Working Memory Model - Baddeley and Hitch (1974)

Yo,

Baddeley and Hitch suggested that memory is comprised of different systems and these systems are involved when we use our memory (hence the term 'working memory'). There model had 3 systems: the central executive, the phonological loop, and the visuospatial sketchpad (VSSP).

The Central Executive:

This is a limited capacity (see overload below) system for general processing of information in memory. It was originally seen as a homunculus (a very small human) that guides the activity of the 2 slave systems (so called because they are not independent of the central executive) and how they function. It was also thought to be modality free - it can handle information in different forms (i.e. visual, sound, touch).

The Phonological Loop:

This is one of the slave systems that deals with the temporary storage of verbal information. Inside the phonological loop are 2 components - the rehearsal system and phonological store. The store can only hold a small amount of verbal information (which we will test in the lesson) for a few seconds, this duration can be increased by the rehearsal system (the inner voice, just like rehearsal in the MSM).

The Visuospatial sketchpad (VSSP):

This slave system deals with verbal AND spatial (i.e. the location or position of something) information. The VSSP can either process information directly (by looking at it) or getting visual information from LTM (i.e. remembering a friend's face). The VSSP maintains visual information, it allows up to observe the world and understand it by relying on visual information in LTM. There is a limited capacity to the VSSP, which we will investigate in the lesson.

Overload:

Working memory is seen as limited capacity because it can affected by distraction (someone talking to you whilst trying to remember a number), overload (trying to remember a list that is too long), and overwork (trying to perform complicated calculations in your mind). This has been demonstrated in dual task experiments (expt's that involved completing tasks that use either the same slave system, or 2 different slave systems) - ppts are asked to do 2 verbal tasks at the same time (i.e. repeat a string of numbers out loud whilst answering true or false questions)

BUT the WMM does explain why people can do well at dual task experiments. When asked to do a verbal and a spatial task at the same time, ppts performance is not as poor.