The trend toward early diagnosis and the push for early intervention for children with autism spectrum disorders (ASD) indicate a need to predict symptoms at a very young age. Despite the commonality of symptoms associated with ASD, there are considerable differences in the early childhood development of individuals who are diagnosed with autism.
There are three behaviors that could potentially predict the future communicative and intellectual abilities of young children with ASD: joint attention, imitation, and object play.
Joint attention is sharing the attention of another person in an activity or event, or in looking at an object.
Imitation is repeating movements or sounds made by another person.
Object play is playing or interacting with an object, such as a toy.
Such behaviors emerge and develop rapidly between one and two years of age in typically developing children, but young children with autism are challenged by them.
This study is based on the assumption that joint attention, imitation, and object play are specifically linked to later cognitive and language development in infants with autism. That is, infants who do not show those behaviors are more likely to have intellectual and language difficulties.
The study used home videos of infants who were later diagnosed with autism to find correlations between infant behavior and autism in childhood. Researchers aimed to measure overall levels of joint attention, imitation, and object play, as well as whether those levels changed over time. They tried to determine how much these behaviors are related to the language and intellectual functioning of those same children at 3 to 7 years old.
Home videos were collected from the parents of 29 children with ASD. The videos showed the children from birth to 2 years of age. Each video was divided into 40 time intervals. Two systems developed by the researchers were used to measure the predictive behaviors (joint attention, imitation, and object play) in the videos. The first system was the Object Play Coding Scale (OPCS), which calculated the number of time intervals where the infant did object play. The second system was the Naturalistic Observation Schedule of Infant/Toddler Behaviors (NOSIB), which provided a count of intervals where the child showed joint attention or imitation behaviors. Since there were 40 time intervals for each video, the number of times each behavior could occur ranged from 0 to 40. Additionally, each instance of a predictive behavior was rated on a scale of 1 to 5 for developmental maturity.
The communication ability of the children at their current age was measured with the Vineland Adaptive Behavior Scales (VABS). Their intellectual ability was measured with the Mullen Scales of Early Learning (MSEL). Parents were asked to report the age when their child began to walk.
Statistical models were used to compare the age of the child, the predictive behavior, and the age the child began walking to their current communication skills and IQ.
Joint attention behavior in infancy was not as heavily connected to the child’s rate of development as imitation and object play. An earlier walking age did correlate to higher language and cognitive skills, but it was not correlated to the child’s rate of development. High VABS scores were directly related to higher instances of predictive behaviors, as was IQ.
Studies of young children with ASD have consistently found impairment in joint attention, imitation, and object play compared to typically developing children or children with other developmental disabilities. This research confirms these findings and extends them to younger children. This study suggests that children who are later diagnosed with autism experience delays in the development of skills in these areas over the first two years of their lives. Although they continue to acquire these skills during this time period, they are acquired at a slower rate.
The results of this study support the important role of joint attention, imitation, and object play during infancy in predicting later development. Children with autism who have higher levels of skills in these areas are more likely to have stronger communication and intellectual skills in the preschool or early school age range.
This Research Brief is based on the article: Poon, K.K., Watson, L.R., & Baranek. G.T., & Poe, M.D. (2012). To what extent do joint attention, imitation, and object play behavior in infancy predict communication and intellectual functioning in ASD? Journal of Autism and Developmental Disorders. 42(6), 1064-1075.
This research was supported by a grant from NICHD (R01 HD42168). We thank the families whose participation made this study possible. For more information about The Sensory Experiences Project please visit our website: http://www.med.unc.edu/sep
North Carolina at Chapel Hill