That was the thing that killed the dinosaurs, right? This might be true for some but not for a Behavior Analyst.
Basically, it means a bad behavior "gets worse" before it gets better. This may sound counterintuitive but it's scientific fact. Once a behavior is learned, it can be really hard to unlearn it. If I was able to get my favorite video via tantrums in the past then I'm going to keep trying until I get what I want or I will eventually give up and try something else. Typically, someone will push harder, thinking that the reward might just require a little more effort this time. Hence, the behavior gets worse, temporarily.
Once you've passed the difficult point, the behavior will start to decline. The biggest struggle is holding out until after this point. No one likes listening to their child yell, scream, etc, but it will abate. The storm will clear, and your child (or anyone else that you're working with) will stop once they realize that this behavior doesn't get them what they want. This can take a while but it's worth it in the end.
Don't stop part way through!!! If you do, you've just taught them that they have to up the ante in order to get what they want. In the future then, the behavior will be so much worse than it was before!
Enduring the extinction burst can be hard, but worth it it the long run and hopefully your kids are easier to manage than dinosaurs.
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