Working Memory

Baddeley and Hitch (1974)

Working Memory

• Baddeley and Hitch (1974)– Believed that the STM store in the Multistore

Model was too simplistic• STM not a passive store

– Actively manipulates information

• Working Memory is complex and consists of several components

Working Memory

Visuo-spatialSketchpad

Phonological Loop

EpisodicBuffer

CentralExecutive

Articulatory Control System

Phonological Store

Working Memory Components

• Central Executive– This component controls attention and coordinates

the actions of the other components

– It can briefly store information, but has a limited capacity

– It is modality free• This means it can store information in any sense modality

– Considered the most important part of working memory

Working Memory Components

• Phonological Loop– Consists of two parts

• Articulatory Control System– Rehearses information verbally

– Capacity based on time

– “The Inner Voice”

• Phonological Store– Sound based storage

– Decays after 2 seconds

– “The Inner Ear”

– Receives input from the ears or acoustic information from LTM

Working Memory Components

• Visuospatial Sketchpad– Stores visual information

– Used to manipulate visual information

– Input from the eyes or visual information from LTM

Working Memory Components

• Episodic Buffer– Episodic buffer not part of original model –

recently added (Baddeley, 2000)

– Holds information from all modalities

– Binds them with information about time (ordering)

– Strong links to LTM

Evaluation of Working Memory

• Strengths– High in Face Validity

• This means that the model seems plausible– In this case, it seems plausible because it fits with everyday

experience of manipulating information when solving problems

» Views STM as a dynamic process rather than a static store

Evaluation of Working Memory• E.g., Baddeley (1997) suggests that mentally

counting the number of windows in your house (or flat) demonstrates the operations of working memory

–Normally a person will imagine each room in turn, forming a mental image of each window (Visuo-spatial sketchpad), they will count using the phonological loop to rehearse the numbers and this will all be coordinated by the Central Executive.

Evaluation of Working Memory

• Another advantage of the Working Memory model is that verbal rehearsal is not necessary for all types of information – just verbal strings - this fits better with our everyday experience– E.g., events are processed by the episodic

buffer

Evaluation of Working Memory

• Empirical Evidence– Memory Span

• Baddeley (1975)– Memory span for visually presented one-syllable words

greater than for polysyllabic words

» Suggests that articulatory loop able to hold only a limited number of syllable chunks

Evaluation of Working Memory

– However, later studies showed that memory span for words like “Cricket” and “Bishop” was greater than for words like “Harpoon” and “Friday”

• Harpoon and Friday have long vowel sounds and take longer to say

–Suggests that span is limited by time (about 2 seconds) rather than number of chunks

»This supports the model

Evaluation of Working Memory

• Articulatory Suppression Tasks– Demonstration

The man's laughter irritated the anxious woman

The anxious woman was cycling by the man's laughter

The trees flew up into the birds

Evaluation of Working Memory

• Baddeley and Lewis (1981)– Found that sentences with syntactic anomalies

were detected less often than sentences with semantic anomalies

• This seems to indicate that the articulatory loop is important in holding information regarding the order of words

Evaluation of Working Memory

• Weaknesses of Working Memory Model– Baddeley claims that the central executive has a

limited capacity, however, it is very difficult to measure this capacity

– Baddeley also claims that the CE can be divided into subsystems; however they have not yet been identified