Applied Behaviour Analysis (ABA) is based on the principle that influencing a response associated with a particular behaviour may cause that behaviour to be shaped and controlled. ABA is a mixture of psychological and educational techniques that are tailored to the needs of each individual child to alter their behaviours. ABA involves the use of behavioural methods to measure behaviour, teach functional skills, and evaluate progress.

ABA techniques have been proven in many studies as the method of choice on treating deficits in the behaviours of children with Autism Spectrum Disorder (ASD) at any level. ABA approaches such as discrete trial training (DTT), Pivotal Response Training (PRT), Picture Exchange Communication System (PECS), Self-Management, and a range of social skills training techniques are all critical in teaching children with autism. Ultimately, the goal is to find a way of motivating the child and using a number of different strategies and positive reinforcement techniques to ensure that the sessions are enjoyable and productive.

In all ABA programs, the intent is to increase skills in language, play and socialization, while decreasing behaviours that interfere with learning. The results can be profound. Many children with autism who have ritualistic or self-injurious behaviours reduce or eliminate these behaviours.

ABA helps to establish better to normal eye contact and encourages learning  to stay on task. Finally the children acquire the ability and the desire to learn and to do well. Even if the child does not achieve a “best outcome” result of normal functioning levels in all areas, nearly all autistic children benefit from intensive ABA programs.
 

History of Discrete trial teaching as a therapy for autism spectrum disorder (ASD)

Discrete trial Teaching (DTT) is an ABA-based  therapy which was first developed in the 1970s by Psychologists Ivar Lovaas ,and Robert Koegel, at the University of California at Los Angeles (UCLA).  DTT is based on  principles of ABA and makes use of the idea that when children affected by autism are rewarded for a behaviour, they are likely to repeat that behaviour. In ABA treatment, the therapist gives the child a motivator, such as a question or a request to sit down, along with the correct response. The therapist uses attention, praise or an actual incentive like toys or food to reward the child for repeating the right answer or completing the task.

In a landmark 1987 study, Lovaas and Koegel found that nearly half (47%) of the children who received 40 hours per week of ABA therapy were eventually able to complete normal first-grade classes and achieved normal intellectual and educational functioning by the end of first grade. While none of the children who received the therapy only 10 hours per week were able to do the same.
Other researchers have partially replicated Lovaas's success, among them psychologist James Mulick, PhD, of Ohio State University, who found an association between a form of ABA therapy he calls Early Intensive Behavioural Intervention and improvement in children's IQ scores. Such promising results lead Mulick and other supporters of intensive behavioural intervention to argue that, despite its expense, it should be available to all autistic children.
 

ABA Strategies

ABA therapists work with applied behaviour analysis techniques in order to teach children with autism through intensive one-on-one therapy sessions. ABA can help children at any level on the Autism Spectrum. ABA therapy works on promoting communication, behavioural, social and academic skills.

Specific targets of the interventions are chosen based on the child's individual problems and disorder. Children with autism often exhibit behaviours such as “unwillingness to make eye contact and engage” and a reduction in these compliance behaviours is often the first  intervention target. After behaviour problems are controlled, the intervention aim can shift to dealing with other aspects of autism, such as improving communication and social interaction. In an intensive behavioural intervention program, goals are set and progress is continuously monitored and evaluated. The goals are changed as the child improves or whenever there is a change in the environment requiring a change in the target behaviours.

Treatment is based heavily on functional assessment, information, and family input. Children eventually work many different skill areas that include such skill areas as receptive language, expressive communication, visual performance,  mathematics, and other academic and life learning skills. Behaviour modification and socialization skills are incorporated into a child's program if and when necessary. Therapists use reinforcement and other behaviour modification techniques during the sessions to slowly shape a child's behaviour. The same principles are also used to reduce negative behaviours.  
 

Basic principles of behavioural and educational intervention approaches

Behavioural therapies include specific approaches to help individuals acquire or change behaviours. All behavioural therapies are based upon some common concepts about how humans learn behaviours. At the most basic level, operant conditioning involves presenting a stimulus (request) to a child, and then providing a consequence (a "reinforcer" or a "punisher") based on the child's response.

• A reinforcer is anything that, when presented as a consequence of a response, increases the probability or frequency of that response being repeated. Examples of possible reinforcers for young children may include verbal praise, or offering the child a desired toy.

• A punisher is a consequence that decreases the probability or frequency of that response. Possible punishers for young children may include verbal disapproval or withholding a desired object or activity. The term "punisher" is a technical term used in behavioural therapy and does not imply the use of punishment (physical abuse such as hitting, slapping, spanking, or pinching).

• Reinforcers and punishers are different for each child. Part of operant conditioning approaches is to perform a functional assessment of possible reinforcers or punishers to determine which are most effective in shaping a child's behaviours. While all behavioural therapies have some basic similarities, specific behavioural techniques vary in several ways. Some techniques focus on the prior conditions and involve procedures provided before a target behaviour occurs.

