Ratio Strain

Ratio strain is a term used to describe a situation in which the required amount of work, or response, no longer produces the desired behaviors that were previously produced by lower requirements. Let’s look at a ratio strain example. You give your daughter $5 for cleaning her room. She does a great job of organizing […]

What is Autism?

Heartbreak and Help. No parent is fully prepared for the diagnosis of Autism. Some react with denial, others with fear. Most are confused. “What is Autism?” “Is there a cure?” “ What will our lives be like?” “Why my child?” Let’s start at the beginning. What is Autism? Autism Spectrum Behavior (ASD) is a disorder […]

Variable Ratio

Used in teaching and proper use of reinforcers, the variable ratio is a way of describing a group of different response-based schedules of reinforcement. For example, the learner’s correct 2nd, then 3rd, then 6th, then 1st responses will be reinforced.  These different response rates (2nd, 3rd, 6th, and 1st) will be labeled as VR-3—the average […]


Used in teaching and proper use of reinforcers, variable interval is a way of describing a group of different time-based schedules of reinforcement. For example, the child’s first correct response will be reinforced after 5 minutes, then after 3 minutes, then after 4 minutes. These different intervals (5 minutes, 3 minutes, and 4 minutes) will […]

Verbal vs Non-Verbal

These are very loose terms used by individuals to describe a person that can vocally communicate (“verbal”) and a person that cannot (“non-verbal”).    

VB-MAPP Assessment

Stands for Verbal Behavior Milestones Assessment and Placement Program. An assessment and curriculum tool created by Dr. Sundberg. This tool focuses on verbal assessment to get a complete snapshot of verbal abilities, strengths, and deficits. Domains include manding, intraverbals, echoics, etc.

Triennial IEP

Also called triennial assessment or triennial review.   Students who receive special education services must be re-evaluated comprehensively to determine their eligibility for continued special education services three years after the initial eligibility.


May refer to changes from one activity or setting to another such as from an early childhood program to school or from a preferred play activity to a work activity. Transitions are typically very difficult for individuals with ASD, particularly unplanned or surprise transitions.

Token Economy

This is a system of reinforcement in which a learner “earns” conditioned reinforcers such as coins, tickets, or plastic chips to name a few examples immediately after performing a desired behavior. These tokens can be then used to “buy” something that the learner truly wants.


Also called time-out from reinforcers. As the label suggests, this is a consequence in which a person loses some or all opportunities to gain access to reinforcers.  A good way to implement this procedure is removing the person from an area where reinforcement is available (e.g., playground or the living room where the game console […]

Task reduction

Decreasing the demands put upon the learner in an effort to avoid or decrease frustration levels which then facilitates overall task completion.

Task Analysis

This is the process of breaking up a skill or a behavior into smaller, teachable steps.  For example, brushing teeth as a behavior may be broken down into, say, 7 clear steps that can be taught: get toothbrush, squeeze toothpaste on the brush, brush left side teeth, brush center teeth, brush right teeth, rinse mouth, […]

Target Behavior

This is the behavior of interest designated to be increased or decreased.  


A tact is the name or description of an item that is present in the speaker’s environment. For example, a commercial airplane is flying overhead while you and your son are out in the park.  Your son looks up and says, “airplane.”

Sensory Integration

Sensory integration refers to different strategies or techniques used to meet, raise, or lower internal sensory needs such as weighted vests, sensory diets, or brushing procedures. Often an OT will recommend sensory integration via a sensory diet. Sensory integration is not empirically supported for its effectiveness.

Stereotypic/Repetitive behaviors

Loosely referred to as “stims.” These “stereotypies” are self-initiated, highly repetitive movements that can be vocal or motor in nature.  Determining the function(s) is important if the goal is to place the behavior under management.

Specific Praise

Also called “labeled praise.” Instead of just saying “Good job!” when a learner just wrote his name much better than the last time he wrote it, say “I like the way you wrote your name today.”  This technique is a good way to clearly inform the learner the exact behavior that you are teaching him.


