Speech production deficits in early readers: predictors of risk

Speech problems and reading disorders are linked, suggesting that speech problems may potentially be an early marker of later difficulty in associating graphemes with phonemes. Current norms suggest that complete mastery of the production of the consonant phonemes in English occurs in most children at around 6–7 years. Many children enter formal schooling (kindergarten) around 5 years of age with near-adult levels of speech production. Given that previous research has shown that speech production abilities and phonological awareness skills are linked in preschool children, we set out to examine whether this pattern also holds for children just beginning to learn to read, as suggested by the critical age hypothesis. In the present study, using a diverse sample, we explored whether expressive phonological skills in 92 5-year-old children at the beginning and end of kindergarten were associated with early reading skills. Speech errors were coded according to whether they were developmentally appropriate, position within the syllable, manner of production of the target sounds, and whether the error involved a substitution, omission, or addition of a speech sound. At the beginning of the school year, children with significant early reading deficits on a predictively normed test (DIBELS) made more speech errors than children who were at grade level. Most of these errors were typical of kindergarten children (e.g., substitutions involving fricatives), but reading-delayed children made more of these errors than children who entered kindergarten with grade level skills. The reading-delayed children also made more atypical errors, consistent with our previous findings about preschoolers. Children who made no speech errors at the beginning of kindergarten had superior early reading abilities, and improvements in speech errors over the course of the year were significantly correlated with year-end reading skills. The role of expressive vocabulary and working memory were also explored, and appear to account for some of these findings

The Role of Vocal Practice in Constructing Phonological Working Memory

Purpose: In this study, the authors looked for effects of vocal practice on phonological working memory. Method: A longitudinal design was used, combining both naturalistic observations and a nonword repetition test. Fifteen 26-month-olds (12 of whom were followed from age 11 months) were administered a nonword test including real words, "standard" nonwords (identical for all children), and nonwords based on individual children's production inventory (IN and OUT words). Results: A strong relationship was found between (a) length of experience with consonant production and (b) nonword repetition and between (a) differential experience with specific consonants through production and (b) performance on the IN versus OUT words. Conclusions: Performance depended on familiarity with words or their subunits and was strongest for real words, weaker for IN words, and weakest for OUT words. The results demonstrate the important role of speech production in the construction of phonological working memory

Quantifying Sources of Variability in Infancy Research Using the Infant-Directed-Speech Preference

Psychological scientists have become increasingly concerned with issues related to methodology and replicability, and infancy researchers in particular face specific challenges related to replicability: For example, high-powered studies are difficult to conduct, testing conditions vary across labs, and different labs have access to different infant populations. Addressing these concerns, we report on a large-scale, multisite study aimed at (a) assessing the overall replicability of a single theoretically important phenomenon and (b) examining methodological, cultural, and developmental moderators. We focus on infants’ preference for infant-directed speech (IDS) over adult-directed speech (ADS). Stimuli of mothers speaking to their infants and to an adult in North American English were created using seminaturalistic laboratory-based audio recordings. Infants’ relative preference for IDS and ADS was assessed across 67 laboratories in North America, Europe, Australia, and Asia using the three common methods for measuring infants’ discrimination (head-turn preference, central fixation, and eye tracking). The overall meta-analytic effect size (Cohen’s d) was 0.35, 95% confidence interval = [0.29, 0.42], which was reliably above zero but smaller than the meta-analytic mean computed from previous literature (0.67). The IDS preference was significantly stronger in older children, in those children for whom the stimuli matched their native language and dialect, and in data from labs using the head-turn preference procedure. Together, these findings replicate the IDS preference but suggest that its magnitude is modulated by development, native-language experience, and testing procedure

Late talking toddlers : relating early phonological development to later language advance

Background. Expressive Late talkers are identified as children with an unusually small productive vocabulary for their age, in the absence of any other known neurological, sensory or cognitive deficit. Their lexical delay has been found to be associated with phonetic delay. Aims. The two primary goals of this study are (1) to provide intensive analyses of phonetic and phonological characteristics of late talkers (LTs) at the end of the single word period as a basis for comparing their speech with that of typically developing children (TDs), not at the same age but at the same developmental point; (2) to compare the relative phonological, lexical, morphological and syntactic advance of the same two groups 14 months later, based on analysis of spontaneous language use, and to relate this advance to phonetic and phonological resources at the earlier measurement point. Methods and procedures. Time 1 analyses included assessment of volubility, size of consonant inventory, percent consonants correct and extent of consonant variegation and of the use of selected prosodic patterns or ‘templates’. Time 2 analyses assessed advance in phonology (percent consonants correct), lexicon (diversity of verb and function word types), morphology (provision of obligatory morphemes) and syntax (MLU, IPSyn). Outcomes and results. Although three groups differing in age at achieving Time 1 lexical criterion were identified (TDs, LTs and ‘transitional’ LTs or TLTs), there is little evidence of group differences in other measures of linguistic advance at either sampling point, when the groups are compared at the same lexical level. Exploratory statistical analyses using Canonical Correlations revealed that a combination of high age at Time 1, small consonant inventory and low phonetic variegation are strong predictors of low accuracy in consonant use and relatively poor lexicon, morphology and syntax at Time 2, while dependence on a limited set of phonological patterns at Time 1 was significantly correlated more specifically with slower morphological advance at Time 2. Conclusions and implications. The study found that, once the groups are equated for lexical level, the linguistic skills of LTs as a group are not distinguishable from those of TDs in either the early period of phonological development or the year following the end of the single-word period. Nevertheless, based on the relation of Time 1 to Time 2 measures within individuals, the study also demonstrates that phonetic and phonological knowledge and skills constitute a key foundation for later linguistic advance, as regards grammar as well as phonology