3 The working memory model

Who invented the working memory model + provide date?

• Baddeley & Hitch 1974

Describe the working memory model.

• Concerned with ‘mental space’ that is active when we are temporarily storing & manipulating information

• Suggests that STM is a dynamic processor of different types of information using subcomponents co-ordinated by a centra; decision-making system

Describe central executive

• Monitors incoming data, focuses & divided our limited attention & allocates subsystems to tasks

• Determines how resources are allocated to other components

• Limited capacity & does not store information

• Modality-free: processes all types of information

Describe the phonological loop

• Deals with acoustic information & separated into:
  → Phonological store - stores words you hear/read

→ Articulatory process - allows maintenance rehearsal (Repeating sounds/words in a ‘loop’ to keep them in working memory whilst they’re needed & preserving order in which information arrived. 2 Seconds worth of information (Limited capacity))

Describe visuo-spacial sketchpad

• Introduced by Baddeley in 2003

• Stores visual and/or spacial information when required

• Limited capacity of about three/four objects

• Robert Logie (1995) subdivided the VSS into:

→ Visual cache - stores visual data

→ Inner scribe - Records the arrangement of objects in visual field

Describe the Episodic buffer

• Introduced by Baddeley in 2012

• Temporary store of information, integrating the visual, spacial & verbal information processed by other stores & maintaining a sense of time sequencing - recording events happening

• Storage component of central executive & has a limited capacity of about 4 chunks

• Links working memory to long-term memory & wider cognitive processes e.g perception

Evaluate - Clinical evidence & Counterpoint

• Support from Tim Shallice & Elizabeth Warrington (1970) case study of patient KF who after his brain injury, had poor STM ability for acoustic info but could process visual information just as well before injury

• KF’s phonological loop was damaged, but his visuo-spatial sketchpad was intact

• This finding strongly supports the existence of separate subsystems for visual & acoustic information as just his phonological loop had been damaged therefore the components are anatomically distinct

• Counterpoint: Unclear whether KF had other cognitive issues which may have affected his performance on memory tasks

• E.g his injury was caused by a motorcycle accident. Trauma may have affected cognitive performance quite apart from any brain injury

Evaluation - Neuroimaging evidence

• Evidence from brain scans for existence of subsystems in working memory

• Edward Smith & John Jonides (1997) used PET to show that tasks using the phonological loop were linked to activation in left temporal & frontal lobes, while tasks using visuo-spatial sketchpad were associated with activity in right parietal lobe, providing reliable & objective evidence for working memory’s subsystems

Evaluation - Nature of central executive

• One limitation is that there is a lack of clarity over the nature of central executive

• Baddeley (2003) said ‘the central executive is the most important but the least understood component of working memory

• The central executive needs to be more clearly specified than just being simply ‘attention’ → e.g some psychologists believe the central executive may consist of separate subcomponents

• This means that the CE is an unsatisfactory component & this challenges the integrity of the working memory model.

Evaluation - Baddeley Dual task performance

• Baddeley devised the dual task technique to test the idea of more than one component

• Participants completed either 1 visual & 1 verbal task at the same time or 2 of the same type of task at the same time

• Showed that participants had more difficulty doing two tasks that use the same component than doing two tasks that use different components. This was supporting evidence that the STM was not a unitary store but was made up of multiple components.