Memory - The Working Model of Memory

Memory - The Working Model of Memory

1. short term memory was divided in to several different components.

   • The Central Executive
     • directs attention to particular tasks. It 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).
   • Phonological Loop
     • This also has a very limited capacity. It stores a limited number of speech based sounds (acoustic coding) for brief periods. This component is subdivided into the phonological store and an articulatory process
   • Visuo-Spatial Sketch pad
     • this is used when you have to plan a spatial task. It involves holding visual and spatial information (visual coding) and capacity is limited to about 4 objects. It can be thought of as the inner eye.
   • Episodic Buffer
     • This enables the central executive to access information in the LTM it integrate it with information in the other systems. It helps create a mental episode of what is experienced and maintains a sense of time sequencing. Its capacity is limited to about 4 chunks and coding is modality free.

2. support for the working model of memory

   • Support for the WMM comes from dual task experiments. The model predicts that it will be harder to do 2 things at the same time if they are both visual tasks or both verbal tasks, because both will be using the same store at the same time. However, if you are doing 2 things at the same time but one is a visual task and one is a verbal task you should be able to do them as well simultaneously as you would separately, because they use different stores.
     • Baddeley. All participants were given a visual task (tracking a moving light with a pointer). They were then given another task to do at the same time. Imagining a hollow letter F and going round it saying whether each of the angles was inside or outside of the shape. Repeating words. Task i) impaired performance on the pointer task, but task ii) did not.
   • Cohen (1997) put participants in a brain scanner and asked them to carry out different tasks. When the central executive was working, 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. This suggests tasks using different parts of the WM use different parts of the brain.

3. Weaknesses for the Working Model of Memory

   • The 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 is too vague to suggest it is ‘attention’, and don’t think this actually explains its role adequately.
   • The model suggests there is a single central executive but there is evidence for several components. EVR had a cerebral tumour removed. He performed well on tests requiring reasoning, which suggested that his central executive was intact, but he had poor decision-making skills e.g. deciding where to eat) which suggests that his central executive was not wholly intact.