This cluster shows how to teach a child to ask nicely instead of hitting or screaming. It explains why we must stop giving treats for problem acts while we reward the new words or signs. Then it tells how to slowly give fewer treats without the bad stuff coming back. BCBAs like this because it keeps therapy working when mom or teacher can’t give a cookie every single time.
Functional communication training (FCT) teaches a person to request what they need using words, signs, or a device, instead of using problem behavior. It is one of the most well-supported interventions in ABA. Research shows it produces large reductions in challenging behavior for young children with autism, with even stronger results in school settings than at home.
FCT works best when you pair it with extinction — stopping all reinforcement for the problem behavior while delivering it reliably for the new communication response. But extinction is not always safe or acceptable. When you cannot use it, focus on reinforcer quality for the communication response. Making the new request clearly better than the problem behavior is the most powerful way to shift behavior without extinction.
Schedule thinning is the step most likely to cause treatment to fall apart. After FCT reduces problem behavior, you need to gradually shift from rewarding every request to rewarding some requests, then fewer. Research from 2024 updated the field's guidance: using a fixed-lean approach — jumping to the target schedule — is often faster than gradual thinning, and multiple-schedule cues help the learner tell when reinforcement is available.
Chained schedules work better than tandem schedules when thinning FCT reinforcement. Adding extinction and delay or denial tolerance training produces the biggest behavior reductions. For learners who become prompt-dependent, a package of vocal prompt fading, longer response windows, and constant time delay can eliminate that dependency without increasing problem behavior.
Common questions from BCBAs and RBTs
Functional communication training teaches a person to use words, signs, or a device to request what they need, replacing problem behavior that serves the same function.
Use a fixed-lean approach — start with the target schedule rather than adding many small steps. Use multiple-schedule cues to signal when reinforcement is available. Plan for some increase in problem behavior and have a clear decision rule for when to back up.
Focus on reinforcer quality for the communication response. Research shows that making the FCT reinforcer clearly better than the problem behavior's reinforcer — in quality, not just size — is the most effective lever when extinction is not an option.
FCT works best when problem behavior has a clear, single function. If escape is just one of several functions, results are less consistent. A thorough functional analysis before treatment helps you identify how many functions to address and how to adapt the FCT plan.
Use a package of vocal prompt fading, longer response windows before prompting, and a constant time delay. Research shows this package can eliminate prompt dependency without increasing problem behavior.