Table 1.
Studies using non-word repetition tasks (NRTs) in children developing language typically
| Study | Purpose | Participants | Primary results |
|---|---|---|---|
| Gathercole and Baddeley (1989) | Correlate phonological memory (non-word repetition and digit span) with receptive vocabulary | 104 children with NL, tested as they were entering school (age 4—5) and again a year later | (1) Accuracy increased with age. (2) Accuracy decreased as non-word length and complexity increased. (3) Accuracy at age 4 predicted vocabulary at age 5 |
| Gathercole et al. (1991a) | Correlate phonological working memory and sensitivity with receptive vocabulary | 57 children with NL, age 4, and 51 children with NL, age 5 | Phonological memory predicted vocabulary, but phonological sensitivity did not |
| Gathercole et al. (1991b) | Correlate phonological memory and sensitivity with receptive vocabulary, and consider lexical influences on repetition accuracy | 103 children with NL, tested as they entered school (age 4—5), then one year later, and again 2 years later | (1) No accuracy differences due to complexity. (2) Higher accuracy for more word-like non-words |
| Gathercole et al. (1992) | Longitudinal study examining the reciprocal influences of vocabulary and repetition accuracy by comparing cross-lagged partial correlations | 80 children with NL, tested over a 4-year period (ages 4, 5, 6, and 8) | Repetition accuracy at age 4 predicted receptive vocabulary at age 5, but vocabulary at ages 5 and 6 predicted repetition at ages 6 and 8, respectively |
| Gathercole and Adams (1993) | Use NRT to measure phonological memory in very young children, for whom memory measures are typically unreliable | 54 children with NL, aged 2;10 to 3;1 | Repetition accuracy correlated significantly with receptive vocabulary, but digit span did not |
| Dollaghan et al. (1993) | Examine lexical effects on repetition accuracy by having children repeat non-words varying in the lexical status of stressed syllables | 11 boys with NL, aged 9;10 to 12;0 | Non-words containing real words were repeated more accurately than those non-lexical stressed syllables |
| Michas and Henry (1994) | Examine the relationship between phonological memory and vocabulary, and how phonological; memory affects the acquisition of new words | 48 children with NL, aged 5;2 to 6;2 | Non-word repetition ability predicted the ability to learn new words, providing direct evidence for the phonological memory-word learning link |
| Gathercole and Adams (1994) | Examine the relationship between phonological working memory and vocabulary, and betweern phonological working memory and other cognitive skills | 70 children with NL, tested first at age 4;1 (3;11–4;4), and again at age 5;3 (4;10–5;7) | Non-word repetition accounted for variance in receptive vocabulary, but not in children’s knowledge of number |
| Gathercole (1995) | Compare phonological working memory and lexical knowledge influences on non-word repetition accuracy | 70 children with NL, tested first at age 4;1, and again at age 5;3 | Long-term lexical knowledge supports repetition of more word-like non-words, while phonological memory supports repetition of less word-like non-words |
| Adams and Gathercole (1995) | Examine the relationship between phonological memory and spoken language development | 38 children with NL, aged 2;10 to 3;1, separated into high- and low-phonological memory groups | Children in the high-phonological memory group (better non-word repetition ability) produced longer, more grammatically complex sentences |
| Dollaghan et al. (1995) | Replicate their 1993 study with a larger group of children | 30 boys with NL, aged 9;10 to 12;5 | Lexical knowledge influences non-word repetition accuracy, replicating their previous study |
| Adams and Gathercole (1996) | Replicate their 1995 study using a more constrained narrative (The Bus Story; Renfrew 1966) | 89 children with NL, aged 4;10 to 5;8 | Non-word repetition ability predicted narrative recall and grammatical complexity |
| Bowey (1996) | Examine the role of phonological memory and phonological sensitivity in receptive vocabulary | 205 children with NL, mean age 5;5 | Phonological memory and sensitivity measures accounted for variance in vocabulary. Factor analyses extracted a single factor — a latent phonological processing factor |
