An explanation of how STM is organised and how it functions
Concerned with the 'mentalspace' that is active when we are temporarily storing and manipulating information
The model consists of four main components, each of which is qualitatively different especially in terms of coding and capacity
Centralexecutive
'Supervisory' role
Monitors incoming data, focuses and divides our limited attention and allocates subsystems to tasks
Limited processing capacity and does not store information
Codes depending on the sense
Phonological loop
Deals with auditory information and codes acoustically
Preserves the order in which information arrives
Limited capacity of 2 seconds
Subdivided into a phonological store (stores the words you hear) and articulatoryprocess (allows maintenance rehearsal and a 2 second capacity worth of what you can say)
Visuo-spatial sketchpad
Stores iconic memory when required
Has a limited capacity of 3-4 items
Codes iconically
Subdivided into visual cache (stores visual data) and inner scribe (records the arrangement of objects in the visual field)
Episodic buffer
Temporary store for info integrating the visual, spatial and verbal info processed by other stores and maintaining a sense of time-sequencing recorded events
Can be seen as the storage component of the CE
Codes depending on the sense
Limited capacity of 4 items
Links working memory to LTM and perception
Strength - case studies/clinical evidence
Shallice and Warrington study of patient KF
After his brain injury, KF had poor STM ability for auditory information but could process visual information normally
Phonologicalloop was damaged but his visuo-spatialsketchpad remained intact
Supports the idea of separate subsystems within the WMM
Counterpoint - did KF have other cognitive impairments?
If there is, they might have affected his performance on memory tasks
His injury was caused by a motorcycle accident and the trauma involved may have affected his cognitive performance
Strength - studies of dual task performance
Supports separate existence of the VSS
When Baddely's pps carried out a visual and verbal task at the same time their performance on each was similar to when carried out separetely
When both tasks were visual or both verbal, performance on both declined substantially due to both tasks competing for the same subsystem
Shows support for seperate subsytems
Limitation - lack of clarity over the nature of the CE
Baddely recognised this himself when he said 'The central executive is the most important but leastunderstood component of working memory'
It needs to be more clearly specified than just simply being 'attention' - some psychologists believe the CE may consist of separate subcomponents