Vol. 19 • Issue 30
• Page 14
One of the most challenging tasks in working with young children with autism who are nonverbal is teaching vocal imitation and speech production. The two types of intervention generally available are traditional speech therapy and programs based on applied behavior analysis (ABA), including traditional ABA and verbal behavior or applied verbal behavior. A third approach is verbal behavior therapy (VBT).1Traditional speech therapy usually teaches an alternative way of communicating that consists of a few simple manual signs. Children also may learn to select a photo or picture symbol to communicate basic wants and needs. A non-speech oral-motor program may be implemented, and a vocal imitation program that teaches a child to imitate early developing speech sounds often is initiated.
Programs that utilize ABA principles are based on the work of B.F. Skinner, PhD, and were developed by O. Ivar Lovaas, PhD.2,3Dr. Lovaas designed programs to teach a wide range of skills to children with developmental disabilities. Vocal imitation was shaped by reinforcing successive approximations; and sound imitation was shaped to word, phrase and sentence production. Researchers began using Dr. Skinner's analysis of verbal behavior for teaching vocal language to children with disabilities in the early 1990s.4The most popular verbal behavior programs today are the Assessment of Basic Language and Learning Skills-Revised (ABLLS-R) and Verbal Behavior Milestones Assessment and Placement Program (VB-MAPP).5,6They incorporate the fundamental analysis of verbal behavior by Dr. Skinner, who suggested that language is a learned behavior and the basic principles for acquiring other skills apply to the learning of verbal behavior. Instead of using the traditional units of analysis (words, phrases, sentences, and mean length of utterance), he considered the function of verbal responses (e.g., mand, tact, echoic, vocal imitation and intraverbal).
Behaviorally-based vocal imitation programs first teach children to produce echoic responses. Word production is shaped by reinforcing successive approximations. Children then are taught to label and request, followed by intraverbals.
VBT uses ABA principles to shape verbal behavior rapidly.7It differs from other programs by teaching expressive language in the form of requests before teaching receptive language.
The first step is to identify possible reinforcers, such as toys and food, and determine the strongest. Clinicians should present a preferred reinforcer and prompt the child to say a word or sound. Reinforce the child for any vocal response at first to increase the overall number of vocalizations produced, then catalogue the individual sounds produced in therapy and throughout the day and pair them with reinforcers. The child is prompted to imitate a specific sound to get a desired reinforcer. If the child is unsuccessful, prompt a different sound. For example, if a child likes juice and produces "oo" and "ss," prompt one of those sounds. If the child is only able to imitate "ss," assign that sound to the juice.
Sounds are shaped to word imitation using differential reinforcement. Imitation is shaped to spontaneous production of words, phrases and sentences. Approximately 90 percent of nonverbal children with no vocal imitation skills at the beginning of treatment are able to imitate some sounds or word approximations after a few VBT sessions.8Because manding is the foundation for teaching speech in VBT, using a child's motivation as the primary factor in determining the verbal targets for each session is critical. Selecting fun and interesting target vocabulary is important, even as the child progresses to higher-level language. For example, if trying to teach two-word utterances (e.g., agent + action), "Barney + whee" is more interesting and motivating for a child to say than the more generic "boy + slide." Children sustain attention longer when doing fun things and are more likely to produce words and phrases associated with preferred characters.
VBT makes it is easier to target the acquisition of language-based thinking and cognitive skills as well. For example, if a child loves to blow bubbles, the therapist could have several bubble wands on hand. The child will mand for a different bubble toy that looks interesting. This is in contrast to other approaches that might take the bubbles away so the child has to ask for them.
VBT has helped nonverbal children with autism to acquire speech rapidly, increase attention to task, and improve social and cognitive skills. Because target selection initially is child-directed and the presentation is fun and engaging, the therapy now is being used in preliminary studies with infants and toddlers at risk for autism to prevent or decrease symptoms.
1. Drash, P.W., Tudor, R.M. (1990). Language and cognitive development: A systematic behavioral program and technology for increasing the language and cognitive skills of developmentally disabled and at risk preschool children. In M. Hersen, R.M. Eisler & P.M. Miller (eds.), Progress in Behavior Modification, 26: 173-220.
2. Skinner, B.F. (1953). Science and Human Behavior. New York: Free Press.
3. Lovaas, I.O. (1977). The Autistic Child: Language Development Through Behavior Modification. New York: Irvington.
4. Partington, J.W., Sundberg, M.L. (1998). The Assessment of Basic Language and Learning Skills. Pleasant Hill, CA: Behavior Analysts Inc.
5. Partington, J.W. (2006). The Assessment of Basic Language and Learning Skills-Revised (ABLLS-R). Pleasant Hill, CA: Behavior Analysts Inc.
6. Sundberg, M.L. (2008). Verbal Behavior Milestones Assessment and Placement Program (VB-MAPP). Concord, CA: AVB Press.
7. Drash, P.W., High, R.I., Tudor, R.M. (1999). Using mand training to establish an echoic repertoire in young children with autism. The Analysis of Verbal Behavior, 16: 29-44.
8. Jones, L.E. Unpublished clinical data, 1990-2009.
9. Drash, P.W., Tudor, R.M. (2006). How to prevent autism by teaching at-risk infants and toddlers to talk. Presented at Florida Association for Behavior Analysis Convention, September.
LorRainne Jones, PhD, is director of Kid-Pro Therapy Services in Tampa, FL. She can be contacted at firstname.lastname@example.org.