CODING, CAPACITY, DURATION
1. STM- limited capacity memory store, coding mainly acoustic, capacity
between 5 and 9 items, duration about 18 seconds.
2. LTM- permanent memory store, coding mainly semantic, capacity
unlimited, duration up to a lifetime.
3. Coding- the format in which information is stored in various memory
stores/ process of converting information between different forms.
4. Capacity- amount of information held in a memory store.
5. Duration- the length of time information can be held in memory.
6. RESEARCH ON CODING- BADDELEY. GAVE FOUR DIFFERENT groups of
participants different lists of words to remember (acoustically similar,
acoustically dissimilar, semantically similar, semantically dissimilar.) when
asked to recall IMMEDIATELY from STM, they did worse on acoustically
similar. When asked to recall after time interval of 20 mins, did worse on
semantically similar. Information is coded acoustically in STM (similar
sounding info conflicted with each other) AND semantically in LTM (words
with similar meaning conflicted with each other).
7. STRENGTH- made a clear difference between two memory stores. The idea
that in STM mainly coded acoustically and LTM mostly coded semantically
has stood test of time and was an important step in understanding memory
which led to MSM.
8. Limitation- used artificial stimuli rather than meaningful material. Lists of
words had no meaning to p’s so we can’t generalise this to everyday life.
People process meaningful information using semantic coding even for
STM. Limited application.
9. RESEARCH ON CAPACITY- JACOBS found out mean capacity of STM is 9.3.
used digit span- participant recalls 4 digits then 5 and so on. MILLER- made
the observation that things come in sevens: 7 days of week, 7 notes on a
music scale. Capacity of STM is about 7 items, +/- 2. We chunk information
together to remember it.
10. STRENGTH- JACOBS- very old study, confounding variables as p’s were
distracted during testing of digit span. Another controlled study was
conducted, and his findings were confirmed. It is valid. His study has been
replicated.
, 11.LIMITATION- MILLER- overestimated STM CAPACITY. Research was
conducted and concluded that capacity is 4 +/-1. Lower end of miller (5) is
more appropriate.
12.RESEARCH ON DURATION STM- PETERSON AND PETERSON- 24 Students in
8 trials, had to remember consonant syllables and 3-digit number. At the
same time, they had to count back from this number until told to stop at
different time intervals on each trial to prevent rehearsal. After 3 seconds
recall was 80%, after 18 seconds it was 3%. Without rehearsal, STM has a
very short duration.
13.RESEARCH ON DURATION LTM- BAHRICK ET AL- studied 392 american
participants aged 17-74, obtained yearbooks. They had to do photo
recognition test and free recall of the names of people in their class. After
15 years- photo recognition accuracy= 90%, free recall=60%. After 48 years-
photo recognition= 70%, free recall= 30%. LTM may last up to a lifetime.
14.STRENGTH- BAHRICK ET AL- high external validity. Used meaningful
material. When studies were conducted with meaningless pictures, recall
rates were lower. It’s a real estimate.
15.LIMITATION- PETERSON AND PETERSON- low external validity. Although
material wasn’t completely irrelevant as we sometimes remember this
every day, consonant syllables cannot be applied as this does not reflect
everyday memory activities.
MULTI STORE MODEL OF MEMORY
1. MSM- a representation of how memory works in terms of 3 stores: sensory
register, short term memory, long term memory. Describes how
information is transferred between stores and what makes some memories
last, and others lost.
2. SENSORY REGISTER- the memory store for our 5 senses. All stimuli from
environment passes into SR. Coding in the iconic store is VISUAL in echoic is
ACOUSTIC. Very HIGH CAPACITY. (millions of receptors) the duration is
short (less than ½ a second.) if you pay attention to the information it
passes further into the memory system.
3. STM- limited capacity store (5 and 9 items), duration 18 seconds unless
rehearsed, coding mainly acoustic. Maintenance rehearsal- repeating of
information over and over again, if this occurs information stays in the STM
and prolonged rehearsal- passes into LTM.
