Social and Pre-Linguistic Behavior in Infants at Risk of ASD Improves Following Behavioral Intervention

Background: Although some progress has been made in diagnosing ASD in infants, little intervention research for this population has been published.  Interventions designed to increase the social and pre-linguistic behaviors of this populating may be problematical because infants are not expected to verbally communicate, have limited receptive language, and lack a large repertoire of strategies to initiate social interactions.

Objectives: The purpose of this study was to assess whether naturalistic interventions that have been effective with toddlers with autism could be adapted for infants under the age of 1 year. This manuscript presents preliminary data from an intervention program designed for infants that exhibited symptoms of ASD (e.g., failure to respond to name, avoidance of eye contact, lack of social smile, and preference for toys over people). 

Methods: Two infants (4 and 7 months) participated in this study. Both infants had been referred by independent physicians for symptoms of ASD. Motivation-based intervention components shown to be effective for older children (e.g., using child-preferred activities, task variation, and systematic interspersal of acquisition and maintenance tasks) were adapted to be appropriate for infants.  Sessions were implemented by one of the infants’ parents following parent training.  Sessions were once per week for 1 hour. A multiple baseline across participants design was used to evaluate the effects of the intervention on social engagement. Dependent variables included affect, frequency of eye contact between parent and child, and total number of ASD symptoms using the Autism Diagnostic Scale for Infants (AOSI). Affect was rated using measures of happiness and interest. Five point Likert scales were created to identify behavioral indicators of interest (e.g., score of 1 assigned for looking away from parent or activity, score of 5 assigned for alert and active responding) and of happiness (score of 1 for crying or tantrums, score of 5 for laughing or smiling).

Results: Both participants showed stable low levels of interest and happiness in baseline and steady improvement in interest and happiness during intervention. Improvements in affect were maintained at 6 month follow-up. During baseline, both participants rarely engaged in eye contact with parents. During intervention frequency of eye contact was increased. Increased eye contact was maintained at 6 month follow-up.  Mean number of ASD symptoms at baseline for both participants was 12 (range, 10 to 14) and was reduced to 4 for participant 1 and 1 for participant 2 following intervention.

Conclusions: The results of this study suggest that components of naturalistic interventions previously used for older children, also were helpful in increasing positive affect, and improving eye contact in 2 infants referred for symptoms of ASD. The results are discussed in terms of early intervention in infancy and developmental trajectories for children that show early signs of ASD.