This is an ABA-based teaching technique in which “successive approximations” toward the target behavior being taught are reinforced until the learner can perform the behavior successfully. For example, an instructor reinforces the way a student writes the letter “A” each time he writes it better than the last time he wrote it.

Self-injurious behavior (SIB)

These are behavior that a person performs that result in physical injury to the body. Self-injurious behaviors can be: hitting oneself with hands or other body parts, banging one’s head unto the corner of a table, biting one’s hand, or picking at skin or scabs to name a few.  The function(s) of the SIB must […]


A loose term which refers to imitative vocal behaviors.  For example, a young child reciting an entire radio commercial or a few lines from a movie can be a form of scripting.


Term used to describe the weakening effect of a reinfocer on a behavior due to its “over-use.”  It is best to have a selection of reinforcers to use in ABA programs to avoid satiation.


A rule is a verbal description of a behavior contingency in which a learner does not need to experience the consequence of breaking the rule.  For example, the rule “Do not run while you are on the playground structure” is a pretty good rule to follow for a young child so he can avoid the […]

Restitutional Overcorrection

A form of positive punishment in which a learner is required to repair the damage caused by his behavior or return the environment to its original state and then have the learner perform extra actions to make the environment “better” than it was prior the misbehavior. For example, after throwing a few chairs in the […]

Response Cost

A form of negative punishment in which a person loses some reinforcers after performing an undesired behavior. For example, a student losing points that she can accumulate during the school day after breaking an established classroom rule.

Reinforcer Assessment

This refers to different ways to find out which items or activities can be used as reinforcers for a specific learner.


A reinforcer is something—anything—that is used during or after a behavior that leads to the strengthening of the behavior it followed over time  


Put simply, this is an “understanding” of something and refers to behaviors that require a non-vocal action or motor response.


Registered Behavior Technician. For direct level staff, this is a credential that denotes the person has met specific educational and experience standards in addition to passing an examination. A RBT works only under the supervision of a BCaBA or a BCBA. Currently, it is not a required credential for direct level staff to possess; however, […]


Stands for Questions About Behavior Function.  This is a 25-item, indirect assessment tool co-developed by John Matson and is used to assess the function of a target behavior.  The QABF can be easily administered and assesses for the following functions: attention, escape, physical, tangible, and non-social.


Punishers (or punitive stimuli) can be anything. In ABA, a punisher must decrease/weaken a behavior by definition. If you hear someone saying something like “Yes, I keep scolding my son but he still continues drawing on the walls with his beloved crayons a lot more now—punishment does not work!”  Given that example, “scolding” is not […]

Prompt Dependent

To begin, a person is never “prompt-dependent.” Prompt dependency is when an individual’s response or behavior has become so reliant on someone else’s assistance over time. The learner then “stops” attempting to do the task independently. This dependency is often produced by the environment’s/instructor’s failure to systematically fade the prompts used during the teaching process. […]


It is an assistance given to help the learner compete a task and there are several types. Physical prompt, gestural prompt, positional prompt, model prompt, vocal prompt, and visual prompt are just a few examples of prompts.

Premack Principle

Put simply, a desired behavior can be used as a reinforcer for a non-/low-desired behavior. For example, spending extra time playing on a gaming console (the highly-desired behavior) can be used as a reinforcer for cleaning up one’s room (the non-/low-desired behavior).  


Speech and Language Pathologist and Occupational Therapist. These are professionals who often work with individuals with autism to provide therapy services related to speech, movement, developmental goals, coordination, and functional communication. Although it may beneficial to include these professionals in your child’s ABA team, using these professionals solely without a BCBA/BCBA-D in the team is […]

Positive Reinforcement

A procedure in which a behavior is followed by an event/item/activity that results in the strengthening of the behavior over time. By definition, the procedure MUST have the anticipated strengthening effect on the behavior for the intervention be considered as positive reinforcement.  Much like positive punishment in which the “punisher” or punitive stimulus can be […]

