IN THE NAME OF ALLAH,THE MOST MERCIFUL AND BENEFICIENT TO MANKIND

CHAPTER NO 4 WORKING MEMORY

WAQAS SULTANI

QUESTIONS

What is Working Memory?

What are Shortcoming in Baddely Model?

What is Embedded Process Model?

WORKING MEMORY

Modal Model was unable to explain serial position effect in free recall.

Working Memory has been used to reflect the idea that information often has to be retained briefly in a highly accessible state while performing cognitive task.

BADDELY WORKING MEMORY Working Memory is seen as a combination of a central

executive- a controlling attentional mechanism, and a number of subsidiary slave system.

Baddeley’s Working Memory

CENTRAL EXECUTIVE

Visuo-spatialSketch Pad

PhonologicalStore

Episodic Buffer

Visual Semantic Episodic LTM Language

VisualScibe

ArticulatoryControlProcess

PhonologicalLoop

THE PHONOLOGICAL LOOP

The Phonological loop consist of 1.Phonological store retain information for short period of time,20 sec.2.Articulatory Control process Responsible for two different function. i) Translates visual information into a speech base code

and deposit it in a phonological store. ii) It refreshes a trace in the phonological store, offsetting

the decay process.

THE PHONOLOGICAL LOOP

Phonological similarity Articulatory Suppression The Irrelevant Speech effect The Word length Effect

THE PHONOLOGICAL LOOP

Phonological Similarity

Memory is worse for items that sound alike than item differ e.g. PGTCD,RHXKW.

Occurs both visual and auditory presentation Suppress speech base code conversion for visual

information ,i.e. Suppress Articulatory control process translation.

Articulatory Suppression Repeatedly say a word, such as the, over and over out load. This activity occupies the A.C.P. Still phonological effect for auditor item

THE PHONOLOGICAL LOOP

The Irrelevant Speech Effect Two groups of subject recall visually presented

consonants, but one group saw consonants with some irrelevant speech in background.

Second group was unable to recall. Phonemes from irrelevant speech enter the

phonological store and have interference. i) Articulatory suppression should remove

Irrelevant Speech effect. Single Phonemes or multiple phonemes should

have same effect. Tones should have no effect

THE PHONOLOGICAL LOOP

The word length effect Short words (dog) are recalled better than long words

(gentleman) In all cases, words of one syllable were recalled better

than words for four syllables Syllable based word length effect Words with fewer syllable (stoat) are recalled better than

words with more syllable (Australia) The shorter the items, the more can be rehearsed before a

particular trace decays (W.M) Time based word length effect Even when items are equated for meaning and word

frequency if one set of words takes less time to pronounce than another set ,memory will be better for shorter items.

S=r x t

Syllable Based Word Length Effect

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Time Based Word Length Effect

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EPISODIC BUFFER

How items are recalled at all when subjects engage in Articulatory suppression,

Baddely added another system to working memory, the episodic buffer, backup store, capable of supporting serial recall.

CRITIQUE OF WORKING MEMORY

1.Time based word length effect can be observed only with original set of stimuli. Captan conducted an experiment in which he showed only 65.45% of short words are recalled compared to 76.4% of long word.

2. Working memory has continual inability to explain precisely items in the phonological store interference (phonological similarity).

3. Why pure tone disrupt serial recall.4. Magnitude of the irrelevant speed effect is related to

phonological similarity b/w relevant and irrelevant items5. It does not explain the basic modality effect, the better

recall of final item in list that is presented auditory rather than visually

6. How, many systems interacts7. Order in which information is retained.

Embedded Processes Model

In Cowan’s embedded processes model, the term working memory “refer to cognitive processes that retain information in an unusually accessible state.

It differs from Baddely working memory in following respects

i) It does not divide immediate memory into separate subsystems.

ii) It specifically include a long term memory contributionTwo approaches are used to explain it I) Simulation approach to explain. ii) Simple approach

The Embedded Processes Model

Central Executive(directs and control voluntary processing)

Activated Memory

Focus ofAttention

Long Term Memory

SensoryStore

Stimulus

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A subset of information in memory is in a temporarily heightened state of activation.

A subset of this information in memory is in focus of attention.

An item can be activated but not the focus of attention, all items that are in focus of attention, however are activated.

This model also focus on nonverbal sounds and tactile information.

An item can retain in focus of attention through rehearsal but also through other processes like searching.

Working memory is essentially activated long term memory. Problems: 1. Activation is very often not defined very precisely. 2. The second problem concerns the assumption of

deactivation