Other techniques focus on the consequence of a behaviour and involve procedures implemented following a behaviour. Still other techniques involve skill development and procedures teaching alternative, more adaptive behaviours. Many different specific behavioural and educational techniques have been used as part of interventions for individual children with autism. These techniques are effective in a wide body of research based on a common set of behavioural and learning principles. Behavioural interventions involve the therapist controlling the activity and/or consequences to shape the child's responses.

ABA Therapy Approaches

A default in social motivation is a characteristic in autism. Children with autism typically lack the motivation to learn new tasks and participate in their social environment. Some traits you may observe when placed in social situations are temper tantrums, crying, non-compliance, inattention, fidgeting, staring, attempting to leave, or unwillingness. The use of ABA therapy can increase the motivational desire in children with autism, therefore, significantly enhancing the effectiveness of the teaching environment.
 

Discrete Trial Training

Discrete trial training consists of a series of distinct repeated lessons or trials taught one-to-one. Each trial consists of a prior, a “directive” or request for the individual to perform an action; a behaviour, or “response” from the person; and a consequence, a “reaction” from the therapist based upon the response of the person. Positive reinforcers are selected by evaluating the individual’s preferences.

Many people initially respond to recognizable or concrete reinforcers such as food items. These concrete rewards are faded as fast as possible and replaced with rewards such as praise, tickles, and hugs. Early intensive behavioural intervention such as the Lovaas program is usually implemented when the person is young, before the age of six. Services are highly intensive, typically 30- 40 hours per week, and conducted on a one-to-one basis by a trained therapist in the family’s home.

Parent training is a necessary part of an effective ABA-based program. The person’s progress is closely monitored by the collection of data on the performance of each trial. After a skill has been mastered, another skill is introduced, and the mastered skill is placed on a maintenance schedule. A maintenance schedule allows for periodic checking so the person does not regress in mastered skills. Discrete trial training is a technique that can be an important element of a comprehensive educational program for the individual with autism spectrum disorder. In some cases, a much less intensive, informal approach of discrete trial training may be provided by a knowledgeable professional to teach specific skills such as sitting and attending.

Pivotal Response Therapy

Pivotal response therapy (PRT), also referred to as pivotal response treatment or pivotal response training, is a behavioural intervention therapy for autism. Pivotal response therapy advocates believe that behaviour connects primarily on two 'pivotal' behavioural skills, motivation and the ability to respond to multiple cues, and that development of these skills will result in overall behavioural improvements.

Initially attempts to treat autism were mostly unsuccessful, and in the 1960s researchers began to focus on behavioural intervention therapies. Lynn and Robert Koegel theorized that, if effort was focused on certain pivotal responses, intervention would be more successful and efficient. As they saw it, developing these pivotal behaviours will result in widespread improvement in other areas. Pivotal Response Theory (PRT) is based on a belief that autism is a much less severe disorder than originally thought.

The two primary pivotal areas of pivotal response therapy involve motivation and initiation of activities. Three others are self-management, feelings and the ability to respond to multiple signals, or cues. Play environments are used to teach pivotal skills, such as turn-taking, communication, and language. This training is child-directed: the child makes choices that direct the therapy. Emphasis is also placed upon the role of parents as primary intervention agents.

The effectiveness of pivotal response therapies have now been proven and ongoing research of its effects on autistic children is being conducted. Pivotal response training is specifically designed to increase a child’s motivation to participate in learning new skills. Pivotal response training involves specific strategies such as
•        clear instructions and questions presented by the therapist
•        child choice of stimuli (based on choices offered by the therapist)
•        intervals of maintenance tasks (previously mastered tasks)
•        direct reinforcement (the chosen stimuli is the reinforce)
•        reinforcement of reason for purposeful attempts at correct respond
•        Turn taking to allow modeling and appropriate pace of interaction

Pivotal response training has proven to be a naturalistic training method that is structured enough to help children learn simple through complex play skills, while still flexible enough to allow children to remain creative in their play.  The child can be reinforced for single or multiple step play. The therapist has the opportunity to model more complex play and provide new play ideas on his/her turn. Research indicates that children with autism who are developmentally ready to learn symbolic play skills can learn to engage in spontaneous, creative play with another adult at levels similar to those of language-age matched peers via pivotal response training .

Reciprocal imitation training

A variation on the pivotal response training procedure for teaching play skills is reciprocal imitation training (RIT). Reciprocal imitation training was developed to teach spontaneous imitation skills to young children with autism in a play environment; however, this intervention technique has also been shown to increase pretend play actions. Reciprocal imitation training is designed to encourage mutual or reciprocal imitation of play actions between a therapist and child.

This procedure includes unexpected simulation in which the therapist imitates actions and vocalizations of the child. A study found that very young children with autism learned imitative pretend play with an adult using this procedure and this play generalized to new settings, therapists, and materials. Several of the children also increased their spontaneous use of pretend play. In addition, the children exhibited increases in social behaviours such as coordinated attention after reciprocal imitation training, suggesting that both the imitative and the spontaneous play had taken on a social quality.

