Miller (1956) - Ptps were read a
sequence of numbers in trails eg
trail 1 - 6, trail 2 - 78 etc and after
each trail was read by the
researcher the ptp had to recal the
number or numbers. He called this
'chunking' and found that between
5 and 9 'chunks' could be
contained within the STM.
Peterson & Peterson (1959) -
Gave their ptps nonsense
trigrams (IQX) and then got them
to count backwards from a 3
diget number for between 3-18
seconds. About 90 per cent of
the ptps recalled the trigram
after 3 seconds but only around
5 per cent recalled the trigram
after 18 seconds, suggesting
that STM duration is around
20-30 seconds.
Baddeley (1966) - Ptps had to recall
lists of semantically similar words
(big,grand,large) , semantically
dissimilar words (tree,donkey,car),
acoustically similar words
(cat,bat,hat) and acoustically
dissimilar words (frog,sock,hair). He
found that ptps given acoustically
similar perform the worst with 10 per
cent recall.
LTM
Bahrick (1975) - showed 400 ptps aged
17-74 a set of photos and a list of names,
some were old school friends and asked
them to identify their friends in the photos.
Those who left school in the last 15 years
recalled 90 per cent of faces and names,
while those who left school 48 years ago recalled
80 per cent of names and 70 per cent
faces, suggesting that memory for faces in
long lasting.
Multi Store Model of Memory
Developed by Atkinson & Shiffrin (1968)
explains how information flows from one
storage system to another, with three
permanent structures in memory: sensory
memory, short- term memory and long- term
memory each stage differs in terms of
capacity, duration and encoding.
You recieve information
through your senses (touch,
taste, sight, smell, sound).
This information then goes
into your sensory store which
you will then put into your
short term memory (and
forget it) or your long term
memory whether if the
information is important or
not. Before it goes into your
long term memory your
rehearse it, after that you
retrieve the information from
your STM to rehearse it for
you LTM.
Baddeley (1996) found that the STM encodes information
acoustically and the LTM encodes information semantically.
This supports the multi store model as it shows that the STM
and LTM are seperate stores. This lacks ecological validity
and therefore STM & LTM encoding could be more complex.
Glanzer & Conitz (1996) found that when recalling lists of words
ptps recalled at the beggining (primary effect) and at the end of the
list this supports the multi-store model as ptp used rehearsak for
the first few words in the list and put them into their LTM as the
model predicts. It also shows the words reaclled at the end of the
list were still in the STM as they last in this store for a duration of
approx 18 seconds so ptps reaclled them. This research also
lacks ecological validity because it uses lists of words most
memories are not list of words, they use emotons etc.
Working Memory Model
Central Execeutive - This is the
most important component in the
model and its responsible for
monitoring and coordinating the
operation of the slave systems. It is
flexible in that it can process
information from any modelity and
also has some storage capacity
although it is very limited. It seems
to play a major role in attention,
planning and in synthesizing
information, not only from slave
systems but the LTM.
The Phonological Loop- This component stores a limited number of sounds for brief
periods and it can be thought of as an inner ear. It is thought to consist of two
components. One component is the phonological store (inner ear) that allows
acoustically coded items to be stored for a brief period, The other component is the
articulatory control system (the inner voice) that allows subvocal repitition of the items
stored int the phonological store.
The Visuo- Spactical Sketchpad - This
stores visual and spactical information
and can be thought of as an inner eye.
Like the phonological loop it has limited
capacity but the limits of the two systems
are independent. In other words, it is
possible for example, to rehearse a set of
digets in the phonological loop while
simultaneously making decisions about
the spactical layout of a set of letters in
the visuo spactical sketchpad.
Episodic
Buffer - Is a
tempory store
which holds
information for
a few seconds
while we
process it.