Presented by: Odelya Ohana

Gathercole & Baddeley, 1989NWR phonological short-term memory.

Gathercole, 2006Phonological storage is the key capacity common to NWR and vocabulary acquisition.

Gathercole NWR and vocabulary acquisition are constrained

by “thequality of temporary storage of phonologicalrepresentations...”

Chiat-Developmental trajectory.

Early Phonological SensitivityChildren at a very young age (less than a

year) deploy skills in recognizing and storing details of phonological input.

badad

aya

diurgafff

rrrdobumomba

urfff

bu

do

rrr

1 year olds-

Rhythmic patterns

segmenting words for Segmental combinations

storage

Children come to NWR with previously established phonological representations and phonological processing skills.

Early phonological sensitivity hypothesis- (Chiat 2001)

variations in children’s early sensitivity to phonology

reduced sensitivity to phonological details

University of Wales infants’ responses to speech infants’

performance on input at age 6-12 months & NWR at age 2-3

years

hello! cute baby!

Chikuakua! Zinposhinz

a!

Early phonological sensitivity hypothesis-

Factors influential in early phonological development are also influential in NWR.

Infants show very early sensitivity to prosodic structures and use prosodic structures to segment the stream of speech.

Chiat & Roy, 2004

Groups:TD children at age 2-4Clinically referred children at age 2.5-4

The experiment was controlled for prosodic structure of

items and included analysis of prosodic effects.

Findings:

The overall performance of the clinically referred group was very much poorer than that of the TD group.

Errors of syllable omission were also significantly more frequent in the clinically referred group.

Both groups of children showed effects of prosodic structure on syllable omission that could override effects of length.

prosodic structure syllable omission

All children were many times more likely to omit unstressed syllable that precede the stress than those that follow the stress in two-syllable items.

Loss of pre-stress syllables in two-syllable items was nearly double than that of post-stress syllables in longer, three-syllable items.

Sahl’en, Reuterski old-Wagner, Nettelbladt, & Radeborg, 1991

Swedish 5-year-olds with language impairment.

Findings:

Children omitted six times more pre-stress syllables than

post-stress syllables.

Conclusions:

Differential sensitivity to elements of prosodic structure is very important in typically and atypically developing children, and plays a role in their NWR.

Certain weak syllables and segmental details within prosodic structures are most vulnerable.

variation in performance.

Growing Contributions of Vocabulary

Children’s growing vocabulary is an emergent source of support for NWR.

The relationship between NWR and vocabulary changes with age.

Vocabulary acquisition is influenced by several factors,

that indirectly influence NWR:

Connections between word form and meaning.

The connection between meanings and phonology.

Exposure to vocabulary.

Conclusion: the different influences on vocabulary

growth will indirectly facilitate NWR.

Insights from a Developmental Perspective

The analysis of the developmental trajectory mayaccount better for two findings that are puzzling for

thestorage-based account (mentioned at the beg.) of NWR:

1.The finding that SLI children are considerably more impaired on NWR than serial recall tasks, even when stimuli in the two tasks contain identical syllables.

Gathercole suggests that the selective deficit in NWR

may be due to fast rates of transmission of the acoustic

signal.

In NWR the stimuli is different than in other tasks

because it involves prosodic structure.

SLI children have reduced ability to register weak syllables and segmental details within a prosodic structure.

SLI children have enormous difficulty in repeating polysyllabic non-words which vary in stress, compared with strings of monosyllabic non-words whose constituent syllables are all stressed.

2. The second finding is that some children with marked impairments in NWR and serial recall at 5 years show age-appropriate vocabulary and language abilities at 8 years.

This mismatch between an early measure of phonological memory and later vocabulary is puzzling.

Gathercole suggests that a phonological storage deficit may not be sufficient to disrupt language development.

She suggests that there must be a further deficit such as “working memory”.

Children with poor NWR test at age 5 andintact vocabulary and language at age 8 vs. SLI

children

quantity- quality. non-verbal abilities.links between phonology and semantics.

Conclusions:

NWR has a developmental trajectory.

There are different forces operating at different stages in that trajectory.

A developmental perspective opens up the possibility that NWR may be “the most effective predictor of language ability” (Gatherchole, 2006).