Self-management training

Self-management has been developed as an additional option for teaching children with autism to increase independence and generalization without increased reliance on a teacher or parent. Self-management typically involves some or all of the following components: self-evaluation of performance, self-monitoring, and self-delivery of reinforcement. Ideally, it includes teaching the child to monitor his/her own behaviour in the absence of an adult.

This therapy uses a self-management treatment package to train school-age children with autism to engage in increased levels of appropriate play. In a study children displayed very little independent appropriate play before training, and typically engaged in inappropriate or self-stimulatory behaviour when left on their own. With the introduction of the self-management training package, the children increased their appropriate play in both supervised and unsupervised settings, and across generalization settings and toys. Decreases in self-stimulatory and disruptive behaviours were maintained in the unsupervised environments.

The study shows preschool-age students using self-management training learned new activities using favorite toys that typically required assisted play. Children were prompted to engage in new behaviours with the toys, and were asked to take a token whenever they displayed a variation in the target behaviour. All the children exhibited increases in variability of play after self-management training, with the behaviour maintaining at a 1 month follow-up. Self-monitoring procedures have also been used to increase social initiations while reducing disruptive behaviour and to increase independent interactions with typical peers.
 

Video modeling

Video modeling, like in vivo modeling, uses predictable and repeated presentations of target behaviours; however, these behaviours are presented in video format, thus reducing variations in model performance. Video modeling has been shown to improve various skills in individuals with autism, including conversational speech: verbal responding, helping behaviours, and purchasing skills. This medium has also been claimed to increase vocabulary, emotional understanding, attribute acquisition, and daily living skills.

Video modeling interventions have used both self-as-model and other-as-model methods. In the first performance, individuals act as their own models, and the video is edited so that only desired behaviours are shown. The second and perhaps more essential method of video modeling employs taping other individuals, typically adults or siblings, performing target behaviours.

Video self modeling has been theorized to be more effective than traditional video modeling because it may promote increased attention from the individual, although factual studies have not substantiated this claim. Applications of video modeling as an intervention technique are now being extended to teaching and increasing play in children with autism.

ABA therapy used at the clinic

All behaviours, whether they are being observed or taught, can be broken down into 3 parts;

• Antecedent (A) - what triggered a behaviour or what happens before the behaviour,
• Behaviour (B) - the behaviour itself, and
• Consequence (C) - what happens after the behaviour.

The consequence is whatever the behaviour accomplishes, for example it can be getting attention (negative or positive) or relief of stress. The consequence is not always obvious, especially in the case of stimming behaviour (odd behaviours the child does such as arm flapping or repetitive actions), which is why keeping data is helpful to identify what the function of the behaviours are, as well as what triggers them.

During ABA assessment, the Autistic child’s behaviors are carefully observed to assess:

• exactly what behaviours are performed by the child
• when  these behaviours are performed
• at what rate  the behaviours are occurring
• what happens before and after the behaviours.
• what purpose does the behaviour serves

Skills that are to be promoted are broken down into small sequential steps. The ABC principles of behaviour intervention are used to teach the child each step, :

• A  (antecedent) – Each instruction is given clearly, in as few words as possible. Assistance is provided; for example prompting through demonstration or physically guiding.
• B  (behaviour) –  An appropriate behaviour is observed,
• C  (consequence)– A consequence is an outcome that will reward the child and increase the likelihood that the behavior will be repeated again in the future, also called a positive reinforcer.

This "ABC" process is repeated frequently for each behaviour both in structured teaching situations and in the course of everyday activities using PRT techniques.

1. Instructions are given to emphasise metacognition (learning how to learn). In this case learning how to listen, to watch, to imitate, to ask and do.
2. As the child's learned behaviours improve, the structured guidance is systematically reduced and the prompts are used less frequently and eventually faded out. This so that the child learns to perform the trained behaviour independently.
3. It is also important to change the context of teaching (different people giving the antecedent, more people around, different situations, etc.) in order to generalise the learned behaviours.
4. When each behaviour consisting of single sequential steps are acquired, the person is taught to combine them to produce more complex behaviours.
5. Problematic behaviours are not reinforced, instead the child is consistently redirected to engage in appropriate behavior.
6. The child’s responses during each step is meticulously recorded. The information is later used to determine if the child is progressing at an acceptable rate. If progress is not satisfactory, the learning steps are analysed for possible flaws and the program modified.

The ABA Therapist

ABA therapy is highly intensive and requires the therapist to be pleasant, knowledgeable, consistent, patient and empathetic. In addition, the therapist must be capable of objectively observing and analysing the behaviours, design appropriate ABC steps and implement them effectively.

• A psychologist at the clinic designs an ABA program and monitors its application by parents and therapists.
• The behaviour of the ABA therapist should also be observed regularly. Initially to train the therapit and then less frequently and as needed to ensure that ABC procedures are being applied correctly and safely.
• Recording the behaviours of both the child and the therapist is useful.
• There must be empirical observed evidence that the program is working.
• Even experienced behavior therapists need this form of feedback.
• The recorded data informs us about the effectiveness of the procedures applied, and how to improve the effectiveness of the intervention and allows the intervention to adapt as the child grows and changes.