Positive Punishment

A procedure in which a behavior is followed by an event/item/activity that results in the weakening of the behavior over time. By definition, the procedure MUST have the anticipated weakening effect on the behavior for the intervention be considered as positive punishment.  A “punisher” or punitive stimulus can be anything as long as the behavior […]

Positive Practice Overcorrection

A form of positive punishment in which a learner, after a misbehavior, performs the “correct form” of the behavior, OR a behavior incompatible with the misbehavior for a few times.  For example, a student will simply stand up and walk out of the classroom when he needs to use the restroom. For this procedure, the […]

Planned Ignoring

This is an extinction-based technique used to reduce specific attention-seeking/attention-based problematic behaviors. When implementing planned ignoring, the instructor must be prepared for extinction bursts or “worsening of the attention-based problematic behavior” before the initial problem behavior stops. Again, it is important to remember that planned ignoring is only for challenging behaviors that function for attention.

Picture Exchange Communication System (PECS)

For individuals with difficulties vocally communicating their needs to another, PECS is an alternative communication system that uses pictures.  

Perseverative Behavior (Stereotypical Behavior)

Excessively and stereotypically performing a behavior over time.  Not to be confused with self-stimulatory behavior (“stimming”) as not all perseverative behaviors are auto-reinforced.  


Pervasive Developmental Disorder was previously classified as a form of autism. PDD is no longer a separate diagnosis in the most recent DSM V.


Neuro-Typical. This adjective is more politically-correct to use in describing individuals not living with autism. Use this instead of “normal.”

Normal (versus NT)

To make this brief, avoid using the adjective“normal” when describing individuals not living with autism (or any other diagnoses).


Natural Environment Training is an ABA-based training method where teaching occurs within the natural context of the behavior-environment. This type of teaching promotes generalization and maintenance of the learned behavior.

Negative Reinforcement

Negative Reinforcement

Negative Punishment

A procedure in which a behavior is followed by a removal of an item/event/activity that results in the weakening of the behavior over time.  An example can be the use of time-out from the playground when a child does not follow the rule of “no-pushing peers” which results in the child stopping from pushing her/his […]


Placement of inappropriate items in one’s mouth. Not to be confused with Pica.  


Stands for Motivation Assessment Scale.  This is an indirect assessment tool developed by Durand and Crimmins (1988 & 1992) used to assess possible functions of a target behavior.  A relatively easy tool to administer, it assesses for the following functions: sensory, escape, attention, and tangible.

Mental Retardation (MR)

A diagnosis characterized by significantly under-average general intellectual functioning associated with impairments in adaptive behavior. It can be classified as mild, moderate, severe, and profound. Other states/countries may have a different label for MR (e.g., cognitive impairment or intellectual impairment or intellectual disability).


A mand is a behavior that a person performs to indicate to another person what he or she wants. For example, a child “feels” hungry so she tells her father “Can I have a snack, please?”


The extent to which the learned behavior is able thrive in the absence of the intervention that developed it.


Main-streaming a student suggests that the student will be placed in the least-restrictive neuro-typical classroom (general education classroom) as opposed to a type of more-restrictive special education classroom or program.  It also suggests that the student’s IEP team members have all agreed that the student has ample skills in his or her repertoire to thrive […]


Least Restrictive Environment.  (cited from This is the requirement in US federal law that students with disabilities receive their education to the maximum extent appropriate, with non-disabled peers and that special education students are not removed from regular classes unless, even with supplemental aids and services, education in regular classes cannot be achieved satisfactorily. […]


Intraverbals are like building-blocks to conversation skills. These can be in the form of question-and-answer format and fill-ins and is basically about “talking” about things that are not physically present.


This is what the team will be doing to address the behavioral excesses or deficits that a learner may have.

Inclusive Classroom

An inclusive classroom is a type of classroom that comprises both student living with special needs and students that are neuro-typical. These classrooms are taught by General Education teachers and may have paraprofessionals in the room to provide support to students with an IEP.  

