Reduced speaking rate as an early predictor of reading disability

Exploring the Overlap Between Dyslexia and Speech Sound Production Deficits

Purpose

Children with dyslexia have speech production deficits in a variety of spoken language contexts. In this article, we discuss the nature of speech production errors in children with dyslexia, including those who have a history of speech sound disorder and those who do not, to familiarize speech-language pathologists with speech production-specific risk factors that may help predict or identify dyslexia in young children.

Method

In this tutorial, we discuss the role of a phonological deficit in children with dyslexia and how this may manifest as speech production errors, sometimes in conjunction with a speech sound disorder but sometimes not. We also briefly review other factors outside the realm of phonology that may alert the speech-language pathologist to possible dyslexia.

Results

Speech-language pathologists possess unique knowledge that directly contributes to the identification and remediation of children with dyslexia. We present several clinical recommendations related to speech production deficits in children with dyslexia. We also review what is known about how and when children with speech sound disorder are most at risk for dyslexia.

Conclusion

Speech-language pathologists have a unique opportunity to assist in the identification of young children who are at risk for dyslexia.

Basic Measures of Prosody in Spontaneous Speech of Children With Early and Late Cochlear Implantation

PURPOSE

Relative to normally hearing (NH) peers, the speech of children with cochlear implants (CIs) has been found to have deviations such as a high fundamental frequency, elevated jitter and shimmer, and inadequate intonation. However, two important dimensions of prosody (temporal and spectral) have not been systematically investigated. Given that, in general, the resolution in CI hearing is best for the temporal dimension and worst for the spectral dimension, we expected this hierarchy to be reflected in the amount of CI speech's deviation from NH speech. Deviations, however, were expected to diminish with increasing device experience.

METHOD

Of 9 Dutch early- and late-implanted (division at 2 years of age) children and 12 hearing age-matched NH controls, spontaneous speech was recorded at 18, 24, and 30 months after implantation (CI) or birth (NH). Six spectral and temporal outcome measures were compared between groups, sessions, and genders.

RESULTS

On most measures, interactions of Group and/or Gender with Session were significant. For CI recipients as compared with controls, performance on temporal measures was not in general more deviant than spectral measures, although differences were found for individual measures. The late-implanted group had a tendency to be closer to the NH group than the early-implanted group. Groups converged over time.

CONCLUSIONS

Results did not support the phonetic dimension hierarchy hypothesis, suggesting that the appropriateness of the production of basic prosodic measures does not depend on auditory resolution. Rather, it seems to depend on the amount of control necessary for speech production.

A longitudinal study of infants' early speech production and later letter identification

Letter identification is an early metric of reading ability that can be reliability tested before a child can decode words. We test the hypothesis that early speech production will be associated with children's later letter identification. We examined longitudinal growth in early speech production in 9 typically developing children across eight occasions, every 3 months from 9 months to 30 months. At each occasion, participants and their caregivers engaged in a speech sample in a research lab. This speech sample was transcribed for a variety of vocalizations, which were then transformed to calculate consonant-vowel ratio. Consonant-vowel ratio is a measure of phonetic complexity in speech production. At the age of 72 months, children's letter knowledge was measured. A multilevel model including fixed quadratic age change and a random intercept was estimated using letter identification as a predictor of the growth in early speech production from 9-30 months, measured by the outcome of consonant-vowel ratio. Results revealed that the relation between early speech production and letter identification differed over time. For each additional letter that a child identified, their consonant-vowel ratio at the age of 9 months increased. As such, these results confirmed our hypothesis: more robust early speech production is associated with more accurate letter identification.

Paired associate learning deficits in poor readers: The contribution of phonological input and output processes

It is well-established that poor readers exhibit deficits in paired associate learning (PAL), and there is increasing evidence for a phonological locus of these deficits. However, it remains unclear whether poor performance stems from difficulties specific to the phonological output system or difficulties that affect both phonological input and output processes. Understanding these deficits is important not only in the context of PAL but also for informing broader theories of typical and atypical reading development. We developed a novel paradigm that allowed us to assess PAL in the presence and absence of phonological output demands. In total, 14 poor readers and 14 age-matched controls were first trained to criterion in verbal-visual PAL before being tested in the visual-verbal direction. The results showed that poor readers learned at the same rate as controls in verbal-visual PAL, even when the nonword stimuli were phonologically confusable. Yet, despite having reached the same criterion as controls in verbal-visual PAL, poor readers exhibited robust impairments for those same paired associates in visual-verbal PAL. The overall pattern of results is most consistent with the conclusion that PAL deficits reflect impairments to the phonological output system; however, results that may challenge this interpretation are also discussed.

