PROJECT ABSTRACT
The proposed study (PETAL: Promoting Early intervention Timing and Attention to Language) aims to
determine the timing of a parent mediated intervention among infants with Increased Likelihood for Autism
(ILA) (at risk for autism by virtue of having an older sibling with autism) on communication and language
outcomes at 24 months. ILA infants are likely to experience delays in language with ~ 40% at risk for language
delay and/or later diagnosis of ASD. However, interventions for ILA infants remain rare and none of the current
interventions explicitly focus on language or include many infants from lower socioeconomic circumstances
who may be at even greater risk for language delays. Although enthusiasm is high for very early interventions
due to known brain plasticity in the first years of life, we do not know WHEN or with WHAT MEASURES to
determine if an intervention is appropriate for ILA infants who are not yet showing signs of autism or delay.
The overarching goal of the proposed study is to determine the optimal timing of very early
intervention for ILA infants (starting at 9, 12 or 15 months) that explicitly targets communication and
language. We will use a battery of brain- and behavioral-based markers to identify the combination of change
in language, behaviors and brain measures that predict expressive language outcomes at 24 months. 140 infants
beginning at 6 months of age will participate at two sites, Los Angeles and Boston areas with many from
traditionally marginalized and minoritized families. All parents will receive infant developmental monitoring
beginning at 6 months, and then using a four-phase, sequential multiple assignment randomized trial design,
parents will receive augmentation with a specialized language coaching intervention at 9, 12 or 15 months; all
infant parent dyads receive coaching by 15 months. A diverse sample of dyads will be recruited; assessments
will occur at home at 6-,9-,12-,15-, 18- and 24-months using brain-based EEG measures, social-
communication, and language measures. Intervention support will be provided by clinicians remotely. The
study addresses key questions of whether earlier intervention is better on primary language and secondary
outcomes of social communication behaviors that support language development (e.g., joint engagement,
vocalizations, words, object play) and which measures will inform the ideal transition to intervention on
language outcomes at 24 months. Moreover, using LENA to capture the home language environment, adult
word count and conversational turns will be examined for mediation on language outcome. Results of this
study have potential for determining when (9 vs 12 vs 15), and based on which measures (brain, language, or
their combination), to augment parental support with a specialized parent-mediated coaching intervention.