Children with autism generally do not learn in the same way that children normally learn, because, in part, they lack the fundamental skills which enable them to acquire and process basic information. They appear to lack understanding of simple verbal and nonverbal communication, are often affected by sensory over-stimulation or under-stimulation, and seem withdrawn in varying degrees from people and the world around them. They are often preoccupied with certain activities and/or objects, which further interferes with their ability to acquire skills and learn from information that is available to them. These difficulties result in significant delays in their development of language, play and social skills, including their failure to notice and learn through imitation of their peers.

Despite the disruption of typical learning processes, behavioral scientists have utilized principles and procedures of learning theory to develop effective treatment methodologies for teaching children with autism. Four decades of research conducted by Dr. Ivar Lovaas and his associates at UCLA, as well as other behavioral researchers, have empirically demonstrated the effectiveness of intensive behavioral treatment for children with autism. In particular, early intervention can significantly improve the abilities of these children to learn and function more adaptively. In his 1987 follow-up study, Dr. Lovaas reported that 17 out of 19 children, who received intensive behavioral treatment, significantly improved their social, self help, play and communication skills, including the development of functional speech. Furthermore, 9 of the 19 children were able to successfully complete first grade in regular education classes and were indistinguishable from their peers on measures of IQ, adaptive skills, and emotional functioning. A 1993 followup study by McEachin, Smith and Lovaas showed that treatment gains were maintained more than six years later and eight of the children continued to progress in regular education classes without support.

The children in this study were three years old and younger when treatment was started. They received an average of 40 therapist-hours per week (some received more that 40 hours, some received less) of individual treatment provided by UCLA undergraduates who were supervised by graduate students and psychologists. Treatment lasted an average of two years or longer.