Working Memory Model

• What are the different components of the Working Memory model (1974)?

  1. The central executive
  2. Phonological Loop
  3. Visio-spatial Sketch pad
  4. Episodic buffer

  
• Describe the central executive of the Working Memory Model:

  • most important part of the WMM
  • directs attention to particular tasks
  • has a very limited capacity and so can attend to a limited number of things at any time, but can code information from any type of source (coding is modality free - not one way in which information is processed)
• Describe the Phonological Loop of the Working Memory Model:

  • very limited capacity - stores a limited number of speech-based sounds (acoustic coding) for brief periods (approximately 2 secs)
  • this component is divided into the phonological store (holds the words you hear, like an inner ear) and an articulatory process (silently repeating words you hear, like an inner voice)
• Describe the Visuo-spatial Sketch pad of the Working Memory Model:

  • used when you have to plan a spatial task (remembering the relationships among objects in space)
  • involves holding visual and spatial information (visual coding) and capacity is limited to about 4 objects
  • can be thought of as the inner eye

  1. visual cache - stores information about form and colour
  2. inner scribe - stores the arrangement of objects in the inner field
• Describe the Episodic buffer (additional component) of the Working Memory Model:

  • enables the central executive to access information in the LTM and integrate it with information in the other systems
  • helps create a mental episode of what is experienced and maintains a sense of time sequencing
  • capacity is limited to about 4 chunks and coding is modality free
• What are the strengths of the Working Memory Model? (part 1)

  • Dual task experiments

  —> model predicts that it’ll be harder to do 2 things at the same time if they’re both visual/verbal tasks because both will be using the same store at the same time

  —> however if you’re doing 2 things at the same time but one is visual and one is verbal, you should be able to do them as well as you would simultaneously as you would separately as they’re different stores

  • This support came from an experiment by Baddeley **see image below

  
• What are the strengths of the Working Memory Model? (part 2)

  • Brain scans

  —> Cohen (1997) put participants in an MRI brain scanner and asked them to carry out different tasks. When the central executive was working (tasks e.g. the encoding, manipulation and retrieval of information) there was activity in the frontal lobe (prefrontal cortex) of the brain. The occipital lobe of the brain was active when a task was visual.

  —> suggests tasks using different parts of the WM use different parts of the brain (supports the model)
• What are the limitations of the Working Memory Model? (part 1)

  • Central executive is a very important part of the model, but the model doesn’t give enough information on how it allocates resources
  • some psychologists feel it’s too vague to suggest it’s ‘attention’ and don’t think this actually explains its role adequately
• What are the limitations of the Working Memory Model? (part 2)

  • Opposing evidence for several components rather than one single central executive

  —> supporting evidence:

  • EVR had a cerebral brain tumour removed - he performed well on tests requiring reasoning, suggesting his central executive was intact, but had poor decision-making skills e.g. deciding where to eat, suggesting his central executive was not wholly intact
  • This suggests the central executive may be more complex than a single entity as originally proposed by Baddeley and Hitch