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ABA Handbook

What is ABA?

Applied behavior analysis is the extension of operant (focus on observable behavior in individuals) methodology to the modification of human behavior.

History of ABA (very brief):

  • Watson & Raynor (1920): Conditioned a phobic reaction in an I I month old child.
  • Hull (1943): Stimulus- response learning theory
  • Skinner (1953): Extended operant principles to human problems. Criticized the psychoanalytic approach and adopted a philosophical position of radical behaviorism (only observable behavior can be the subject of scientific investigation).
  • Eysenck(1959): Defined behavior therapy as an applied science (as opposed to psychotherapy).

Behavioral treatment applied to autism focuses on increasing behavioral deficits and decreasing behavioral excesses.

'ABA' is a general term. There are several different behavioral treatments for many disorders including autism.

Behavioral Treatments/Programs for Autism

Like behavioral treatments for other disorders, behavioral treatments for autism focus on observable, measurable actions of the individual. It is assumed that behaviors are under control of the environment Change is accomplished by manipulation of that environment.

There are many behavioral treatment programs for people with autism. Each program has many variations and improvements are consistently being attempted, often successfully. Major differences between programs are based on philosophical differences and include variations in intensity and specific behaviors targeted for intervention.


Review of Principles of ABA

The "ABC's" (Antecedents, Behaviors and Consequences)

A Antecedents are the events that happen before the behavior occurs.

B Behavior is the specific way the child acts.

C Consequences are the events that happen to the child immediately following the behavior


A Patrick is in speech therapy. His speech therapist tells him to "sit down"

B Patrick hits the therapist.

C The therapist takes him back to his classroom.


  1. What is Behavior?
    • Anything we do or say constitutes a behavior. - examples: walking, talking, eating, sleeping, shopping, thinking ......
    • Behaviors are acquired (learned) and maintained throughout our fives through our daily interaction with our environment and other people.
      • -note: we are born with some basic behaviors which are called reflexive behaviors (e.g. crying, sucking, motor reflexes, etc.). these are maintained and changed through interaction with the environment.
    • Behaviors are all functional in some way.
      • -We might not understand what the function is and we might not like it! Often, behaviors serve as a means of communication.
    • Behaviors interfere
      • -Undesirable behaviors interfere with learning appropriate behaviors.
      • -Inappropriate behaviors can replace appropriate behavior
      • -Some common interfering behaviors include tantrums, self-stimulatory, self-injury, aggression, etc.
  2. Defining Behaviors

    In order to change behaviors they MUST be well defined!

    • Good definitions break behaviors down into their simplest components. They describe details of the actions observed.
      • Bad definition: My child throws a tantrum when he gets mad
      • Good definition: My child sits dawn on the floor, kicks his legs, and screams when I say "no " to him.
    • 2. Good definitions of behavior are important so we can measure the behavior.
  3. Measuring Behaviors

    Measuring behaviors allows us to determine whether or not a behavior is increasing, decreasing or staying the same.

    Measurement is important to let us know if a program is effective.

    • 1. Two major ways to measure behavior include Frequency and Duration.

      Frequency: The number of times the behavior occurs in any given time interval.

      Duration: The amount of time that passes from the beginning to the end of the behavior

    • 2. Frequency and duration can be recorded a number of ways: data sheets, video probes, memory (not very reliable).
    • 3. Behavior can be recorded over varying time periods. These time periods can vary from a small interval (I hour) to all day depending on the nature of the behavior.
      • note: very frequent behavior may be measured just one hour per day the same time each day and/or same circumstances.
  4. Measurement over the course of intervention occurs during baseline, treatment, post treatment and follow-up.
    • Baseline is the rate of behavior prior to the intervention
    • During treatment data are taken to assess progress
    • Post treatment data are taken to assess effectiveness
    • Follow-up data are taken to assess generalization and maintenance of treatment gains

Graph here


  1. What is an antecedent?

    An antecedent is the event that happens just prior to occurrence of the target behavior. It includes: General circumstance- the circumstances that set the stage for the behavior (e.g. at breakfast, at speech therapy) Specific trigger event (e.g. "no", a command)

  2. Why is the antecedent important?

    Identification is important for 2 reasons:

    1. It allows you to predict when the behavior may occur
    2. By changing the antecedents, you can change the behavior
  3. Is there always an antecedent to a behavior?

