The Working Memory Model

What is the working memory model?

A representation of STM, it suggests that STM is a dynamic processor of different types of information using subunits co-ordinated by a central decision making system.

Who proposed the WMM?

Baddley and Hitch (1974).

What is the WMM concerned with?

The ‘mental space‘ that is active when we are temporarily storing and manipulating information.

What does the WMM consist of?

Four main components, each of which is qualitatively different, especially in terms of coding and capacity.

What are the four components of the WMM?

• Central executive

• Phonological loop.

• Visuo-spacial sketchpad.

• Episodic buffer.

What is the central executive?

The component of the WMM that co-ordinates that activities of the three subsystems in memory. It also allocates processing resources to those activities.

What is the capacity of the central executive?

It is very limited and does not store information.

What is the phonological loop?

The component of the WMM that processes information in terms of sound. This includes both written and spoken material.

What is the phonological loop divided into?

• Phonological store.

• Articulatory process.

What does the phonological store do?

Stores the words you hear.

What does the articulatory process do?

It allows maintenance rehearsal (repeating sounds or words in a ‘loop‘ to keep them in the working memory while they are needed).

What is the capacity of the articulatory process?

The capacity is believed to be two seconds worth of what you can say.

What is the coding in the phonological loop?

Coding is acoustic.

What does the phonological loop preserve?

The order in which the information arrives.

What is the visuo-spacial sketchpad?

Thr component of the WMM that processes visual and spacial information ina mental space often called the ‘inner eye‘.

What is the capacity of the visuo-spacial sketchpad?

Very limited; about three or four objects.

What is the visuo-spacial sketchpad divided into?

• Visual cache.

• Inner scribe.

What is the role of the visual cache?

It stores visual data.

What is the role of the inner scribe?

It records the arrangement of object in the visual field.

What is the episodic buffer?

The component of the WMM that brings together material from the other subsystems into a single memory rather than seperate strands. It also provides a bridge between working memory and long-term memory.

When was the episodic buffer added?

In 2000, by Baddley.

What element of the WMM links working memory to long-term memory and wider cognitive processes, such as deception?

The episodic buffer.

What are the strengths of the WMM?

• Clinical studies.

• Dual task performance studies.

How do clinical studies support the WMM?

The case study of KF: after his brain injury, he had poor STM ability for auditory information but could process visual information normally. His immediate recall of letters and digits were better when he read them then when they were read out to him. KF’s phonological loop was damaged but his visuo-spacial sketchpad was intact.

What does the findings of KF’s case study support?

The existence of seperate visual and acoustic memory stores.

What is the counterpoint to the support of clinical studies?

It is unclear whether KF had other cognitive impairments apart from the dmage to his PL which might have affected his performance on memory tasks. For examle, his injury was caused by a motorcycle accident, the trauma involved may have affected his cognitive performance quite apart from any brain injury.

What does the counterpoint to the clinical sudies challenge?

Evidence that comes from clinical studies as people with brain injuries that may have affected different systems.

How is dual task performance a strength of the WMM?

When Baddley’s participants carried out a visual and verbal task at the same time, their performance on each was similar to when they were carried out the tasks separately. When both tasks were visual or verbal, performance on both declined substantially. This is because both visual tasks compete for the same subsystem, while there is no competition when performing a verbal and visual task together.

What does evidence from dual task performance show?

There must be a seperate subsystem that processes visual and verbal imput.

What is the limitation of the WMM?

• The nature of the central executive.

How is the nature of the central executive a limitation of the working memory model?

There is a lack of clarity over the CE; Baddley said ‘the central executive is the most important but the least understood component of working memory.‘ The CE nees to be more clearly specified than beiing simply ‘attention‘. Some psychologists even believe that it consists of seperate subcomponents.

What does the uncertainty surrounding the central executive mean?

That the CE is an unsatisfactory component, and this chalenges the integrity of the WMM.