Beyond Words: How PECS Helps Autistic Children Communicate

If you have ever spent time exploring the world of Applied Behavior Analysis, you have likely come across some pretty technical-sounding terms. One of the most critical concepts for understanding why we do what we do is the "Motivating Operation," or MO. Within that concept, we find a fascinating phenomenon: the behavior-altering effect. In this article, we are going to dive deep into the mechanics of motivation. We will answer the question, " What is a behavior-altering effect in ABA ?" and explain how it influences the daily lives of children with autism and ADHD. Understanding this concept is like finding the "remote control" for behavior—it explains why a child might work hard for a cracker one minute and ignore it the next. The Core Concept: Defining the Behavior Altering Effect To understand what a behavior-altering effect is in ABA , we first have to look at the broader umbrella of Motivating Operations (MOs). An MO is an environmental variable that does two things: It changes the value of a consequence (Value Altering Effect). It changes the current frequency of all behavior that has been reinforced by that consequence in the past ( Behavior Altering Effect ). While the "value-altering effect" tells us how much a child wants something, the behavior-altering effect describes the actual change in their actions. It is the "right now" impact on behavior. The Two Sides of the Coin: Evocation and Abatement The behavior-altering effect generally manifests in two ways: Evocative Effect: An increase in the current frequency of behavior. For example, if you haven't eaten all day, your "food-seeking" behavior is evoked. You start looking in the pantry, checking fridge apps, or asking others for a snack. Abative Effect: A decrease in the current frequency of behavior. If you just finished a five-course Thanksgiving dinner, your "food-seeking" behavior is abated. You aren't going to get up to find a snack because the motivation isn't there. How It Works: The Science of Antecedents In the ABCs of ABA (Antecedent-Behavior-Consequence), the behavior-altering effect happens at the Antecedent stage. It is important to distinguish this from reinforcement. Reinforcement changes how a child behaves in the future, but a behavior-altering effect changes how they behave immediately. Why Does It Matter for Autism and ADHD? For parents of an autistic child or a child with ADHD , recognizing what a behavior-altering effect in ABA is can prevent a lot of frustration . For Autism: Many children with autism have specific sensory needs. If a child is sensory-deprived, the behavior-altering effect might evoke "stimming" or movement-seeking behaviors. For ADHD: A child with ADHD may experience a high evocative effect for novelty. When a task becomes "boring," the behavior-altering effect of that boredom may evoke off-task behaviors or looking for distractions. Establishing Operations (EO) vs. Abolishing Operations (AO) To fully grasp what a behavior-altering effect is in ABA , we must look at the two types of Motivating Operations that trigger these effects. 1. Establishing Operations (EO) An EO is a condition of deprivation . When a child has been without a preferred toy, social interaction, or a specific food, the value of that item goes up. The Value Altering Effect: The toy becomes highly "valuable." The Behavior Altering Effect: This evokes behavior. The child is more likely to use their communication device, ask politely, or (if they lack those skills) engage in challenging behavior to get that toy. 2. Abolishing Operations (AO) An AO is a condition of satiation . If a child has been playing with their iPad for three hours, the value of the iPad goes down. The Value Altering Effect: The iPad is no longer a strong reinforcer. The Behavior Altering Effect: This abates behavior. The child is less likely to follow instructions that are reinforced by iPad time because they’ve had enough. Behavior Altering Effects in Daily Life: Real-World Examples To truly understand what a behavior-altering effect is in ABA , it helps to see it in action. Let’s look at three common scenarios: Scenario A: The Water Bottle Imagine a child playing outside on a hot day. The MO (Deprivation): The child hasn't had water in two hours and is sweating. The Behavior Altering Effect: This evokes behavior. The child immediately walks to the kitchen, points to the fridge, or says "water." The heat has evoked the behavior of seeking hydration. Scenario B: Social Interaction Consider a child who has been at school all day in a quiet, structured classroom. The MO (Deprivation): The child has had very little one-on-one attention or physical play. The Behavior Altering Effect: Upon coming home, this evokes behaviors like jumping, shouting, or tugging at a parent's sleeve. The lack of social/physical input has evoked high-energy social-seeking behavior. Scenario C: Sensory Overload A child is in a grocery store with bright fluorescent lights and loud announcements. The MO (Satiation/Aversive Stimulus): The child has had "too much" noise. The Behavior Altering Effect: This evokes "escape" behaviors. The child might cover their ears, sit on the floor, or try to run toward the exit. In this case, the noise evokes any behavior that has successfully ended the noise in the past. Capturing and Contriving Motivation Capturing Motivation: Our therapists wait for a natural EO to occur. If a child naturally wants to go outside, we use that evocative effect to teach them how to ask for the door to be opened. Contriving Motivation: We might create an EO. For example, if we want to work on the word "open," we might put a favorite toy in a clear, locked container. This creates deprivation, which has a behavior-altering effect that evokes the child’s communication skills. Reducing Challenging Behavior Often, what parents perceive as "bad behavior" is actually just a behavior-altering effect in response to an environment. By changing the environment (the MO), we can abate challenging behaviors before they even start. If we know a child is tired (an EO for escape), we might reduce the difficulty of their tasks to prevent a meltdown. Deep Dive: Unconditioned vs. Conditioned Motivating Operations To provide a comprehensive answer to what a behavior-altering effect is in ABA , we must distinguish between biological needs and learned needs. Unconditioned Motivating Operations (UMOs) These are biological. We are born with these. They include: Food and water deprivation. Sleep deprivation. Oxygen deprivation. Temperature changes. Pain. Any of these will have an immediate behavior-altering effect . If you are in pain, it will evoke behaviors that lead to pain relief (like taking medicine or rubbing a sore muscle). Conditioned Motivating Operations (CMOs) These are learned. For example, the "value" of a key only exists if you are facing a locked door. The Locked Door (CMO): Creates a need for the key. The Behavior Altering Effect: This evokes the behavior of searching your pockets or calling for help. Conclusion: Partner with Inclusive ABA Understanding the science of motivation is the first step in supporting your child’s growth. When we understand what a behavior-altering effect is in ABA, we stop seeing behaviors as "random" and start seeing them as functional responses to the world. At Inclusive ABA , our clinical team is expert at identifying these subtle shifts in motivation. We use this science to create a supportive, "just right" learning environment where your child feels motivated, understood, and successful. Whether your child has autism or ADHD , we are here to provide the specialized care they deserve. Ready to see the difference that science-based, compassionate ABA can make? Call Inclusive ABA today to schedule a visit or a consultation. Let’s work together to unlock your child’s full potential. Frequently Asked Questions