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ALAN BADDELEY AND GRAHAM HITCH (1974)
Suggests that memory is an active, multi-component
memory system.
Subsystems of working memory with temporarily
stores and manipulates information.
Working memory encodes the information into long
term memory (LTM) and retrieves the memory from
LTM
Indicates we are actively doing something with the
information. e.g memory holds words before we form
a sentence.
Holds all information for cognitive activities.
(planning, thinking, analysis)
Originally suggested that working
memory consisted of three separate
components that did not relate to each
other.
 Called “slave systems”:
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› Phonological loop
› Visuospatial sketchpad
› Central executive
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2000, Braddeley added a third slave
system: the episodic buffer.
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Phonological loop holds verbal information
Is an area of working memory that stores a
limited number of speech based and acoustic
sounds that are received from echoic memory
(Atkinson and Shiffrin) and/or LTM
Will hold for up to 2 seconds unless information
is rehearsed to prevent decay of memory.
Is at work when preparing a sentence, or
temporarily remembering a phone number.
Has two subsystems:
› Phonological store – inner ear
› Articulatory control system – inner voice
Phonological loop stores sounds we hear
for 1.5 - 2 seconds. These sounds will fade
unless taken by the articulatory control
system.
 The articulatory control system holds
sound we want to keep, or that we are
preparing to speak. Will hold for 2
seconds.
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The visuospatial sketchpad (VS) is one of
two passive slave systems in Baddeley &
Hitch’s (1986) model of working memory
 Visual information refers to what things
appear to look like.
 The VS provides temporary storage and
manipulation of visual and spatial
information held in the long-term
memory (LTM).
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The information stored is maintained by
spatial rehearsal
 The VS plays an important role in helping
us keep track of where we are in relation
to other objects as we move through our
environment.
 Evidence suggests that working memory
uses two different systems for dealing with
visual and verbal information.
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A visual processing task and a verbal
processing task can be performed at the
same time. It is more difficult to perform
two visual tasks at the same time
because they interfere with each other
and performance is reduced.
 The same applies to performing two
verbal tasks at the same time. This
supports the view that the phonological
loop and the sketchpad are separate
systems within working memory.
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As we move around, our position in
relation to objects is constantly changing
and it is important that we can update
this information.
› E.g., being aware of where we are in relation
to desks, chairs and tables when we are
walking around a classroom means that we
don't bump into things too often!
Briefly stores limited amounts of
information from the phonological loop
and visuospatial sketchpad with
information taken from LTM.
 The information taken from the two is
integrated into an episode to make
sense.
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Central executive monitors, coordinates and
integrates information from the phonological
loop, visuospatial and episodic buffer.
 It controls:
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The flow of information from its slave systems which
plays a major role in attention
Which items move in and out of short term memory
(STM) by deciding which information arriving from
sensory will be attended to
The retrieval process from long term memory (LTM)
When we multi-task
Two key characteristics of Atkinson and
Shriffin’s multi-store model that originally
defined STM – limited capacity and limited
duration – are present in the working
memory model.
 But the Baddeley and Hitch model
accounts for evidence that STM handles a
greater variety of functions and depends
on more complicated processes than
previously thought.
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