Increased Response to Altered Auditory Feedback in Dyslexia: A Weaker Sensorimotor Magnet Implied in the Phonological Deficit

PURPOSE

The purpose of this study was to examine whether developmental dyslexia (DD) is characterized by deficiencies in speech sensory and motor feedforward and feedback mechanisms, which are involved in the modulation of phonological representations.

METHOD

A total of 42 adult native speakers of Dutch (22 adults with DD; 20 participants who were typically reading controls) were asked to produce /bep/ while the first formant (F1) of the /e/ was not altered (baseline), increased (ramp), held at maximal perturbation (hold), and not altered again (after-effect). The F1 of the produced utterance was measured for each trial and used for statistical analyses. The measured F1s produced during each phase were entered in a linear mixed-effects model.

RESULTS

Participants with DD adapted more strongly during the ramp phase and returned to baseline to a lesser extent when feedback was back to normal (after-effect phase) when compared with the typically reading group. In this study, a faster deviation from baseline during the ramp phase, a stronger adaptation response during the hold phase, and a slower return to baseline during the after-effect phase were associated with poorer reading and phonological abilities.

CONCLUSION

The data of the current study are consistent with the notion that the phonological deficit in DD is associated with a weaker sensorimotor magnet for phonological representations.

Tackling the 'dyslexia paradox': reading brain and behavior for early markers of developmental dyslexia

Developmental dyslexia is an unexplained inability to acquire accurate or fluent reading that affects approximately 5-17% of children. Dyslexia is associated with structural and functional alterations in various brain regions that support reading. Neuroimaging studies in infants and pre-reading children suggest that these alterations predate reading instruction and reading failure, supporting the hypothesis that variant function in dyslexia susceptibility genes lead to atypical neural migration and/or axonal growth during early, most likely in utero, brain development. Yet, dyslexia is typically not diagnosed until a child has failed to learn to read as expected (usually in second grade or later). There is emerging evidence that neuroimaging measures, when combined with key behavioral measures, can enhance the accuracy of identification of dyslexia risk in pre-reading children but its sensitivity, specificity, and cost-efficiency is still unclear. Early identification of dyslexia risk carries important implications for dyslexia remediation and the amelioration of the psychosocial consequences commonly associated with reading failure.

The speed of articulatory movements involved in speech production in children with dyslexia

A group of children with dyslexia (mean ages 9 and 14 years) was studied, together with group of children without dyslexia matched for age. Participants were monolingual native speakers of the Bosnian language with transparent orthography. In total, the diagnostic tests were performed with 41 children with dyslexia and 41 nondyslexic children. The participants were asked to produce monosyllables, /pa/, /ta/, and /ka/, and the trisyllable /pataka/, as fast as possible. Analysis was undertaken in four ways: (1) time of occlusion duration for plosives (duration of stop), (2) voice onset time for plosives, (3) diadochokinetic rate--articulators rate measured by pronunciation of monosyllables and the trisyllable, and (4) time of moving articulators from one gesture to another-time of interval length (from the explosion of one plosive to the start of the explosion of another plosive). The results suggest that children with dyslexia have significant problems with the speed of articulatory movements involved in speech production.

Language development, literacy skills, and predictive connections to reading in Finnish children with and without familial risk for dyslexia

Discriminative language markers and predictive links between early language and literacy skills were investigated retrospectively in the Jyväskylä Longitudinal Study of Dyslexia in which children at familial risk for dyslexia have been followed from birth. Three groups were formed on the basis of 198 children's reading and spelling status. One group of children with reading disability (RD; n = 46) and two groups of typical readers from nondyslexic control (TRC; n = 84) and dyslexic families (TRD; n = 68) were examined from age 1.5 years to school age. The RD group was outperformed by typical readers on numerous language and literacy measures (expressive and receptive language, morphology, phonological sensitivity, RAN, and letter knowledge) from 2 years of age onward. The strongest predictive links emerged from receptive and expressive language to reading via measures of letter naming, rapid naming, morphology, and phonological awareness.