Incidental Teaching

This is a type of training based in ABA in which a learning opportunity is contrived to teach a new skill. For example, teaching the name of an object by having a learner request for it or asking the learner where her desired items is when teaching propositions.


An Individual Education Plan is the individualized education plan that children, adolescents, or adults have if they are enrolled in a special education program. An IEP is an important legally-binding document—parents/guardians should pay close attention in its development and implementation.


A stimulus produces an atypical severe response—overly sensitive.

HOH Prompting

Is a type of an intrusive prompt wherein an instructor physically/manually guides the learner to perform the target task or behavior.

High Functioning/Low Functioning

These two labels are often and very loosely used by individuals and even among professionals; however, the terms are ambiguous and often offensive. The use of these terms when describing a person should be avoided.

Gross Motor Skills

These are the motor activities that involve large muscle groups like swimming, hopping, clapping et cetera.  


Gluten-free and Casein-free. GFCF diets are not ABA-based nor are they empirically supported to be effective.  


Can the learner perform the behavior with another person? A different place?  A different time? Does the person perform the behavior if you change the instruction a little?   Can he now ask for water in more than just one way? These questions tap into the generalizability of a learned behavior.  In an ABA-based intervention, being […]

Functional Communication Training (FCT)

This is a teaching method based on differential reinforcement in which the learner is taught a way to communicate one’s wants or needs instead of the learner performing a behavior that is not socially-appropriate.  For example, a learner is taught to tap another person’s shoulder instead of screaming to initiate a social interaction/a request.

Forward chaining

A teaching technique in which the learner is prompted/taught the first step in a series of steps with the trainer performing the steps after the step targeted for learning.  Once the learner is able to perform the first step, the learner is then taught the first and second step. This process continues until the learner […]


Floortime is a child-led treatment method that is typically administered in a naturalistic play environment. Floortime is not an ABA-based treatment nor is it an empirically supported method in terms of its effectiveness in treating children living with autism.


Used in teaching and proper use of reinforcers, fixed ratio is a way to describe how many responses a learner must do before a reinforcer is given.  For example, a FR-10 suggests that the learner must do 10 responses first after which the 10th correct response will be reinforced. Behaviors on a FI scheduled show […]


Used in teaching and proper use of reinforcers, fixed interval is a way to describe how much time must pass before a learner’s first correct response will be reinforced.  For example, a FI-15 is a way to label a schedule in which the learner’s first correct response after 15 minutes will be reinforced. Behaviors on […]

Fine Motor Skills

These are the motor activities that require the coordination and movement of the smaller muscles of the body such as those of the hand and fingers.

Functional Behavior Assessment (FBA)

This is an indirect process by which behavioral interventions are created. An FBA is intended to determine the function for a behavior by using observation data, interviews, and questionnaires.

Functional Analysis (FA)

This direct process arranges the antecedents and consequences of a problem behavior in an experimental design to determine their separate effects on the behavior of concern.  Although an FA can be used to look into any challenging behavior, in practice, it may be more practical to use a FBA instead.


Free Appropriate Public Education.  FAPE is an education right of children in the United States that is guaranteed by the Rehabilitation Act of 1973 and the Individuals with Disabilities Education Act of 1975.


A procedure in which assistance or supports used for a behavior to occur are systematically made less as the learner’s behavior become more independent.  Failure to systematically fade prompts produce prompt-dependent behaviors.

Extinction burst

This label is used to describe the increase in intensity or rate of a behavior when the behavior no longer results in the usual reinforcer that maintains it over time.  Using Leo’s example above, an extinction burst when his hitting no longer results in a cookie may be stronger hits, and/or screaming, and/or crying, et […]


Extinction is when the consequence that have maintained the behavior will no longer be presented after or during the challenging behavior.  For example, Leo’s mother is in the kitchen near the cookie jar. Leo wants some cookies so he walks to his mother and hits her shoulder a couple of times.  His mother keeps offering […]


Expressive means speaker behavior and is not just limited to vocal mode of communication.  That is, a person can also use sign language, writing on paper, using pictures, or typing on a keyboard/pc to communicate his needs to others.

