What is Autism?

Autism is a profoundly handicapping developmental disability.  There is a spectrum of severity of the disorder, and some children are more severely affected than others. According to statistics released by the National Institutes of Health in 2004 and the Center for Disease Control and Prevention in 2001 this disease is diagnosed in one of every 166 children born in the United States. More recent studies have shown an even higher incidence.

Autism appears during the first three years of life. Some children with autism seem to develop normally for 12-24 months, then lose all their skills over a period of days or months. Others never acquire skills to begin with.  Children with autism are diagnosed using specific clinical criteria showing severe deficits in communication, social interactions,  and the presence of “restricted, repetitive, and stereotyped patterns of behavior, interests, and activities”. Some examples of these kinds of repetitive behaviors include repetitive actions or vocalizations, such as swinging strings, flapping hands, repeating movie dialogue, fascination with parts of objects, and insistence on set routines to a point far beyond what a typical child displays. Children with autism and pervasive developmental disorder, not otherwise specified (PDD –NOS,  also an autistic spectrum disorder)  have a very poor prognosis without treatment. In the past, the majority of people with autism lived in institutions by the time they were adults. With the advent of ABA treatment many of these children now have a hope of improved functioning, and some achieve the skills they need to live independently as adults. The prognosis for any individual child cannot usually be determined before several months or years of intensive treatment, but research indicates that overall outcome appears to depend on the degree of intellectual impairment and the intensity of  treatment. Research into the physical causes and medical treatments of autism continues, but to date there is no proven medical cure.

Asperger’s syndrome is also an autistic spectrum disorders. The large majority of research on ABA methods for people on the autism spectrum has been done with children with autism and PDD-NOS, and most intensive ABA programs serve primarily children with those diagnoses.

What is ABA? 

Applied behavior analysis (ABA) is the science of human behavior. Behaviorists define learning as the process of acquiring new behaviors from experience. Learning is one of the skills ABA addresses. ABA is ethically bound to address the behaviors that make a person able to be as independent as possible. Some examples of behaviors that can be taught are speaking, playing, reading, writing, socializing, imitating gross and fine motor skills, and very importantly, skills that teach children how to learn in generalized environments.  ABA also addresses functional skills such as dressing, toileting, eating with utensils, and many other skills. All of these skills are addressed by looking at basic, research proven behavioral principles, from which the behavioral techniques most likely to be successful for each behavior needed by each child are derived.   

ABA is used to help people, including children with autism, is many ways. ABA is used to teach new skills, to increase the use of skills the child already has, to ensure that the child uses they skills he or she has in many different circumstances, and to reduce inappropriate behaviors.

ABA is a science. The procedures are based on the data for each child. They must produce replicable results.   The behaviors addressed must be defined in an objective fashion. An objective definition is one that is observable and quantifiable. A behavioral definition may include phrases such as “pointing to the letter “A” in a field of three when asked “Where is the letter A?” A non-behavioral definition may be worded differently, such as “will comprehend letter identification concepts.”

This does not mean that behaviorists do not recognize the existence of things we cannot see, such as anger, happiness, and understanding. But as scientists we must stay within observable definitions of behavior.

ABA and Autism

ABA is a science used with all populations, including non-handicapped people.  It has been shown to be an extremely effective intervention for people with autism, especially young children. Decades of research have shown significant gains in children with autism treated with intensive ABA programs. The most famous research on this treatment approach is probably the research published by Lovaas in 1987. This showed that with intensive (40 hours per week) ABA treatment, 47% of the children tested with normal IQ scores and functioned independently in regular education with their typically developing same-age peers by the end of first grade.

Six years later, nine of the children were reevaluated. This research found that not only had treatment gains been maintained, they had reached a status where even when tested by trained professionals the treated children were not distinguishable from their typically developing peers.

Research has also been done on the cost benefit ratio of ABA when used with young children with autism. ABA programs are expensive. ABA programs requires intensive therapy for many hours per week (at least 25-40) to provide lasting benefits. In addition to the therapist hours the quality and amount of the supervision have been identified as crucial components of effective programs. Research has shown that children who receive no intensive ABA treatment are likely to cost the taxpayers an average of 2 million dollars over the course of their lifetimes. Children who show some treatment effect may cut that in half, and children who become able to function normally are likely to have no cost to the taxpayers (and in fact become tax-payers themselves) beyond the costs of their program.

Many decades of research have been done on the effectiveness of ABA, as well as the relative lack of effectiveness of other interventions for young children with autism. To date it is the only consistently  replicated effective treatment for children with autism, and has been endorsed by many researchers as well as government agencies as the “best practice” approach for these children.

Click on the link at left or here to view a short video illustrating ABA techniques, "Towards the Light." This video may take a few minutes to download and begin playing.

What is Discrete Trial?

Discrete trial training is one of the instruction procedures frequently used in ABA  programs. Discrete trial training is often abbreviated as DTT. Most of the time when a therapist is “in the chair” with a child at a table, discrete trial will be the method used to teach. Other methods may be used as well, including (but not limited to) PECS, schedule strips, functional skills training, and incidental teaching. All behavioral methods, including discrete trial, use the same principles, including prompting, fading, and reinforcement.

Discrete trial is the teaching methodology that teaches one small piece of information at a time. Each discrete trial has three basic components – a stimulus (or antecedent) , the behavior (or response), and the consequence of either a reinforcer or the lack of a reinforcer depending on whether the child responded correctly.

An example would be in a lesson (also called a drill) such as receptive object labels:

• The label being taught (we will use apple as our example) requires two parts for the stimulus.
• The apple itself must be present and in the child’s view. This is called “in the field.” Generally there will be several objects in the field to insure that the child is discriminating the word “apple” and not just indicating whatever object happens to be in front of him.
• The stimulus (or antecedent) is the presence of the apple and the words “touch apple.”
• The desired response (or behavior) is the child independently touching the apple.
• The appropriate consequence is the reinforcement of the desired response. If the child does not give the desired response the appropriate consequence is the ending of the trial without reinforcement. The child will then be helped to respond correctly. This is called a prompt.

Discrete trial training is used to teach individual pieces of information. Once enough of these individual or discrete units are learned, entire concepts can be acquired. In the apple example above not only is the word apple being taught, but the underlying concept that a sound can symbolize an item is also being taught. Once several discrete skills are taught in many given concepts (for example – the child may be taught to imitate 5-10 distinct gross motor movements) then the targeted skill will be imitating novel, or previously untaught, gross motor movements. This tells us that not only can the child imitate several skills, but that he or she can imitate any gross motor skill.

Discrete trial can be used for more advanced skills as well as simple skills. Even complex social skills such as determining what behavior changes should happen in response to another person’s facial expression can be started in a discrete trial format, and then generalized to more unstructured “real world” environments.

What is Functional Skills Training?

Functional skills are traditionally those taught to help with self-help and other areas that are not practical to teach in a strictly discrete trial manner. Some examples of these are toothbrushing, toileting skills, dressing, etc. Most functional skills are taught in chains of smaller steps, and each step in the chain is targeted as the child learns the skill. Functional skills training teaches many skills in long chains, as opposed to discrete trial training, which teaches one discrete skill at a time.

Page Updated 6 August 2007