4. The Working Memory Model

Baddeley and Hitch (1974)

WMM

central executive

directs attention to particular tasks

very limited capacity

phonological loop

deals with auditory information and preserves the order of information

capacity of 2 seconds (word length efect)

phonological store

inner ear

holds words recently heard

articulatory process

inner voice

holds information via subvocal repetition

visuo-spatial sketchpad

inner eye

processes visual and spatially coded information

visual cache

passive store of form and colour

inner scribe

active store holding the arrangement of objects in a 3D space

Logie (1995)

suggested the visuo-spatial sketchpad can be divided into visual cache and articulatory process

episodic buffer

added to WMM in 2000

general store to hold and integrate information from the CE, PL, VSS, and LTM

one strength is research support for the PL and VSS as separate

Baddeley (1975) asked pps to perform two visual tasks or a visual and verbal task. found that performance was better when the tasks were not using the same processing.

dual task performance

suggests the VSS and PL exist as separate system

one strength is evidence from brain-damaged patients

Shallice and Warrington (1970) studied a man called KF and found that KF had a selective impairment to his verbal STM but the visual functioning of his STM was not affected

suggests the PL and VSS subsystems are separate processes located in separate brain regions

one limitation is the problems associated with using case studies as research support

brain injury is traumatic which may itself change behaviour so that a person performs worse on certain tasks

individuals with brain damage may have other difficulties such as difficulties paying attention and therefore underperform on tasks

case studies are of unique individuals (idiographic) and cannot be generalised to the population

therefore the WMM lacks validity as some of the key research that supports it comes from case studies

one limitation is some psychologists criticise the CE for being too vague

the CE appears to only allocate resources and is the same as attention

critics believe the notion of a single CE is wrong and that there are several components

Eslinger and Damasio (1985) studied EVR (who had a cerebral tumour removed). he performed well on tests requiring reasoning, suggesting his CE was still intact. however he had poor decision-making skills, suggesting his CE was not intact

therefore the notion of CE that Baddeley and Hitch suggested is unsatisfactory because it appears more complex than what was suggested