Escape Extinction

The behavior that usually “stops” an unwanted event no longer effectively stops that same unwanted event.  For example, a child usually cries when presented with a table-task. In the past, the crying behavior has been negatively reinforced by the removal of the table-task.  In escape extinction, the teacher will not remove the table-task regardless of […]

Escape Contingency

A contingency in which performing a specific behavior stops and ongoing event.  For example, a child dropping unto the floor followed by the child crying stop the event of the child having to enter the classroom. Another example can be a student “ending” a math fluency exercise on the computer after finishing three exercises.


As the label suggests, elopement is wandering off, or running away, or any behavior to that effect. As there can be various motivations for a person to elope, a functional assessment or analysis is needed to develop a sound behavior plan to address this challenging behavior.


Echolalia then is a label used to describe a condition in which a person performs echoics. Displaying echolalia does not mean a person is living with autism nor does all individuals living with autism displays echolalia.


An echoic is the repeated word/phrase/sentence that a person performs after hearing the word/phrase/sentence.  For example, Courtney hears her father saying “Be quiet, Courtney!” Courtney says, “Be quiet Courtney!”


The Diagnostic & Statistical Manual of Mental Disorders is used by mental health professionals to diagnose a person. It is a very comprehensive manual that catalogs known mental conditions, disorders, and syndromes and explains how to diagnose each one. 

Discriminative stimulus (SD)

Think of this as a signal for a learner to perform a specific behavior that will then result in a specific event.  For example, you showed your child a picture of a dog, she says “Dog,” then she gets a big hug and a hi-five from you.

Discrete Trial Training

DTT is an ABA-based method of instruction in which a task is isolated and taught to an individual across multiple contrived opportunities until mastery.  Not all skills can be taught via this teaching method.

Differential Reinforcement

Strengthening a specific behavior while placing all other behaviors in extinction.  For example, calling upon a student with a raised hand is reinforced by the teacher by calling the student’s name and giving that student a chance to say her answer while completely ignoring all other students that blurt out the answer.

Developmentally Delayed (DD)

A young child may be given a diagnosis of DD when he is not meeting developmental milestones such as crawling, sitting up, using a pincer grasp, talking/babbling, et cetera. Early identification is the key.


Deprivation works along the lines of motivation in which the more deprived a person is of something that he likes, the more motivated the person may be to do what is asked of him to do.

Contained Classroom

A contained classroom typically has a smaller teacher-to-student ratio than an inclusive classroom and is taught by a Special Education teacher with the inclusion of at least one trained paraprofessional.


Is a person who develops a treatment/behavioral plans, trains and supervises staff. It is important that a consultant possess a BCBA or a BCBA-D certification along with the pertinent experience required to oversee an ABA program or services.


In “ABC” of behavior, it is the consequence of a behavior OR whatever follows after the occurrence or during the occurrence of a behavior.

Conditioned reinforcers

These types of reinforcers acquired their reinforcing properties only after they are paired with other stronger [unconditioned]reinforcers. For example, a plastic chip by itself may not be reinforcing but it may be so only after the plastic chip is associated with, let’s say, a bag of peanuts (assuming the learner “loves” peanuts).  


Simply put: a person assessed to have at least two diagnoses at the same time.  For example, a person is living with autism and an anxiety disorder.

Chronological Age/ Developmental Age

Chronological age is the actual age calculated by a person’s birthdate. A developmental age is based on level of functioning/cognitive ability, and adaptive skills. For example, a child can have a chronological age of 12; however, an assessment can suggest that her developmental age is of a 4 year-old.  


Used to teach complex skills that comprise of numerous steps. To teach, each step is identified first then taught until mastery. Chaining can be either done by backward, forward, or total task analyses with each type having its pros and cons.

Bio- Medical Approach

This approach to treating Autism is based on addressing possible biological causes of, or issues associated with Autism, such as heavy metals or an over growth of yeast, or some form of inability to process types of foods. These approaches currently lack empirical evidence regarding their effectiveness.

