The Working Memory Model (WMM)

Question 1

The Working Memory Model – an overview

Answer 1

Baddeley and Hitch (1974) proposed an alternative model to explain the short-term memory.
They rejected Atkinson and Shiffrin’s ideas about STM being a unitary store; they argued that it was more complex than simply being a temporary store involved in transferring information to LTM.
They saw STM as an ‘active processor’, holding several pieces of information while they were being worked on.

They explained STM as consisting of 4 key stores/components:
The Central Executive (oversees the three ‘slave systems’)
The Visuo-Spatial Sketchpad
The Phonological Loop
The Episodic Buffer (added to the model in 2000)

Question 2

The Working Memory Model (WMM) – Revised- Baddeley and Hitch, 2000

Answer 2

(LOOK AT A DIAGRAM)

Question 3

Components of the Working Memory Model
Central Executive

Answer 3

The most important component

It controls attention i.e. it receives information from the sense organs (e.g. ears, eyes) and decides what to attend to (it filters incoming information)

It plays a key role in directing information to and processing information from the ‘slave systems’ and LTM

It is involved in problem solving and decision-making

It has a limited storage capacity, so attention is limited at times

Question 4

Components of the Working Memory Model
Phonological Loop (PL)

Answer 4

It processes speech-based sounds for brief periods
It has a limited capacity

It consists of two parts:
Phonological (Primary Acoustic) Store (inner ear) – stores
acoustically coded items e.g. words recently heard

Articulatory Control Process (inner voice) – allows sub-vocal repetition (rehearsal) of items stored in the phonological store

Question 5

Components of the Working Memory Model
Visuo-Spatial Sketchpad (VSS)

Answer 5

Stores/processes visual and spatial information (inner eye) and the relationships between them i.e. what items are and where they are located
It helps individuals to navigate around and interact with their environment
It manipulates mental images
It has a limited capacity

Visual Cache
Stores visual information about form and colour

Inner Scribe
Deals with spatial and movement information e.g. body movements
Rehearses and transfers information in the visual cache to the central executive

Question 6

Components of the Working Memory Model
Episodic Buffer

Answer 6

An additional temporary storage system
It binds together information from the different components into chunks/episodes, including information from LTM e.g. recalling a scene from a movie (visual and verbal information)
It has a limited capacity

Question 7

Key assumption of the WMM

Answer 7

Baddeley proposed that because the STM consists of several different components that are able to work independently of one another, that it is therefore possible to complete a visual and a verbal task simultaneously e.g. watching a film/TV, which would involve different slave systems.

Question 8

Coding and capacity
Central Executive

Answer 8

Coding
It processes information in all sensory forms

Capacity
Limited – it can only effectively cope with one strand of information at a time

Question 9

Coding and capacity
Phonological Loop

Answer 9

Coding
Acoustically – it deals with auditory information (sensory information in the form of sound)

Capacity
Limited

Question 10

Coding and capacity
Visuo-spatial sketchpad

Answer 10

Coding
Visually – information is coded and rehearsed through the use of mental pictures

Capacity
Limited

Question 11

Coding and capacity
Episodic Buffer

Answer 11

Coding
Capable of processing both visual and auditory information

Capacity
Can potentially hold more than each of the two slave systems

Question 12

One advantage of the Working Memory Model compared to the Multi-store Model of Memory is that……

Answer 12

…it suggests STM is an active processor rather than the unitary ‘stopping-off station’ version.
…it explains how it is easier to do two tasks that are different (e.g. verbal and visual) than two tasks that are similar (e.g. two verbal tasks).
Two similar tasks place too many demands on the same slave system (limited capacity), making it more difficult to process the information

Question 13

Baddeley et al. (1973)
Procedure

Answer 13

Procedure: Laboratory study – ‘dual-task technique/performance’
Ppts had to track a moving spot of light whilst either imagining the letter ‘F’ and classifying the angles (Yes = included bottom/top line of letter; No = if it did not) or completing a verbal task.
They therefore compared participants doing two visual tasks, against those doing a visual and a verbal task.

Question 14

Baddeley et al. (1973)
Findings

Answer 14

Participants found it more difficult to track the spot of light whilst classifying the angles of the letter ‘F’, because both tasks involved the visuo-spatial scratchpad, which has a limited capacity.
However, those doing the visual and verbal task found it less difficult to complete both tasks simultaneously, because they involved both the VSS and PL, therefore suggesting that the VSS is a separate slave system.

Question 15

:) Brain-damaged patients

Answer 15

K.F. – damage to phonological loop following a motorcycle accident led to difficulty in processing auditory information, but not visual information.
L.H. – performed better on spatial than visual imagery tasks, supporting the view that there are separate visual and spatial systems.

Question 16

What do these case studies therefore suggest?

Answer 16

They provide evidence for the existence of the two main slave systems in STM, as well as the sub-systems within the visuo-spatial sketchpad.

Question 17

Why might it be difficult to generalise the findings from these case studies?

Answer 17

The process of brain injury is traumatic, which may in itself change behaviour, causing a person to perform worse on certain tasks.
This therefore makes it difficult to generalise the findings to others because of the unique characteristics of each individual (they lack population validity).

Question 18

Further research evidence

Answer 18

D’Esposito et al found using MRI scans the prefrontal cortex was activated when verbal and spatial tasks were performed simultaneously but not when performed separately, suggesting the brain area indicates the working of the CE.

PET scans show that different areas of the brain are activated when doing verbal and visual tasks, which suggests that the phonological loop and visuo-spatial sketchpad are separate stores, as reflected in the biology of the brain.

PET scans have also shown activation in the left hemisphere of the brain with visual tasks and activation in the right hemisphere with spatial information, which supports the existence of the visual cache and inner scribe.

Question 19

:(Central Executive – a vague concept

Answer 19

There are problems in specifying the precise function of the central executive – it isn’t clear what it is or how it works.
Research into this [supposedly important] component is lacking.
Critics dispute the idea of a single central executive and instead argue that there are probably several components.
It is perhaps better understood as a component controlling the focus of attention rather than a memory store like the PL and VSS.

:(Working memory only concerns STM so it is not a comprehensive model of memory (as it does not include the SR or LTM).