Lesson 3 ABA Terms and Definitions


Lesson 3 consists of a brief breakdown in the ABC's of behavior or antecedents, behaviors/responses and consequences.  This is the basic "unit" of learning.  Basically, you must be clear on the behavior you want to teach, the stimuli you will use to teach it and the reinforcer you will use to increase the liklihood of that behavior happening again in the future.  MO is critical...If you have no MO, you have no reinforcer.  If you have no reinforcer, you aren't teaching.

Antecedent - Motivaional Operation

Motivational Operation (MO)/Establishing Operation (EO):

a)Temporarily increases the effectiveness or value of a reinforcer.

b)Temporarily increases the behaviors that have been consequated by that reinforcer in the past.

Satiation and Deprivation

Things that affect an EO:

1) Deprivation – (Increases value). When you haven’t had the desired item for a while. Ex: When you’ve been on a diet, pizza becomes highly desirable.

2) Satiation – (Decreases value). When you’ve had a great deal of the desired item recently. Ex: If you eat pizza for lunch every day, you might not want it any more.

3) Competing EO – (Decreases value). The value of some other behavior is stronger. Ex: The child really wanted to play with that toy but you asked so many questions that the value of escaping became stronger than the value of the toy.


1. If you’re low on cash, it temporarily increases the value of extra money and results in the types of behaviors that have allowed you access to money in the past (extra job?, extra work to earn a bonus?)

2. If a child has a favorite toy that he hasn’t played with for a long time, the value of that toy is temporarily increased and results in an increase the types of behaviors (talking?, Screaming?) that have gotten them the toy in the past.

3. If a child is in a loud, noisy environment that he finds uncomfortable, it temporarily increases the value of escaping and results in the types of behaviors (hitting?, biting?, screaming? Saying, "Let’s go”) that have resulted in escaping in the past.


Response/Behavior: An observable or measurable event. Some behaviors or responses can only be observed and measured by the person experiencing the event. Examples of behaviors might include: Thinking about eating pizza. Asking for pizza. Opening the pizza box. Telling someone the pizza is here. eating the pizza. (each of these behaviors will have different antecedents and consequences.

Antecedents /Stimuli- Neutral, Discriminative and S-Delta

Stimulus - Anything that a person can experience through their senses, anything that can be seen, heard, smelled, felt, or tasted. Different people can experience the same sensation in different ways. A stimulus that one person might experience as pleasurable another may experience as painful or aversive.

Neutral- Some stimuli cause neither pain nor pleasure and have not been associated with anything else

Sd-stimulus can become associated with another event when it is followed by either reinforcement or punishment. Then it is considered a discriminative stimulus (Sd). In other words, when that stimulus is present, it indicates the availability or possibility of reinforcement or punishment.

S-Delta-a stimulus is associated with the unavailability of reinforcement, it is called an S-Delta condition.


Neutral Stimulus - Daddy says, “touch the dog” and this is the first time the child has ever heard this phrase. The child hears the words but they are not associated with anything either positive or negative.

Discriminative Stimulus - A child is sitting on his father’s lap and looking at a book. Daddy says, “Find the dog” and takes the child’s hand, guiding (prompting) him to touch the dog. When the child touches the dog, daddy hugs him and says “That’s right!” The child finds this quite pleasurable (reinforcing) so when daddy turns the page and says “Find the dog” again, the child again touches the dog, not waiting for his daddy to guide him. Because the behavior of touching the dog has been followed by reinforcement in the past, hearing “Find the dog” when the dog is present suggests the possibility of reinforcement if he touches the dog again.

S- Delta - To continue the example above, if the child touched the “cat” instead, daddy does not give him a hug and say, “That’s right!” The behavior of touching the cat is associated with the unavailability of reinforcement whenever he hears “Find the dog”.

Consequences- Reinforcement and Punishment

Consequences- Reinforcement and Punishment Reinforcement:

a) Something that happens after a behavior occurs that increases the likelihood of occurrence of the same behavior under the same conditions in the future.

1. Positive Reinforcement - Giving something the person finds desirable (reinforcer) after the behavior occurs and increases the occurrence of the same behavior under the same conditions in the future. Examples:

a) A child wants a cookie and continues screaming as parents search for what he wants. The next time the child wants a cookie, he is more likely to scream to get it.

b) A child wants to play with a ball so he signs “ball”. The parent gives him the ball so the next time he wants the ball, he signs “ball” again.

2. Negative Reinforcement - Removing something the individual finds aversive that increases the occurrence of the same behavior in the future.


a) A child finds his brothers presence annoying. He bites the brother. His mother comes and takes the brother away. This increases the likelihood that he will bite his brother the next time he wants to get rid of him.

 b) A child finds “circle time” at school aversive and starts screaming. The teacher puts him in “time out”. This increases the likelihood that the next time he wants to leave circle he will scream again.

Punishment - Applying something the individual finds aversive (positive punishment) or taking away something the individual finds pleasurable (negative punishment) right after the behavior has occurred that reduces the liklihood that a behavior will happen again in the future.

Tracy Vail, MS,CCC/SLP  Let's Talk

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