Working Memory Model

• The working model of memory is an explanation of how short-term

  memory is organised and how it works (Baddeley & Hitch, 1974). The WMM is concerned with the part of the mind that is active when we are temporarily storing and manipulating information from the environment.
• Central executive

  • Attentional process that monitors incoming data.
  • It is the ‘boss’ of working memory as it decides how to process the incoming information by allocating relevant slave systems to tasks.
  • It has a very limited processing capacity.
• Phonological loop

  • The phonological loop is one of the slave systems.
  • It processes auditory information (i.e. it’s coding is acoustic) and preserves the order in which the information arrives.

  The phonological loop has two sub-divisions:

  • The phonological store – stores the words you hear.
  • The articulatory process – allows for maintenance rehearsal 
  • The capacity of this loop is two seconds of what you can say.
• Visuo-spatial sketchpad

  • Another one of the slave systems
  • Stores visual and/or spatial information when required
  • The capacity is limited to 3-4 objects (Baddeley, 2003)

  Logie (1995) subdivided the visuo-spatial sketchpad:

  • The visual cache – stores visual data.
  • The inner scribe – records the arrangement of objects in the visual field.
• Episodic buffer

  • Third slave system added to the model by Baddeley (2000)
  • Seen as the storage component of the central executive.
  • It is a temporary store for information, integrating the visual, spatial and verbal information processes by the other stores and maintaining a sense of time sequencing i.e. recording events (episodes) that are happening.
  • The episodic buffer links working memory to long-term memory and wider cognitive processes such as perception.
  • It has a limited capacity of approx. 4 chunks (Baddeley, 2012).
• Supports:

  • Clinical evidence

  Shallice and Warrington (1970) case study: KF had

  amnesia. KF had poor STM ability for verbal info but could process visual info normally (he had difficulty with sounds not letters and digits) suggesting that just PL was damaged and other areas intact.

  • Scientific evidence 

  Braver et al. (1997) gave participants tasks that involved the CE while they were having a brain scan. The researchers found greater activity in the left PFC. The activity in this area increased as the task became harder – makes sense in WMM: demands on CE increase, has to work harder.
• Limitations:

  • Central executive has a lack of clarity. 

  The central executive needs to be more clearly specified than just being simply an ‘attentional process’ - some psychologists believe it may even consist of separate components.