    There is always an antecedent however, it is not always readily identifiable (e.g. with self-stim)



  1. What are Consequences?

    Consequences are events that follow a behavior. They include Reinforcers, Punishers and neutral events.

    • Reinforcer: Increases the probability that a behavior will occur again
      • A behavior is increased to get access to a positive reinforcer
      • A behavior is increased to get rid of a negative reinforcer (e.g. seat belt buzzer)

    • Punisher: Decreases the probability that a behavior will occur again (not to be confused with negative reinforcer)
    • Neutral consequence: does not change the probability of occurrence of a behavior

    In general: Behaviors followed by pleasant consequences are more likely to occur again. Behaviors that are not followed by pleasant consequences are less likely to occur again.

    This principle is important to remember when you are working with your child. If you are teaching a skiII and the behavior is not increasing, you may not have a powerful reinforcer. If you are trying to decrease a problem behavior and it continues to increase, you may not have an effective consequence.

  2. Behaviors are generally maintained by 3 general types of consequences (see A-B-C Pattern examples 1-3):
    1. Attention (scenario 3)
    2. Escape or avoidance of an aversive event (Scenario 2)
    3. Tangible rewards (play, candy, beverage, etc.) (Scenario 1)

    By examining and understanding antecedents and consequences maintaining behaviors, we can change them to alleviate problem behaviors and increase desired behaviors.


The next two pages contain vignettes. Identify:

  • Antecedents (General,specific trigger)
  • Behavior(s)
  • Consequence(s)

How would you treat (behaviorally) the problem?



Scenario I

Paul's dad takes him to the grocery store. In the store Paul sees a toy he wants but his dad tells him no. Paul throws himself on the floor, kicking and screaming. His father, quite embarrassed by the tantrum, buys the toy for Paul.

Scenario 2

Sarah screams and bites her hand whenever her parents try to teach her a new activity, pointing to pictures. As soon as she begins to scream, they terminate the teaching session.

Scenario 3

Matthew jumps up from the table at mealtimes and runs around the house. One of the family members always chases after him and brings him back to the table.



A-B-C Pattern Examples

Instructions: For each example, identify the antecedent(s),..specific behavior and consequence maintaining the inappropriate behavior.

(1) Rachel's father asks her to pick up her toys and Rachel refuses by saying "no." Her father asks two more times without success and then he picks up the toys himself.

(2) Jackie is able to dress herself and does so independently without making a fuss on the weekends and when changing into her pajamas at bedtime. However, every weekday morning she fusses and whines as her mother stands over her urging Jackie to dress quickly before the school bus comes. Her mother, annoyed, helps Jackie finish dressing as the bus pulls up in front of the house.

(3) Nicholas' father fixes him a well-balanced dinner of foods his teacher reports he will eat for lunch at school. However, at home, Nicholas refuses to eat pushing his plate away. His father, not wanting him to go hungry, gives Nicholas his favorite food, jello.

(4) Tammy often rocks and bangs her head against the wall as her mother attends to her new baby sister. Tammy's mother reacts to this by immediately hugging and attending to Tammy, often offering her food and toys.

(5) Archie has a language delay but has been observed to use some appropriate language at school. Archie's parents have not been able to elicit the same language at home. Before giving Archie something he clearly wants, his parents prompt him to use his words to ask for it. Archie responds by tantrumming until his parents finally give him what he wants.

(6) Kathy's parents have decided that it is time she learn to eat with a fork and spoon. To start out, they have decided to teach her during dessert time. After Kathy finishes eating her dinner with her hands, she is presented with a bowl of ice cream and a spoon. Her parents put the spoon in her hand, and guide it toward her mouth. Kathy reluctantly takes the first bite then shoves the bowl off the table as her parents prompt her to take another. Kathy's parents remove the bowl, clean her up then continue their typical evening.



 Behavioral Assessment

  • Assessment in General

    Theoretical persuasion of the service provider influences what is emphasized in assessment. Areas that are considered theoretically important for intervention are considered most important for assessment. At one end of the spectrum Behavioral theory emphasizes an assessment based on behavioral excesses and deficits. At the other end of the spectrum Psychodynamic theories emphasize an assessment of underlying causes for observable behaviors. There are other schools of thought which utilize combined theoretical approaches and observation to determine relevant areas to assess in an individual with autism. Once assessments are conducted, analysis of those data are completed to further formulate goals for intervention.

