| dc.description.abstract | Samenvatting: Autism Spectrum Disorders occur in 6 of 1000 children. The disorders present themselves in substantial social, communicative and behavior problems. Ferster (1961) was the first scientist to describe autism from a behavioral perspective. Inspired by this approach, Lovaas developed a therapy based on Skinners principles of operant conditioning. The first results of this intervention Applied Behavior Analysis (ABA), were amazing. They suggested a certain plasticity of autism, with a chance of recovery (Lovaas, 1973; Lovaas, 1987). A lot of research on ABA was performed. The intervention developed to be the most successful en most well-established intervention for children with Autism Spectrum Disorders (ASD) in the USA.
However, in the Netherlands ABA is less well-known and less well-established. Research on ABA in the Netherlands is rare. The current study was performed in order to study the effectiveness of ABA conducted by the Dutch ABA-instituut and ABA-centrum. The amount of inappropriate behavior, appropriate behavior and use of language was measured by coding video´s of the first training (T1), a training a half year after the first one (T2) and a year after the first one (T3). Appropriate behavior was defined as behavior promoting social contact and leading to social reinforcers. Inappropriate behavior was defined as behavior typical of children with ASD, and hindering social contact and communication. Use of language was defined as being able to use language to be understood and understand in order to react appropriately to the social environment. Fifteen children participated, their age ranging from 2;7 to 15;7 years at the start of the intervention. The amount of 1:1 ABA-training varied between six and forty hours per week.
A significant increase in appropriate behavior and a decrease in inappropriate behavior was found at T3 compared tot T1. Use of language increased with 72 percent between T1 and T2, which was obviously significant, even as the difference between T3 and T1. Of the verbal operants used to measure ‘use of language’ independently, ‘receptive language’ appeared to have increased the most. Amount of training influenced the decrease of inappropriate behavior, but not the increase of appropriate behavior or language. No effect of age was found.
Despite flaws in the current study which made it difficult to find significant effects, after a years of ABA as offered by the ABA-instituut and ABA-centrum, a significant decrease in inappropriate behaviour and increase in appropriate behaviour and use of language was found in children with ASD. A bigger sample, a control condition, controlled training situations, video’s of the children at home and at school, standardized measures and parent interviews are needed to study the effectiveness of ABA more extensively. Follow-up studies will be needed to study the long-term effects of ABA on the behavior of children with ASD. | |
