A Comparison of the Effect of Object and Gesture Imitation Training on Language Use in Children with Autism

Background: Research indicates that children with autism have deficits in imitation that may underlie the abnormal development of other social-communicative behaviors.  It has been shown that imitation is associated with the development of language (Bates et al., 1988).  Reciprocal Imitation Training (RIT) is a developmentally-based imitation intervention that teaches imitation within a social-communicative context. RIT is effective at teaching children with autism spontaneous, generalized object and gesture imitation.  In addition, across studies, changes in object (Ingersoll & Schreibman, 2006) and gesture (Ingersoll, Lewis, & Kroman, 2007) imitation were associated with concomitant increases in verbal imitation and spontaneous language, suggesting that teaching non-verbal imitation can improve language behaviors.  Research suggests that object and gesture imitation skills are independent and that gesture imitation is more closely associated with language skills (Stone, Ousely, & Littleford, 1997).  However, it is not clear if teaching gesture imitation to young children with autism improves language more than object imitation.

Objectives: This study examines 1) whether children are more likely to engage in verbal imitation during object or gesture imitation training using RIT, and 2) whether adding gesture imitation training improves the overall rate of appropriate language use in children with ASD who have already been participating in object imitation training.

Methods: :  Four children with autism participated in this study. The children ranged in age from 35 to 47 months at intake with mental ages ranging from 22 to 30 months on the Bayley Scales of Infant Development, 2^nd edition (Bayley, 1993).  Expressive language age ranged 21 to 23 months (Total language 18 to 21 months) on the Preschool Language Scale Fourth Edition (Zimmerman, Steiner & Pond, 2002). Participants received training in object and gesture imitation using RIT in three, 20-minute sessions per day, three days a week for 10 weeks.  This study used a rapidly alternating treatments design to examine whether teaching object or gesture imitation using RIT leads to greater use of verbal imitation.  It also used a multiple-baseline design across the same children to examine whether adding gesture imitation training improves the overall rate of appropriate language use in children with ASD who have already been participating in object imitation training.  

Results: Preliminary results indicate children were more likely to use verbal imitation during gesture than object imitation training.  Further, children showed greater improvements in their use of appropriate language after gesture imitation was begun.

Conclusions: Teaching gesture imitation using naturalistic behavioral treatment to child diagnosed with autism appears to directly increasing language use. These findings may have important implications for both language development and early intervention.