    Initial assessment is important for the following reasons:

    1. It is the basis for determining future areas of intervention
    2. It provides a baseline from which to determine the effectiveness of intervention
  • Types of Assessment
    1. Standardized assessments (IQ, Language, Adaptive behavior-Vineland, Developmental, Family assessments)
    2. Direct observation (video recording)
    3. Interviews (Parents, Teachers, Peers)
    4. Physical assessment (Neuro, immune system, etc)
  • Behavioral Assessment

    Behavioral assessment utilizes available information from many sources (See types of assessment above). Information is categorized as behavioral excesses and deficits.

    Behavioral excesses: Behaviors that occur too frequently and/or with too much intensity. Examples are self-stimulatory behaviors, aggression, tantrums. Behavioral deficits: Behaviors that occur at too low a frequency and /or intensity or not at all. Examples are language, social behaviors, self-help name a few.

    Areas of normal behavior: Behaviors that occur at a similar rate and intensity in typical children of the same age. An example is gross motor skills. Infrequently, children with autism exhibit special areas of skill such as memory or mathematical or artistic skills.

  • Functional analysis

    Functional analysis helps the treatment provider find the meaning of the child's behavior for that child. Once the meaning of the behavior is found, a more acceptable behavior (functional equivalent) can be taught to serve the same purpose.

    The function of the behavior may vary depending on the situation in which it occurs.


    • Screaming in the toy store ----> "I want a toy"
    • Screaming in school ------> "This work is too hard right now"
    • Self-injury ------> "I want to be left alone" or "I want a break" or "Keep telling me not to do this, I like the attention"
    • Aggression to a peer while playing ------> "I want a turn"
  • Steps in a Functional Analysis:
  1. Find the function of the behavior
    1. Define the behavior
      • What, where, who, when, How intense, what does it look?
      • Your description should allow someone not familiar with the behavior to readily identify it
    2. Obtain history of the behavior
      • When was the onset?
      • Has it happened before, under what circumstances?
      • Does it or has it corresponded to certain times of year, events, etc?
    3. Analyze antecedents and consequences
      • Circumstances that precede the behavior: Where, w/whom, what activity (scatterplot)
      • Circurnstances that follow the behavior
    4. Environmental analysis
      • Is the learning situation appropriate (developmentally, cognitively, functionally)?
      • Is the child healthy
    5. Meaning of the behavior
      • From the data you collect, what can you conclude about the meaning of the behavior for that person? Communicative, stress release, attempt at socializing?? 
  2. Find an acceptable functional equivalent of the problem behavior

    A Functional Equivalent of a problem behavior is an alternative, acceptable behavior that serves the same purpose for the child.

    Example: Tommy hits his teacher sometimes when she sits next to him at his desk during a color sorting drill. Ms teacher reacts by explaining to Tommy why he shouldn't hit and putting him into time-out. When he comes back she gives him another activity to do.

    1. Problem behavior:
    2. Antecedent:
    3. Consequence:
    4. Functional Equivalent to problem behavior:
  3. Changing the Behavior
    1. Teach the functional equivalent (appropriate skill) to replace the problem behavior
      • Once the functional equivalent is found, it needs to be taught using basic behavioral principles.
      • Skills to be taught may include: Communication (verbal, non-verbal), self-help skills, play skills, academic skills underlying more complex skills
    2. Change the antecedents of the problem behavior
      • If the child's problem behavior functions to avoid a situation change the antecedents. Ask yourself the following?
        • Is the task too difficult?
        • Is the environment overstimulating?
        • Is the environment understimulating (boring)?
        • Does the child require more structure in his/her activities?
    3. Change the consequences of the problem behavior

      If a problem behavior has developed, it has been rewarded in the past. To decrease a problem behavior, the consequences must be changed.