| Gathercole et al. (1997) | Examine the role of phonological memory in a word-learning task | 65 children with NL, aged 5;1 to 6;3 | Learning new words was predicted by repetition accuracy, but learning to associate two familiar words was not |
| Gathercole et al. (1999) | (1) Examine if the link between vocabulary and non-word repetition arises from articulation or from encoding and memory. (2) Examine the relationship between phonological memory and vocabulary in older adolescents | (1) 18 children with NL, aged 4;0 to 4;3. (2) 65 children with NL, aged 5;1 to 6;3 and 60 adolescents with NL, aged 13;4 to 14;5 | (1) Non-word repetition taps phonological encod ing and/or memory skills rather than output variables. (2) The link between phonological memory and vocabulary continues into adolescence |
| Metsala (1999) | Examine changes in non-word repetition accuracy resulting from developmental changes in phonological representations | In Experiment 1, 32 children with NL, aged 3;11–4;11, and 29 children with NL, aged 5;0 to 6;4. In Ex. 3, a third group of 36 children with NL, aged 3;0 to 4;8 | Memory and phonological awareness correlated with repetition accuracy, but only phonological awareness correlated with vocabulary. Repetition did not account for variance in vocabulary over that accounted for by phonological awareness |
| Adams and Gathercole (2000) | Examine the role of phonological working memory on grammatical complexity | Two groups of 15 children with NL, aged 4;6 to 5;0, matched on non-verbal IQ, but differing in non-word repetition ability | Children in the high-repetition group produced longer, more grammatically complex sentences using a wider variety of lexical items |
| Beckman and Edwards (2000) | Examine lexical effects on non-word repetition accuracy by comparing non-words containing attested sequences to those containing unattested sequences | 16 children with NL, aged 3;2 to 5;0. Replicated with 24 children with NL, aged 3;2 to 5;4 | Children more accurately produced attested CV and CC sequences, relative to unattested sequences. There was no difference between attested and unattested VC sequences |
| Simkin and Conti-Ramsden (2001) | Provide norms for the CNRep and two morphological-marking tasks | 100 children with NL in their final year of primary school, aged 10;5–11;6 | Children’s median score was 38 of 40 non-words repeated accurately, indicating that 10.5-year-old children are at ceiling in non-word repetition accuracy |
| Munson (2001) | Compare accuracy and fluency of non-words differing in phonological pattern frequency | Nine children with NL, aged 3;5 to 4;6, and nine older children with NL, aged 7;4 to 8;11 | Attested sequences in non-words were repeated more accurately and with shorter durations than unattested sequences |
| Bowey (2001) | Longitudinal study examining the link between non-word repetition and subsequent vocabulary | 71 children with NL tested longitudinally, first at age 5;11 and again at 9;7 | Repetition accuracy and vocabulary predicted each other at subsequent time frames. Replicates previous finding of a latent phonological processing ability that supports phonological memory and sensitivity |
| Edwards et al. (2004) | Examine how vocabulary size and phonotactic frequency affect repetition accuracy | 22 adults and 104 children with NL, divided into three age groups: (1) 43 children, mean age 4;2; (2) 38 children, mean age 5;6; and (3) 23 children, mean age 8;1 | All children repeated non-words with higher frequency phonological patterns more accurately than those with lower frequency, but this effect decreased with age, possibly mediated by increasing vocabulary size |
| Zamuner et al. (2004) | Examine whether phonotactic frequency influences repetition accuracy in a group of very young children | 29 children with NL, aged 1;8 to 2;4, mean age 2;0 | Children repeated coda consonants in CVC non-words more accurately when they occurred in high phonotactic frequency non-words rela tive to the same consonants in low phonotactic frequency non-words |
| Coady and Aslin (2004) | Examine lexical influences on repetition accuracy by manipulating frequency of smaller and larger phonological units | Three groups of 24 children with NL. Each group contained a younger cohort, aged 2;4 to 2;8, and an older cohort, aged 3;4 to 3;8 | By the age of 2;6, children are sensitive to the frequency of individual segments, and sensitivity to all aspects of sound structure increase over development |