Phonological Short-term Memory and its Relationship to Language in Williams Syndrome

Abstract

Williams syndrome (WS), a rare neurodevelopmental disorder of genetic origin, is characterised by a relative advantage of language over more serious deficits in other cognitive domains. In this study the relationship of phonological short-term memory to WS language, in particular vocabulary, was explored. Using Gathercole and Baddeley's Children's Test of Nonword Repetition (CNRep) (Gathercole & Baddeley, 1996), we examined the pattern of performance by WS participants on that task and compared it to performance on measures of receptive language, visuospatial ability, and digit span. In addition, a comparison was made of WS nonword repetition score with those of two groups of individually matched normally developing 5-year-olds, one on the basis of nonverbal test age and the other on the basis of verbal test age. As expected WS repetition scores showed an effect of nonword length but not of phonological complexity. Nonwords that were relatively wordlike were better repeated than nonwords that were less wordlike. CNRep scores were correlated with test ages on TROG, Ravens, and digit span but not with chronological age. Test age on the CNRep was at a similar level to that on TROG, Ravens, and digit span but significantly lower than on BPVS. The results lend support to the view that phonology in WS is a relative strength. In contrast, despite relatively good productive and receptive vocabulary, certain aspects of the processes of word learning in WS do not seem to develop beyond that of normal 4year-olds. The good vocabulary scores of older children and adults with WS may be simply due to their relatively good phonological short-term memory.

Language differences in verbal short-term memory do not exclusively originate in the process of subvocal rehearsal

“…One possibility, considered earlier, is that language differences in recall reflect the use of long-term knowledge to support recall performance. Within a particular language it is consistently found that familiar words are recalled better than are unfamiliar nonwords (Hulme et al, 1991) and that highly wordlike nonwords are more accurately recalled than non-wordlike nonwords (Gathercole, 1995;Gathercole et al, 1999;Gathercole et al, 1991;Grant et al, 1997;van Bon & van der Pijl, 1997). It has been suggested that these phenomena arise from the use of long-term representations of phonological information, both of the phonological structure of specific lexical items and of the phonotactic properties of a language , to support the recall of degraded memory traces held in the phonologicalstore.…”

“…The superior recall of words over nonwords has led to the suggestion that immediate memory performance is in some way enhanced by prior phonologically based lexical knowledge; nonwords are unable to benefit from such support because no long-term representation exists for unfamiliar word forms (Hulme et al, 1991). A second type of long-term knowledge support relates to knowledge concerning the phonotactic properties of a language; for unfamiliar words (or nonwords whose phonological structure conforms to the phonotactics of the language), those items that contain high-probability phoneme combinations are better recalled than those containing low-probability phoneme combinations (Gathercole, Frankish, Pickering, & Peaker, 1999; see also Gathercole, 1995;Gathercole, Willis, Emslie, & Baddeley, 1991;Grant et al, 1997;van Bon & van der Pijl, 1997).…”

Using developmental trajectories to examine verbal and visuospatial short-term memory development in children and adolescents with Williams and Down syndromes

“…Phillips, Jarrold, Baddeley, Grant, & Karmiloff-Smith, 2004), comparisons of the verbal and performance IQ scores of individuals with WS have generally shown a verbal superiority (e.g. Grant et al, 1997;Levy & Bechar, 2003). Individuals with DS usually display "flatter" profiles (Jarrold, Baddeley, & Phillips, 2007), but have often exhibited expressive language difficulties (e.g.…”

Articulating Novel Words: Children's Oromotor Skills Predict Nonword Repetition Abilities

“…NWR tasks have been used with many clinical populations (Gathercole, 2006;Bishop et al, 2006;Conti-Ramsden et al, 2001;Grant et al, 1997;Laws & Gunn, 2004;Graf-Estes et al, 2007) and across languages (Sahlen et al, 1999;reviewed in Coady & Evans, 2008). However, there is no current consensus about which underlying skills, including sensorimotor skills, contribute to NWR performance, and in what proportion (Coady & Evans, 2008;Snowling et al, 1981Snowling et al, , 1986.…”