Early Vocal Development in Tuberous Sclerosis Complex Predicts Language but Not Autism Outcomes

Area of Science:

• Pediatric neurology
• Developmental pediatrics
• Speech and language pathology

Background:

• Language impairments affect a significant majority of individuals with tuberous sclerosis complex (TSC), often leading to delayed evaluations.
• Infant vocal behavior, specifically the canonical babbling ratio (CBR) and volubility, are key indicators of early language development.
• Previous research indicated low CBR and volubility in infants with TSC, necessitating further investigation.

Purpose of the Study:

• To further characterize canonical babbling ratio (CBR) and volubility in infants with TSC.
• To assess the predictive power of CBR and volubility for autism spectrum disorder (ASD) and language outcomes in TSC.
• To determine if CBR's predictive contribution is independent of other known language predictors.

Main Methods:

• Analysis of 202 infant recordings at 12 months of age from individuals with TSC.
• Utilized linear regression to predict language outcomes based on vocal measures.
• Employed stepwise multiple regression and logistic regression to evaluate predictive capabilities for language and ASD, respectively.

Main Results:

• Infants with TSC exhibited lower CBR and volubility compared to typically developing infants.
• CBR significantly predicted language outcomes at 24 months in infants with TSC, outperforming other known predictors.
• Neither CBR nor volubility demonstrated predictive capability for autism spectrum disorder (ASD) in this cohort.

Conclusions:

• The canonical babbling ratio (CBR) shows potential as a valuable tool for the early identification of language impairments in infants with TSC.
• Early vocal assessments may facilitate timely interventions for language development in this population.