Phonological Loop model (Working Memory) - created from Mind Map

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developmental & cross-linguistic differences

developmental differences

cross-linguistic differences

younger children have poorer recall performance on longer spoken words compared to same stimuli presented as images

faster rehearsal means better recall (more rehearsal per per 2sc)

developmental growth of memory span, Dempsey (1981)

as children's rate of speech increases so does their recall span, Nicholas (1981)

differences with mean digit span correlates with differences in how long it takes to say them

NOTE: these are correlations not causal relations

older children (7yo) show word-length effect in both modalities, Hitch et al. (1988)

Irrelevant speech effect

Salamé and Baddeley (1982) ignoring irrelevant speech was more interfering than other irrelevant noise

Macken & Jones (1995) contradictory evidence that unattended non-speech (tones) can cause the same disruptive effect

possible both theories correct in different situations

demonstrates unattended speech enters phonological store (Blocking subvocalised word stimuli) BUT other noises don't

Suppression eliminates the irrelevant speech effect (possibly by blocking word encoding)

possibly due to broader memory mechanisms rather than phonological loop

neurological study

Vallar & Baddeley (1984) - studied P.V. who showed selective verbal memory deficit

Paulesu et al. (1993)- used PET scans for 3 tasks

Left parietal lesion from stroke- only left with 2 digit auditory span yet fluent and normal rate of speech

this is an example of dissociation suggesting storage and rehearsal are separate

Poor recall with phonemically similar words- possible phonological store damage? Had no word length effect- also support phonological store damage theory

better memory span with visual words than spoken

subvocal rehearsal wouldn't help recall shorter words rather than long words

showed no phonemic similarity or word length effect

possibly compensating for phonological loop damage by using her visio-spatial scratchpad more

task assumptions- phonological loop associated with Broca's area and supramarginal gyrus. rehearsal associated with Broca's area. phonological store associated with supramarginal gyrus. if these assumptions are correct!

theoretical issues

it doesn't explain irrelevant speech effect

Lovatt et al. (2000)- challenged word length effect. claimed word complexity was responsible. word length effect could be eliminated if complexity was the same.

Hulme et al. (1984)- challenged rehearsal is affected by word length. example: 4yo not developed rehearsal ability showed word length effect.

Cowan et al. (1992)- demonstrated word length effect caused by output delays (doesn't affect rehearsal)

Baddeley (2000) - suggested a 4th component- the episodic buffer.

addressing the issues:

explains that articulatory suppression which 'should' eliminate recall by occupying all resources (rehearsal/subvocalisation), thereby preventing visual stimuli registering in the phonological loop, has only a weak effect.

evidence shows visual similarity of word stimuli affect span. suggesting visual and phonological info are bound. therefore, a separate system involved.

very amnesic patients (damaged episodic LTM) can keep current info in mind (not learned). eg. Tulving recorded a patient could remember the objective in a game of bridge, the cards played and the score across a series of games. suggesting if STM & LTM not linked there must be another store.

create a new model from scratch

revise the model addressing its deficiencies

use computational modelling to create alternative models.

phonological store

stores small amount of what's seen/heard

subvocalisation process

speech automatic access to loop. visual stimuli needs recoding

Phonological working memory, Baddeley (1975)

articulatory suppression, Baddeley (1984)

phonemic similarity effect

secondary task involving repetition of irrelevant words

memory span reduced

word length effect reduced in both modalities

phonemic similarity effect reduced in visual stimuli

eliminates word-length effect for both modality

only eliminates phonemic similarity effect in visual stimuli

word-length effect

more difficult to remember similar sounding words

Phonological Loop model (Working Memory)