  • Communication
  • Self-help skills
  • Self-management
  • Environmental Adjustment
  • Play
  • Language
  • Play
  • Perspective Taking
  • Language
  • Specific skill chains
  • Self management
  • Language
  • Fine Motor
  • Pre-Academic skills
  • Short term goals are the many small steps that are combined to make up intermediate goals.
  • For example: short term goals for development of language may include functional use of specific sounds, words or guestures.
  • Short term goals can be effectively taught using Behavioral methods such as Discrete Trial, PRT, or Structured Teaching.


Concepts for Individualized Programming. Behavioral "Tool Chest"

The population of persons with Autism is heterogeneous, each having some similar characteristics but so divergent that individual programming is essential. There are a myriad of different treatments for autism. Some are comprehensive programs and some address only specific areas of the disorder. Treatments not considered to be behavioral include Biological treatments (e.g. naltrexone, Fenfleuramine, nutritional supplements, etc.), Sensory integration therapy, Facilitated communication, Psychoanalytically influenced treatments (e.g. holding therapy, play therapy, etc.) and Auditory integration training. Behavioral treatments (those incorporating ABA principles) have to this date shown the most promise experimentally. Numerous studies are now showing neurological correlates to Autism suggesting future success in treating autism biologically. The other treatments mentioned have had mixed results and few if any conclusive, valid studies have been performed on them. Ideas to Keep in Mind

  1. There is no cure for Autism-yet
  2. There is no single correct approach for all children-yet
  3. It appears that high functioning children can sometimes attain near "normal" functioning in some areas.
  4. There are many variables that determine the success of a program
  5. Unlike children with Down's or other developmental disabilities, these children look "normal". This may be one factor that encourages parents to unlock "the normal child within" and to be vulnerable to those who advertise "cures".

A Review of Popular Programs

  • ABA - Discrete Trial
  • ABA - Pivotal Response Training (PRT)
  • ABA - Sundberg/Partington
  • Structured Learning (TEACCH)

The above programs have been implemented with large numbers of children and have been empirically validated as effective, although different studies report different success rates. These programs each place emphasis on different areas of intervention. Discrete trial methods are effective to teach novel responses, discriminations, chains of responses to form new skills and some academic skills. Naturalistic strategies such as PRT are most effective for teaching emerging skills, spontaneous responses, for fostering generalization and for developing functional/social use of skills. Programs that emphasize environmental structure such as TEACCH are most effective for teaching functional routines, fostering generalization and providing structure and predictability in the child's daily routine.

None of these programs alone provide a complete intervention. Using the 3 approaches together in some form may be the most optimal programming for children with Autism. A possible combination is to rely primarily on naturalistic strategies within a structured environment using discrete trial methods to hasten acquisition of certain skills.

Discrete Trial

  • Examples of programs that follow a discrete trial format
    • The UCLA Young Autism Project/Replication Sights
    • Princeton Child Development Institute (PCDI)
  • Targets/Goals for Intervention

    In general, the program curriculum is adapted from Teaching Developmentally disabled children: The ME Book (Lovaas, 198 1). Categories include Learning Readiness/Attending skills, Non-verbal/Verbal Imitation, Receptive/Expressive Language, Self-help skills, Academic skills and Social skills all from beginning to advanced levels.

    Short-term targets for intervention include mastery of the comprehensive curriculum. Long-term goals are improvements in global (cognitive) measures and freedom from visible signs of autism and integration independently into a classroom setting with typical peers.

  • Major Components
    1. Behavioral and Cognitive assessment
    2. Objective measurement of observable behavior
    3. Early (before 5 years) Treatment
    4. Intensive 20-40 Hours/week Therapy
    5. Possible use of aversives
    6. Curriculum consists of a fist of Target Behaviors from beginning to advanced competency.
    7. Data are kept on all programs of intervention.
  • Teaching Format
    • Stimulus presentation ==> Response ==> Consequence presentation
      (Therapist/Teacher) (Child) (Therapist/Teacher)
    • Stimulus presentation (instruction) should be clear; Child must be attending; During acquisition, instruction is the same each time it is presented.
    • Response is either correct, incorrect or nonexistent and is recorded as such.
    • Consequences vary according to child response. Correct responses receive a reward (verbal + tangible), incorrect and no response receive either a prompt (prompts vary according to the individual program and could include anything from light verbal or physical guidance to repeat presentation of instruction. Prompts are faded as the response becomes more reliable), or verbal reprimand. Consequences must be immediate and contingent on the response.
    • Sessions are generally therapist directed (therapist chooses activity, materials).
    • Sessions vary in length depending on what the child will tolerate. Generally, session length increases as the child gains competence and as motivation increases.
    • As new behaviors are learned, acquisition items are added to the curriculum.