An exploratory study of the development of early syllable structure in reading-impaired children

Babbling between the ages of 8 and 19 months was examined in 19 children, 13 of whom were at high risk for reading disorder (RD) and 6 normally reading children at low familial risk for RD. Development of syllable complexity was examined at five periods across this 11-month window. Results indicated that children who later evidenced RD produced a lower proportion of canonical utterances and less complex syllable structures than children without RD. As syllable complexity is an early indicator of phonological sophistication, differences at this level may offer a window into how the phonological system of children with RD is structured. Future directions for this line of research are discussed.

Phonological awareness and types of sound errors in preschoolers with speech sound disorders

PURPOSE

Some children with speech sound disorders (SSD) have difficulty with literacy-related skills, particularly phonological awareness (PA). This study investigates the PA skills of preschoolers with SSD by using a regression model to evaluate the degree to which PA can be concurrently predicted by types of speech sound errors.

METHOD

Preschoolers with SSD (n = 43) participated in PA and speech sound production assessment. Errors from a 125-item picture naming task were coded in 2 ways: (a) considering all consonant errors equally (percentage of consonants correct [PCC]) and (b) using a 3-category system that captures component features of sound errors (typical sound changes, atypical sound changes, and distortions). PA tasks included rhyme matching, onset matching, onset segmentation and matching, and blending.

RESULTS

Variance in a PA composite score could be predicted partly by vocabulary and age (33%). Atypical sound changes accounted for an additional 6% of variance in PA, but distortions and typical errors did not account for significant variance. When the same consonant errors were analyzed using PCC, speech errors did not predict significant variance in PA.

CONCLUSIONS

Poorer PA is associated with lower receptive vocabularies and more atypical sound errors. Results are interpreted in the context of the accuracy of phonological representations.

Hesitation patterns in third grade children's derived word productions

Hesitations have been considered to serve both cognitive and linguistic functions. This study presents analyses of children's hesitations while producing English derived words with the suffix -ity. Two questions were considered: Do children's linguistic skills influence their use and frequency of hesitations when producing derived words, and do children's use of hesitations vary as a function of word frequency. Eight real words derived with the suffix -ity were produced by 20 third grade children and analysed for different hesitation types. Four of the target words were high in lexical frequency, and four were low in lexical frequency. Results indicated varying hesitation patterns based upon stress accuracy skill. Children with good stress accuracy skills tended to produce false starts, whereas children with poor stress accuracy skills tended to produce glottal stops and intra-word pauses. Word frequency had a specific effect only for children with good stress accuracy skills.

A longitudinal study of speech timing in young children later found to have reading disability

PURPOSE

This study examined the development of timing characteristics in early spontaneous speech of children who were later identified as having reading disability (RD).

METHOD

Child-adult play sessions were recorded longitudinally at 2 and 3 years of age in 27 children, most of whom were at high familial risk for RD. For each speaking turn, the number of syllables was determined and an acoustic analysis measured the time allocated to articulation, pausing before speaking, and pausing during speaking.

RESULTS

In grade school, a reading battery identified 9 children with RD and 18 children without RD (9 at high risk, 9 at low risk). Early speaking rate was significantly slower in the group with RD, with significantly different patterns of pausing compared with children without RD. Group differences became more distinct by age 3, as longer speaking turns were attempted.

CONCLUSIONS

The results are discussed in terms of speech and language formulation. Phonetic plans may be shorter and/or less specified in children with RD, surfacing as slow, short speaking turns with increased pausing relative to articulation. This explanation is consistent with several accounts of RD and provides a perspective on how speech and language deficits may manifest during spontaneous verbal interactions between young children and adults.

Stalls and revisions: a developmental perspective on sentence production

PURPOSE

The purpose of this research was to test the empirical validity of the stall-revision distinction and to provide a characterization of the development of sentence production using this distinction.

METHOD

The stall-revision dichotomy for sentence disruptions was studied in 20 typically developing children. The children's production of short sentences was observed from 21 to 33 months of age. Developmental changes in stall and revision rates were analyzed using hierarchical linear modeling, time centered at 27 months. Differences between stall and revision rates across 2 levels of sentence length were also explored with repeated-measures analysis of variance when the children were 33 months of age.

RESULTS

A clear development trend was observed for revision rate. At 27 months of age, revisions occurred in approximately 1% of children's sentences and increased with age. No significant individual differences were apparent in the growth parameters for revision rate. In contrast, group developmental trends in stall rate were not discernable. However, stall rate increased significantly with sentence length, whereas revision rate remained constant.

CONCLUSION

The contrasting pattern of findings provides support for the stall-revision dichotomy. The authors argue that the developmental changes in revision rate reflect changes in the children's ability to monitor their language production.