Describe Baddeley and Hitch's Working Memory Model. Explain What Evidence Supports It

In this essay I will be describing the Baddeley-Hitch working memory model. The working model is one of the most researched upon model especially in the UK. It has been used to account for human cognitive functions in situations like how human are able to perform mathematical equations in their mind, learning language, reading, able to visualise etc.

Baddeley and Hitch (1974) and Baddeley (1986) was the first to proposed the working memory model which replaced the original concept of ‘multi-store model' developed by Atkinson and Shiffrin (1968). They claimed ‘memory as having three major components; sensory memory, working (short –term) memory and long-term memory' [1]. ‘Sensory memory' briefly holds incoming sensory information, if attention is acted upon it then it would be sent to the ‘working (short-term) memory', if rehearsal of the information is taken place here then the information is encoded to the ‘long-term memory' where it will remain and can be retrieved when needed be.

The working memory is the ‘heart of the Baddeley-Hitch model, a system that consists of two short-term stores and a control system, three important characteristics differentiate this model from the Atkinson-Shiffrin model' [2]. The three components of the Baddeley-Hitch model is; central executive (acting as a control system), phonological loop and the visuo-spatial sketchpad (which both acts as short-term stores) these three components of this particular model work together to provide a much more ‘comprehensive workspace for cognitive activity' [2].

Central executive is the component that most strongly differentiates the idea of working memory from the earlier conceptions of the ‘short term memory'. D'Esposito et al. (1995) used fMRI to identify the brain regions that are involved in dual-task performances to see where the central executive is located, which was found in the frontal cortex of the human brain. As its role of being the ‘key component' it determines when the information is deposited in the storage buffers and which buffer the information goes to (phonological loop for verbal information or visuo-spatial sketchpad for visual). It also allows information to integrate and coordinate between the two buffers, and most importantly the mechanism by which information held in the buffers can be inspected, transformed and cognitively manipulated [2].

Baddeley (1996) claimed that if damage were to occur in the frontal lobe of the cortex it can cause impairments to the central executive functioning. Patients that suffer from damage to their frontal cortex are said to have ‘dysexecutive syndrome', this has enabled psychologists to identify the major functions of the central executive. Baddeley (1996) also supported by Smith and Jonides (1999) identified the following functions [3];

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