Behavior Contrast

This term is used to describe a situation in which a behavior may occur differently given two different situations.  For example, Cindy bites her nails so badly that her cuticles start to bleed. Her parents are divorced so she spends one month at a time with either parent. Cindy’s mom scolds her every time she […]

Behavior Chain

This is the term used to label the group of steps necessary to perform a complex behavior. For example, if there are eight steps (behaviors) a person must do to brush his or her teeth, then those eight behaviors are “links” that when done together in the correct order, compose the behavior chain to brush […]


A behavior must be observable and/or measurable for it to be considered a behavior.


Individuals with Disabilities Education Act. First passed in 1975, the primary purposes of IDEA are to provide a free and appropriate public education (FAPE) to children with disabilities and to give parents a voice in their child’s education.  


How a behavior is before an intervention to either strengthen or weaken that behavior. Knowing the baseline is very important in any ABA program/behavior plan in order to determine the effectiveness of the intervention.  


This is the opposite of hypersensitivity in which a person has no or little response from a stimulus.


These certifications are awarded to individuals that have received extra training and/or graduate-level coursework, supervised fieldwork, have passed an examination, and have completed requirements to maintain their credentials.

Backward Chaining

A teaching technique in which the learner is taught the last step of a skill first then work back until all steps are done independently. For example, it takes five steps for a child to perform a skill. The instructor will provide the child with maximum support from Step 1 through Step 4 with prompts […]

Avoidance Contingency

If a person sees something that he does not like is about to happen, the person performs a behavior that will result in the unwanted event being delayed or prevented from happening.  For example, a child’s mother placed a bowl of broccoli for a child to eat. As a result, the child runs away from […]

Aversive Stimulus

An aversive stimulus is anything that someone simply does not like. What those things are varies per person at any given time.

Autism Spectrum Disorders

Autism, or autism spectrum disorder (ASD), refers to an assortment of conditions characterized by difficulties with social skills, repetitive behaviors, speech and nonverbal communication, as well as by unique strengths and differences which means individuals living with autism are most likely showing very different symptoms, with symptoms themselves expressed very differently, from each other.

Aspergers Syndrome

Aspergers Syndrome used to be considered separate from ASD. The main differences was that these individuals are very verbal and have normal to high IQs, but have social difficulties/impairments, and may have more neurological issues. These individuals sometimes could go undiagnosed until they were older, since common symptoms of Autism may not be present or […]


In behavior analytic terms, an antecedent is simply what happened right before the behavior.  It is very important to be very specific and accurate as to what the actual antecedent is.

Acquisition Task

A behavior or a skill that is still not part of a person’s behavior repertoire. This behavior is skill is actively taught to a learner until it is learned.

ABC’s of Behavior

Also known as the 3-term contingency it is a simple tool used to determine the function of a behavior. The A is for antecedent (what happens right before the behavior of concern), the B is the actual behavior of concern, and C is the consequence (what typically happens right after or during the occurrence of […]

ABLLS Assessment

This is a comprehensive assessment and curriculum planning tool created by Sundberg & Partington. This tool allows an evaluator to assess across 25 varied domains to get a thorough picture of a child’s functioning level, strengths, and deficits. Domains include self-help skills, gross motor skills, receptive skills, group instruction, etc.

Applied Behavior Analysis Therapist

“ABA Therapist” is just one of the many ways to label professionals working directly with clients or students.  The label we use at the LeafWing Center is Behavior Technician (BT). Other labels used are 1:1s, para-professionals, tutors, behavior therapists, shadows, and behavior interventionists to name a few. The label used depends on the agency/company/school/institution providing […]

Applied Behavior Analysis

A sub-field of psychology that focuses on the implementation of evidence-based interventions or instructions. Numerous ABA-based interventions include, but are not limited to, Discrete Trial Training, Incidental Teaching, Pivotal Response, Training, Functional Communication Training.