Pivotal Response Training (PRT)

Pivotal Response Training (PRT) ( is another behavioral program that like Discrete Trial utilizes empirically validated methods based on the Principles of Learning. It incorporates the Stimulus ----->Response ~> Consequence paradigm that unlike Discrete Trial emphasizes Child directed activities, Reinforcement of goal directed attempts as well as correct responses, Turn taking, and Direct reinforcement. Because it is easily adapted to any environment at any time PRT is an ideal strategy to be implemented by parents, siblings and peers. PRT shares some ideas of Incidental Teaching (A teaching strategy that relies on naturally occurring opportunities in the environment to promote learning) although it is more structured. Older references to the language component of PRT are labeled Natural Language Paradigm.

  • Other programs that emphasize naturalistic teaching strategies
    • Milieu Training (Hart & Rogers-Warren, 1978)
    • Programs that offer use of Incidental Teaching strategies
  • Targets/ goals for intervention
    • To improve specific skills such as language, play, social skills and self-help skills through increasing motivation, responsivity to multiple cues and self-management.
    • To increase generalization and maintenance of skills
    • To improve global measures of functioning ( language, cognitive, social)
    • No Target Behaviors* (* except in self-management component)
  • Major components
    • Behavioral and Cognitive assessment
    • Objective measurement of observable behavior
    • Parent/peers training
    • Language/play training
    • Self-management (for some children)
    • Data are recorded Pre, Post and Follow-up. No daily data sheets* (*data can be kept on individual behaviors if desired)
    • Specifics of the procedure:
      1. Child attention;
      2. Maintenance tasks;
      3. Shared Control;
      4. Responsivity to Multiple Cues;
      5. Contingent Reinforcement;
      6. Reinforce Attempts and
      7. Direct response-reinforcer relationship.
  • Teaching format
    • Same as discrete trial with some key differences (see below)
  • Basic Principles of PRT

    Adapted from How To Teach Pivotal Behaviors to Children With Autism: A Training Manual. (1989). By: Robert L. Koegel, Laura Schreibman, Amy Good, Laurie Cerniglia, Clodagh Murphy and Lynn Kern Koegel.

    1. Antecedent Components
      1. Child Attention
        • Instruction/opportunity to respond must be clear, appropriate to the task, uninterrupted, child must attend.
      2. Maintenance Tasks
        • It is important to intersperse maintenance tasks (tasks the child has already learned) with acquisition tasks. The proportion should be about 50% each.
        • Increases motivation, decreases frustration
      3. Shared Control
        • Child's choice (within reason), increases motivation.
        • Shared control includes turn-taking. This interaction allows the therapist to provide multiple examples of appropriate language and play.
      4. Responsivity to Multiple Cues
        • Demand of child response to 2 or more components within the environment (e.g." find your blue pants").
    2. Consequence Components
      1. Contingent
        • Immediate therapist response - therapist response should be appropriate to and dependent upon the child's response.
      2. Reinforce Attempts
        • Any goal directed attempt should be reinforced. -significantly decreases frustration
      3. Direct Response- Reinforcer Relationship
        • The reinforcer should be a natural consequence to the desired behavior. -this is more natural and increases understanding of language and motivation to use it.


Structured Teaching (e.g. TEACCH: Schopler, Mesibov & Baker, 1982)

Teacch is a program whose principles have been implemented for over 20 years. It is wen adapted to classroom use as it promotes independence in students. TEACCH is designed to improve environmental adaptation. This is accomplished through structured teaching by a) modifying the environment to accommodate the child with autism's individual needs and b) by teaching specific skills

The 4 components of structured teaching are:

  1. Attention to Physical Structure
    • Room layout
    • Developmental considerations
    • Individualization of work areas
    • Providing a transition area
  2. Schedules
    • Attention to language ability
  3. Work Systems
    • Developmental considerations
    • Attention to individual needs
  4. Task Organization
    • Individualization
    • "jigs"