The Working Memory Model
Baddely and Hitch (1974) suggested the idea of the Working Memory Model to replace the concept of a unitary STM. It proposes a multi-component, flexible system concerned with active processing and short term storage of information.
The central executive is involved in problem solving and decision making.
- Controls attention and plays a major role in planning and synthesising information from other systems and LTM.
- Flexible, can process information from any modality.
- limited storage capacity so can attend to a limited number of things at a time.
Stores a limited number of speech-based sound for brief periods.
It consists of two components:
- Phonological Store (inner ear) - allows acoustically coded items to be stored.
- Articulatory Control Process ( inner voice) - allows sub-vocal repetition of items that are stored in the phonological store. Articulatory suppression: repeating an irrelevant sound that is irrelevant to the task. This prevents the phonological loop from retaining any more information.
In Baddely et al.'s word-length studies, when participants were asked to repeat an irrelevant sound, word-length effect disappeared - articulatory suppression.
Visuo-Spatial Scratch Pad (inner eye)
Stores visual and spatial information. It sets up and manipulates mental images.
Baddely et al. gave participants a simple tracking task (holding a pointer in contact with a moving spot of light) while they performed an imagery task. Participants found it very difficult to do these two tasks at the same time.
Integrates and manipulates material in the working memory.
- Limited capacity depending on executive processing.
- Integrates information from different sources into chunks or episodes.
- Integrates material from LTM.
Strengths and Weaknesses of the Working Memory Mod
- Explains our ability to carry out tasks like mental arithmetic.
- Evidence supporting phonological loop.
- Evidence supporting the visuo-spatial scratch pad.
- Still expanding.
- Little information is known about the central executive.
- No explanation to how we remember other senses.