Evidence supports multi-store model (MSM)
Multi-Store Model (MSM)
Human memory are divided into 3 parts: has different duration and capacity
Sensory memory
Requires attention to transfer the info to STM
Function: detact and transfer (not processing the info)
Sub-components (visual, auditory, …)
Duration: several seconds depends on the component
Capacity: infinite
Short-term memory store
Capacity: 7±2 chunks of information
Duration: 30 seconds
Requires rehearsal to transfer to LTM
Long-term memory store
Capacity: infinite
Duration: infinite
Multi-Store Model’s Strength
Lots of support evidences
Most influential memory model
Able to explain multiple observed phenomenon
Multi-Store Model’s Limitation
Too focus on the structure compared to process
Only one way direction for the information to flow (sensory → LTM) which is not true in many cases
Oversimplify:
More way for information to transfer
STM and LTM can be divided further
Serial Postion Effect
Participants can recall the first and last item on the list better than the one in the middle.
The items in the beginning already go to the longterm memory as it has been repeated too many time
The items in the end are still in the short-term memory
Aim
To investigate the serial position effect with and without interference from a filler activity.
Participants
46 army enlisted men
Method
Repeated Measured Design
Experiment
Procedure
Participants were read a series of 15-word lists and needed to recall the list of words in any order. They were to do this for 3 conditions (5 lists per condition → total of 15 lists is used) :
Recall immediately after
Recall after a 10 second filler activity
Recall after a 30 second filler activity
A filler activity could include counting backwards from a number; the point was to prevent rehearsal. Each participant went through all the conditions, completing 5 lists per condition (15 total). Conditions were randomized.
Result
Condition 1: show serial position effect
Remembers words at the start → primary effect
Remembers words at the end → recency effect
Condition 2:
Still remembers words at the start → primary effect preserved
No longer remembers words at the end → no recency effect
Conclusion
Since people intend to memorize the words, they repeat them in their head → words at the start were rehearsed multiple time → longterm memory → unaffect by the filler task
However the 30 seconds filler task remove word at the end from their short-term memory → unable to recall in the 2nd condition
Since only recency effect disappears → show that short term memory and long term memory are separated → supporting multi-store model
Strengths
All words are one syllable → easy to process by most participant → low participant variability → high construct validity
Large sample (240) → high population validity
Repeated measures design → low particpant variability → high internal validity
Free recall → high construct validity
Multiple lists: some words might be easier or harder to rememeber depends on participant emotional attach
Practice effect → affect the result
Limitations
The testing method (repeated word) is quite simple compared to the complexity of the memory → hard to generate to real life → low external validity → not a clear indicator for clear separation of the STM and LTM
Participants are all male → no diversity → low population validity
Boredom, fatigue can impact the result
Only 30 seconds → duration of STM can be longer → construct validity