Infant Speech Development
The early years of life play a critical role in the development of speech production. Infant vocalization emerges in early infancy (regardless of the household language) and undergoes dramatic changes during the first few years of life. We are interested on studying the role of linguistic environmental influences on infant early speech production. No doubt evidence exists that babies eventually speak their mother language; but, the age at which household language begins to influence infant babbling is debatable.
Our research aims to provide answers to the question do babies learning different languages babble differently during their first 18 months of life? The presence of cross-linguistic differences on infant babble demonstrate that the changes found in infant vocalizations before age 18 month are not fully age-related (i.e., caused by maturation of the vocal tract and oral motor control) but may be accounted for in part by the surrounding language. Acoustic studies of the development of the infant vowel space have been particularly fruitful in the search for early cross-linguistic differences in early phonetic development in our lab. Other studies have provided acoustic-phonetic descriptions of the babble produced by infants with otitis media and by infants born with very low birth weight.
These studies further illuminate the interaction between language input and maturation of speech motor control in early speech development.
In this project we are attempting to classify children with very severe primary speech delay as having difficulties that are primarily in the area of phonological planning versus those who are having difficulties that are primarily in the area of motor planning (i.e., childhood apraxia of speech). We are using the Syllable Repetition Test, the Diagnostic Evaluation of Articulation and Phonology and Maximum Performance Tasks to make this differentiation. Then, using a single subject randomization design we are comparing the relative effectiveness of an intervention that focuses on phonological planning versus auditory motor integration for children with these two types of planning difficulties. So far the results are suggesting that these types of planning difficulties can be differentiated although there is often overlap between difficulties with encoding, phonological memory and transcoding (i.e., motor planning) within children. Furthermore, individual children do respond differentially to the distinct interventions that we are using. Staring in the spring of 2015 we will be incorporating ultrasound as an intervention tool into this project. We will also be expanding the project to include older children with residual speech errors as well as children with Down Syndrome.
This project has received support from the Childhood Apraxia of Speech Association of North America and by the Ruth Ratner Miller Foundation.
The Down Syndrome Project
This project investigates speech therapy for individuals with Down syndrome and Apraxia of Speech. By comparing three different therapy protocols, our aim is to discover which is the most effective for both learning and generalization for the individual. Diversity is the norm within the population of individuals with Down syndrome, and part of this study seeks to identify whether a specific psycholinguistic profile, measured by tests, consistently aligns with a particular treatment protocol. Should this be the case, we will be one step closer to understanding the most efficient and effective treatment for these individuals.
The ECRIP Project
Children who present with a phonological disorder misarticulate more speech sounds than other children their age. They also have poorer speech perception abilities and phonological awareness abilities than their peers and are more at risk of presenting with reading difficulties. The objective of the research project was to test the relative efficacy of different combinations of three intervention components (individual therapy, home program and small group intervention) to improve speech production accuracy and phonological awareness skills in francophone children with a developmental phonological disorder. We found that the children responded very well to a combination of treatments that involved surprisingly little direct speech practice when all elements were implemented in a coherent fashion, specifically (input oriented individual speech therapy using the procedures focused stimulation, auditory bombardment, error detection tasks, and minimal pairs therapy; small group therapy targeting phonological awareness (teaching implicit knowledge of syllables, onsets and rimes); and a parent group intervention (teaching dialogic reading techniques). The intervention was implemented over a 12 week period with the individual treatment occurring first and the two group interventions following in the second 6 week block.
This randomized control trial was funded by a Social Sciences and Humanities Council of Canada grant to Dr. Susan Rvachew. The project was coordinated by Françoise Brosseau-Lapré, Ph.D., S-LP(c) who was supported by a doctoral fellowship from le Fonds de la Recherche en Santé du Québec. Dr. Brosseau-Lapré is currently an Assistant Professor at Purdue University.
The results of this study have been described in published papers, blogs, podcasts and many conference papers. Some useful links are as follows:
“A randomized trial of twelve-week interventions for the treatment of developmental phonological disorder in francophone children” (published report and complete procedure manual)
Scatterplots and Speech therapy (open access blogpost describing the trial results)
Testing Combinations of Phonological Intervention Approaches for Francophone Children (A “Behind the Science” Podcast)
The Digital Media Partnership
Click here for the link