Alternative approaches to improving language outcomes in young children

In this issue of Pediatrics, Wong et al (1) used a speech auditory brainstem response (ABR) method, administered during infancy or toddler years, to predict those infants and toddlers who would score more than one standard deviation below the mean on the language subscale of the Bayley Scales of Infant Development up to age 32 months. The speech ABR is a functional assessment of early neural responses to speech sounds, rather than to clicks or tones, obtained by EEG recordings after the repeated delivery of the auditory stimuli. As the authors point out, the significance of the finding is that early prediction could allow identification of children at high risk for language delay and provision of targeted early intervention to ideally mitigate the long-term consequences of language disorders. This commentary has two aims: (1) to point out limitations about the methods that might complicate the further development of the speech ABR technique as a universal screening tool; (2) to offer an alternative approach to improving early language skills in infants and toddlers in lieu of screening and targeted intervention.

The attractive feature about use of an ABR for early language screening is that the automated ABR (AABR) is one of the procedures currently used in the newborn period as part of universal newborn hearing screening. Thus, the addition of a variation of the current procedures might enable expansion of the utility of the procedure in a large swath of the population of newborns. However, this study conducted the speech ABR on children 1 month to 24 months of age, separate from the timing of the AABR in use for universal newborn hearing screening. Brain stem responses to auditory stimuli mature rapidly between birth and 24 months of age; toddler norms are close to adult levels on this measure. The authors were not clear about what features they assessed and whether the results had to be adjusted for child age. If the ultimate plan would be to link AABR and speech ABR, then the study must be conducted on newborn infants. In addition, the outcome measure in this study was collected between 7 and 32 months of age. Children at age 7 months are just beginning to babble; prediction from infant to preschool language skills is very poor. Even testing results at 24 months of age are not good predictors of later language; about half of the children identified as delayed at 2 have caught up to peers by age 3 years [REF]. Thus, in any replication studies, outcomes testing should be conducted at least at age 3 years or older.

The rationale for improved screening for language disorders in this study was to select children for early intervention on the assumption that general provision of such services would be extremely expensive. It is important to note that the methods for improving language outcomes in infants and toddlers are similar for children at high and low risk for language delays, including children with medical complexity such as preterm birth. The key is improving their “language nutrition”.(2) Language nutrition is the combination of favorable environmental factors associated with good language outcomes. It is composed of a high quantity of adult speech directed to the child with a wide variety of sentences and phrases keyed to the child’s interests and attention and provided in warm, loving, and responsive caregiver-child interactions. Improving language nutrition has been found in high quality randomized trials to improve child language outcomes in the toddler-preschool period (3). The data are supportive of the approach for children born preterm (4,5), and children with intellectual disability and autism. (4) Thus, a viable alternative to screening is to provide high quality coaching about language nutrition universally to all parents and caregivers of newborn infants. This sweeping public health goal is the focus of many non-for-profit and non-governmental organizations, many of which operate in communities that may otherwise not receive this important message. The benefit of universal design for this intervention is that ait holds the promise of raising language levels in all children, regardless of early screening results.