The Babble Boot Camp turns 2: Phonetic and phonemic inventory complexity and expressive vocabulary growth in infants with Classic Galactosemia undergoing an experimental prevention therapy

Classic Galactosemia (CG) is a rare recessive metabolic disease resulting in the inability to digest galactose. Despite early detection via newborn screening and strict diet management, infants with CG are at high risk for severe speech (60%) and language (90%) disorders (Waggoner, D., Buist, N., & Donnell, 1990). Although this risk is known since birth, no preventive treatment approaches in the area of speech and language have been developed. The Babble Boot Camp (BBC) is the first experimental proactive intervention for infants with CG ages 2 to 24 months. It is designed to stimulate early vocalization, coo, babble, first words, vocabulary growth, and syntactic complexity, with the goal of preventing or at least ameliorating the expected speech and language difficulties. All children undergo close monitoring. Day-long audio recordings, collected once per month using the Language Environment Analysis (LENA) system, are the source material for pre-speech and speech measures including Mean Babbling Level (MBL), Syllable Structure Level (SSL), and phonetic and phonemic inventory complexity.
Parent questionnaires are analyzed for expressive vocabulary size. Here, findings are described for the first 9 children who underwent the BBC and an untreated control child, all with CG. The initial results are consistent with higher MBL and SSL scores in the treatment cohort, compared to the untreated control infant. In addition, most children in the treatment cohort achieved larger vocabulary sizes than the control child. Of the four oldest children in the treatment cohort, three had expressive vocabularies within normal limits at 21 months. Phonetic
inventory complexity at 11 months predicted expressive vocabulary at 18 months. Given the high risk for speech and language disorders in children with CG, these results are encouraging, but an appropriately powered clinical trial is necessary to validate these findings. The BBC is on its way to a full clinical trial with 75 families, fully funded by the National Institutes of Health.