The working memory model Flashcards
What is the working memory model about?
The working memory model (Baddely and Hitch) is an explanation of how one aspect of memory (short term memory) is organised and how its functions.
Describe the central executive?
The central executive has a supervisory role. It monitors incoming data, focuses and divides our limited attention and allocates slave system to tasks.
The CE has a very limited processing capacity and does not store information.
Describe the phonological loop?
One of the slave systems is the phonological loop. It deals with auditory information and preserves the order in which the information arrives. PL is subdivided into:
- The phonological store which stores the words you hear
- The articlatory process which allows maintenance rehearsal or words in loop to keep them in working memory while they are needed. The capacity of the loop is believed to be 2 seconds worth of what you can say.
Describe the visco spatial sketchpad?
The second slave system is the visco spatial sketchpad.
The VSS stores visual or spatial information when required. For example if you were asked to work out how may windows there are on your house you visualise.
It also has a limited capacity which according to Baddely is about 3 or 4 objects. Logie subdivided the VSS into:
- The visual cache which stores visual data
- The inner scribe which records the arrangements of objects in the visual field.
Describe the episodic buffer?
The third slave system is the episodic buffer. This was added to the model by Baddley in 2000. It is a temporary store for information, integrating the visual spatial, and verbal information processed by other stores and maintaining a sense of time sequencing- basically recording events that are happening. It can be seen as a storage component of the central executive and has limited capacity of about 4 chunks.
The episodic buffer links working memory long term memory and wider cognitive process such as perception.
Why is clinical evidence a strength?
One strength is support from a case study of patient KF.
After his brain injury, KF had poor STM ability for auditory information but could process visual information normally.
For instance his immediate recall of letters and digits was better when he read than when they were read to him. KF’s phonological loop was damaged but his visuo spatial sketchpad was intact.
This findings strongly supports the existence of separate visual and acoustic memory stores.
What is a counterpoint for that?
However it is unclear whether KF had other cognitive impairments which might have affected his performance on memory tasks.
For example his injury was caused by a motorcycle accident. The trauma involved may have affected his cognitive performance quite apart from his brain injury.
This challenges evidence that comes from clinical studies op people with brain injuries that may have been affected many different systems.
Why is dual task performance a strength?
Another strength is that studies of dual task performace support the separte existance of the visup spatial sketchpad.
When Baddeley et al’s participants carried out the visual and verbal task at the same time their performance on each was very similar to when they carried out that task separately.
But when both tasks were visual tasks performance on both declined substantially. This is because both visual tasks compete for the same slave subsystem, whereas there is no competition when performing a verbal and visual task together.
This shows there must be a separate slave system that processes visual input and one for verbal processing the PL
Why is nature of the central executive a limitation?
One limitation is that there is a lack of clarity over the nature of the central executive.
Baddeley himself recognised this when he said. ‘The central executive is the most important but the least understood component of working memory.
The CE needs to be more clearly specified than just being simply attention. For example some psychologist believe the CE may consist of separate sub components.
This means that the CE is an unsatisfactory component and this challenges the integrity of the WMM
