Working memory model

• Working memory model

  Baddeley and Hitch (1974)
• The episodic buffer

  • The EB is regarded as an extra temporary stores for the CE.
  • It integrates visual, spatial and verbal information, maintaining time sequencing.
  • It links the WM to our LTM.
  • It is limited to 4 chunks.
• The Visuo-spatial sketchpad

  • Temporary storage system for visual and spatial information which also has two components:
  • The inner scribe: stores information about the physical relationship of items (spatial coding)
  • The visual cache: stores visual data about form and colour. (visual coding)
• The phonological loop

  • It is a temporary storage system for auditory information and preserves the order in which information arrives. Coding is acoustic and capacity is about 2 seconds
  • It is subdivided into two components:
  • The phonological store (inner ear) : Stores the words recently heard
  • The articulatory process (inner voice) : Allows maintenance rehearsal (sub-vocal repetition of information) 
• The working memory model-

  • is an explanation of how one aspect of memory, STM, is organised and how it functions.
  • It becomes active when we are temporarily storing and manipulating information.
  • The model consists of 4 main components, each of which differs in its coding and capacity
• The central executive

  • The CE is the ‘boss’ of the WMM.
  • It controls attention and directs information to the two slave systems: the phonological loop and visuo-spatial sketchpad.
  • The central executive has a limited capacity but can process information from any sensory modality.
• coding, capacity and function

  
• WMM image

  
• One strength of the model is support form clinical evidence.

  For example, shallice and warrington (1970) studied patient KF who had brain injury. Hi STM for auditory information was poor (damaged phonological loop) but he could process visual information normally (intact visuo-spatial sketch pad). This supports the WMM view that there are separate visual and acoustic memory stores
• one strength of the model is support from clinical evidence: counterpoint

  KF may have had other impairments which explained poor memory performance, apart from damage to his phonological loop. this challenges evidence from clinical studies of brain injury
• another strength is that dual task performance studies support the visuo-spatial sketchpad 


  Baddaleys (1975) participants found it harder to carry out 2 visual tasks at the same time than do a verbal and visual task together. this was the same for 2 verbal tasks. this is because both visual tasks compete for the same subsystem. there is no competition with a verbal and visual task. therefore there must be a separate subsystem that processes visual input (visuo-spatial sketchpad) and also a separate system for verbal processes (phonological loop)
• one limitation is a lack of clarity over the central executive

  Baddeley (2003) said the central executive was the most important but the lease understood component of working memory. there must be more to the central executive than just being ’attention’ e.g. its made up of separate subsystems. therefore the central executive is an unsatisfactory component and this challenges the integrity of the model