiment where he asked 394 ppt aged 17-74 to identify photos of their high school peers 15 and 48 years after graduation

15 years - there was 90% accuracy

48 years - there was 60% accuracy

Strength of research into duration of LTM

• high external validity

• Bahrick used information that was applicable to real life e.g recognising faces

Limitations of research into duration of LTM

• Confounding variable - ppt may have stayed in contact with their classmates which affects their memory which affects study

Strength of Multi-Store Model of Memory

• Research support for STM and LTM being different stores

• Baddeley found STM encodes acoustically and LTM encodes semantically

Limitations of MSM

• No evidence to support there is more than one STM store

• Evidence to support prolonged rehersal is not needed for info to be passed from STM to LTM

• MSM is outdated - simplifies STM & LTM