Association for Behavior Analysis International

Recent research has shown that infants who later develop ASD have a strong preference for sensory stimuli in contrast to typically developing children, who have a strong preference for social stimuli. For infants with a preference for sensory stimuli, geometric patterns and non-speech sounds in the environment select their attention and these sensory stimuli likely function as powerful reinforcers for the behavior of the infant. As the infant grows older, they will not only attend to sensory stimuli, they will also exhibit repetitive and stereotyped behaviors to produce additional sensory reinforcement. The affinity for sensory stimuli at the cost of social stimuli may result in a negative spiral of acquiring social reinforcers and social behaviors. Consequently, the infants fail to learn by imitation and to achieve developmental milestones such as joint attention, verbal skills, and theory of mind. Typically developing infants, in contrast, will attend to the eyes and the voices of the caregivers, because these stimuli function as powerful reinforcers. These social reinforcers select additional social and verbal skills such as social smiling, imitation, joint attention and pragmatic language.

An application for a tablet to assess responding to social stimuli and geometric stimuli was developed. Two blurred visual stimuli, one social and one geometric, were presented simultaneously on the tablet screen. Whenever one of the stimuli was touched, it becomes complete for 2 seconds before getting blurred again. Dependent variable was number of touches on each type of stimuli, to determine the reinforcing property of the social stimuli and the geometric stimuli. Results showed that children with autism, on average, responded most frequently to the geometric stimuli and less frequently to the social stimuli, as compared to typically developing children and children with intellectual disabilities. We hypothesize that if social stimuli function as reinforcers for the behavior of an infant, the social reinforcers will select social- and verbal behavior, such as looking at adults, imitation, joint attention, social communication and theory of mind behavior. If sensory stimuli (such as geometric forms) function as a more potent reinforcer for an infants behavior as compared to social stimuli, the sensory reinforcers will select stereotyped and repetitive behavior rather than social and communicative behavior. Indeed, the presence of stereotyped behavior and the lack of social skills and communication define autism.

This presentation begins by reviewing recent studies examining infants preference for social stimuli and sensory stimuli. Using eye-tracking technology, studies have shown that infants who later develop ASD spend less time looking at eyes and listening to the voice of caregivers, as compared to typically developing infants. Moreover, research has shown that infants who later develop ASD show preference for geometric forms, as compared to typically developing infants and infants with learning delays. Research from our lab shows that children with ASD will not only prefer looking at geometric stimuli, but will also show increased responding when the consequence for responding is viewing geometric stimuli as compared to social stimuli, as compared to typically developing children and children with learning delays. Hence, sensory stimuli seem to function as a more powerful reinforcer for the behavior of infants developing ASD as compared to social stimuli. Sensory reinforcers will likely select a different behavioral repertoire in an infant as compared to social reinforcers. Sensory reinforcers will select stereotype behavior and other non-nonsocial behavior consistent with ASD, whereas social reinforcer will likely select attention to faces and human voices, imitation, joint attention, communication and other more advanced social skills.