4. LTM- permanent memory store, duration up to a lifetime, capacity
unlimited, coding mainly semantic. For information that has been
1. STM- limited capacity memory store, coding mainly acoustic, capacity
between 5 and 9 items, duration about 18 seconds.
2. LTM- permanent memory store, coding mainly semantic, capacity
unlimited, duration up to a lifetime.
3. Coding- the format in which information is stored in various memory
stores/ process of converting information between different forms.
4. Capacity- amount of information held in a memory store.
5. Duration- the length of time information can be held in memory.
6. RESEARCH ON CODING- BADDELEY. GAVE FOUR DIFFERENT groups of
participants different lists of words to remember (acoustically similar,
acoustically dissimilar, semantically similar, semantically dissimilar.) when
asked to recall IMMEDIATELY from STM, they did worse on acoustically
similar. When asked to recall after time interval of 20 mins, did worse on
semantically similar. Information is coded acoustically in STM (similar
sounding info conflicted with each other) AND semantically in LTM (words
with similar meaning conflicted with each other).
7. STRENGTH- made a clear difference between two memory stores. The idea
that in STM mainly coded acoustically and LTM mostly coded semantically
has stood test of time and was an important step in understanding memory
which led to MSM.
8. Limitation- used artificial stimuli rather than meaningful material. Lists of
words had no meaning to p’s so we can’t generalise this to everyday life.
People process meaningful information using semantic coding even for
STM. Limited application.
9. RESEARCH ON CAPACITY- JACOBS found out mean capacity of STM is 9.3.
used digit span- participant recalls 4 digits then 5 and so on. MILLER- made
the observation that things come in sevens: 7 days of week, 7 notes on a
music scale. Capacity of STM is about 7 items, +/- 2. We chunk information
together to remember it.
10. STRENGTH- JACOBS- very old study, confounding variables as p’s were
distracted during testing of digit span. Another controlled study was
conducted, and his findings were confirmed. It is valid. His study has been
replicated.
, 11.LIMITATION- MILLER- overestimated STM CAPACITY. Research was
conducted and concluded that capacity is 4 +/-1. Lower end of miller (5) is
more appropriate.
12.RESEARCH ON DURATION STM- PETERSON AND PETERSON- 24 Students in
8 trials, had to remember consonant syllables and 3-digit number. At the
same time, they had to count back from this number until told to stop at
different time intervals on each trial to prevent rehearsal. After 3 seconds
recall was 80%, after 18 seconds it was 3%. Without rehearsal, STM has a
very short duration.
13.RESEARCH ON DURATION LTM- BAHRICK ET AL- studied 392 american
participants aged 17-74, obtained yearbooks. They had to do photo
recognition test and free recall of the names of people in their class. After
15 years- photo recognition accuracy= 90%, free recall=60%. After 48 years-
photo recognition= 70%, free recall= 30%. LTM may last up to a lifetime.
14.STRENGTH- BAHRICK ET AL- high external validity. Used meaningful
material. When studies were conducted with meaningless pictures, recall
rates were lower. It’s a real estimate.
15.LIMITATION- PETERSON AND PETERSON- low external validity. Although
material wasn’t completely irrelevant as we sometimes remember this
every day, consonant syllables cannot be applied as this does not reflect
everyday memory activities.
MULTI STORE MODEL OF MEMORY
1. MSM- a representation of how memory works in terms of 3 stores: sensory
register, short term memory, long term memory. Describes how
information is transferred between stores and what makes some memories
last, and others lost.
2. SENSORY REGISTER- the memory store for our 5 senses. All stimuli from
environment passes into SR. Coding in the iconic store is VISUAL in echoic is
ACOUSTIC. Very HIGH CAPACITY. (millions of receptors) the duration is
short (less than ½ a second.) if you pay attention to the information it
passes further into the memory system.
3. STM- limited capacity store (5 and 9 items), duration 18 seconds unless
rehearsed, coding mainly acoustic. Maintenance rehearsal- repeating of
information over and over again, if this occurs information stays in the STM
and prolonged rehearsal- passes into LTM.
4. LTM- permanent memory store, duration up to a lifetime, capacity
unlimited, coding mainly semantic. For information that has been
