Infant Siblings of Children with Autism: Results of a Parent-Child Intervention

Background: As prospective studies of infant siblings at increased genetic risk for Autism Spectrum Disorder (ASD) begin to identify infants who show signs of atypical social and communication development within the first year of life (Cassel et al., 2007; Zwaigenbaum et al., 2005), there is a critical need for the investigation of evidence-based treatments suitable for an at-risk infant population.  Pivotal Response Treatment (PRT; L.K. Koegel et al., 1999), an evidence-based treatment developed for older children with ASD, may be particularly well-suited for treatment of infants at risk for ASD, as it has been shown to improve social communication by addressing core deficits in social motivation (R. L. Koegel et al., 1987). 

Objectives: The present study investigates a developmentally-based adaptation of PRT to improve the frequency and spontaneity of critical prelinguistic communication behaviors in 12-month-old infants at risk for ASD.

Methods: Three 12-month-old infants, enrolled in a prospective study of infant siblings of children with ASD, and their mothers were provided with 10 hours of parent-child intervention over 3 months.  Each 1-hour session included instruction and clinician modeling of motivational behavioral strategies to increase the frequency and complexity of the infant’s nonverbal communication, as well as opportunities for the parent to practice the techniques with in-vivo feedback.  A multiple-baseline design across participants was employed.  Dependent measures included frequency of child communication, communication spontaneity, and parent fidelity of implementation of treatment components. 

Results: Relative to baseline, results indicated immediate increases in frequency and spontaneity of communication following introduction of the parent-child intervention.  All three parents learned to independently implement the procedures with at least 75% fidelity during the course of the brief intervention.  Child frequency of communication during interactions with the parent increased as parent fidelity of implementation improved.  A post-treatment questionnaire indicated high levels of parent satisfaction with the procedures. 

Conclusions: Results of this preliminary study provide support for 1) the feasibility of a developmentally-based adaptation of PRT, 2) the efficacy of these procedures in improving the frequency and spontaneity of prelinguistic communication in children at risk for delays in social-communication development, and 3) the efficiency of the parent education approach in teaching parents to implement procedures with fidelity.  Implications of these findings for understanding developmental trajectories and treatment needs of infants at risk for ASD will be discussed, and areas for further investigation will be proposed.