What Is Function of Behavior
Function of behavior is the underlying reason your child acts a certain way. It's the "why" behind the behavior. Applied Behavior Analysis (ABA) therapists break this into four main categories: escape, attention, tangible (access to desired items), and sensory stimulation.
Here's what makes this concept practical: a tantrum that looks identical on the surface can have completely different causes. One child screams to avoid a task. Another screams because they want interaction with you. A third screams because they're seeking sensory input like the sound itself. Your response needs to match the actual function, or you'll reinforce exactly what you're trying to stop.
Why It Matters
Identifying function determines whether your intervention works. Studies in ABA show that interventions matched to the actual function of behavior have success rates around 80-90%, while mismatched interventions often make behavior worse. If you punish escape-motivated behavior, the child fights harder to leave the situation. If you ignore attention-seeking behavior when that's the function, the behavior typically intensifies before it improves.
This also explains why your child's behavior changes depending on context. A sensory-seeking toddler who crashes into furniture during quiet time needs a different approach than one who's seeking your reaction. Developmental milestones matter too: a two-year-old's limited language makes attention-seeking behaviors more likely, while a five-year-old with better communication may have shifted to escape or sensory functions.
How to Identify Function
- Escape function: Behavior increases when the child wants to leave a task, place, or transition. Remove demands briefly after the behavior, and you'll see it spike. Example: refusing to get dressed before school.
- Attention function: Behavior increases around you, your voice, or eye contact. Works whether you respond positively or negatively. Example: whining intensifies when you're on your phone.
- Tangible function: Behavior gets the child something they want: a toy, snack, or screen time. Behavior stops when they have the item. Example: screaming until you open the pantry.
- Sensory function: Behavior happens regardless of who's watching or what's available. The behavior itself feels good to your child. Example: hand flapping, spinning, jumping on the couch repeatedly.
Sensory Processing and Function
Children with sensory processing differences often have behaviors driven by sensory function. A child who's under-responsive to sensory input might crash, jump intensely, or seek deep pressure because their nervous system isn't getting enough signal. A child who's over-responsive might cover their ears, avoid certain textures, or escape situations with unexpected sounds. Recognizing this as a function means you provide sensory outlets rather than punish the behavior.
Common Questions
- Can a behavior have multiple functions? Yes. A child might scream during a task both to escape the task AND to get your attention. With ABA assessment, the therapist identifies which function is strongest, then addresses that first.
- How long does it take to figure out the function? A behavioral therapist typically collects data over 3-5 days to a week. As a parent, you can spot patterns in under two weeks by noting when the behavior happens, what happens right before it, and what happens right after.
- What if I get the function wrong? You'll notice your strategy isn't working. If you think it's attention-seeking and ignore it, but it's actually escape-driven, the behavior will get worse or switch to a different behavior. That's your cue to reassess with a professional.
Related Concepts
Understanding function of behavior connects directly to these key concepts: