Why Most People Get Desensitization Wrong

I talked to a lot of people over the holidays, and—inevitably—dog stuff came up here and there. I do my best not to talk dog training outside of work, but I couldn’t help taking some mental notes. One thing stood out: almost nobody understands what desensitization actually means. Most people are working with a definition that’s not only inaccurate, it can actually be harmful. At the very least, it’s not going to be effective.

The common understanding goes something like this: expose your dog to the thing that bothers them until they get used to it and stop reacting. Just keep putting them in the situation—whether that’s seeing other dogs, being left alone, hearing loud noises—and eventually they’ll realize it’s not a big deal. The more exposure, the better. They’ll adapt. But this interpretation misses the most critical part of desensitization: the intensity level matters more than anything else. When you expose your dog at a level that’s too intense—past the point where they can stay calm and actually learn—you’re not doing desensitization at all. You’re gambling on whether your dog will habituate (seem to get over it) or sensitize (get worse). And that gamble doesn’t usually pay off the way people hope.

Desensitization is the gradual, systematic exposure to a trigger at a low enough intensity that the dog remains calm and can actually learn. The key is starting well below the dog’s threshold—the point where they’d start to show stress or reactivity. For a reactive dog, this might mean seeing another dog at 100 feet away instead of 20 feet. For a dog with separation anxiety, it might mean you step just outside the door for 3 seconds instead of leaving for an hour. For a sound-sensitive dog, it might mean playing thunder sounds at barely audible volume rather than full blast. The dog notices the trigger, but stays relaxed—maybe glances at it, then looks back at you or goes back to what they were doing. Over time, you very slowly increase the intensity or duration, always keeping the dog in that calm, learning state. This is where real emotional change happens.

When you expose your dog at that ineffective middle level—beyond desensitization but not quite flooding—you’re gambling on one of two outcomes: habituation or sensitization. Think about moving to a new apartment next to a BART train. Every day the train goes by. Over time, one of two things happens: either you habituate (you stop noticing the sound, it fades into the background), or you sensitize (you become more and more aware of it, more annoyed by it, until eventually you’re looking for a new place to live). The same principle applies to your dog and their triggers.

Habituation means your dog genuinely gets used to the trigger—they stop reacting because they’ve learned it’s not a threat. Just like you might stop hearing the BART train after a few months, your dog might stop reacting to the mail carrier, dogs on walks, or being left alone for short periods. While habituation can work, it requires your dog to endure repeated stress. Desensitization achieves the same outcome—a dog who’s comfortable with the trigger—but does so by keeping stress low throughout the process. Why put your dog through more distress than necessary?

But here’s the real risk of working in this middle zone: sensitization. Instead of getting used to the trigger, your dog becomes more reactive to it over time. Like becoming increasingly bothered by that train until you can’t stand it anymore, your dog’s fear or reactivity intensifies with each exposure. Their threshold lowers—a dog who used to react to other dogs at 20 feet now reacts at 50 feet. A dog who could handle 30 seconds alone now panics at 10 seconds. A dog who was only nervous during thunderstorms now gets anxious when they see clouds. This is why working beyond desensitization levels is so risky: you might get lucky and your dog habituates, but you might make things significantly worse.

Flooding is full submersion in the trigger with no escape—the dog is way over threshold, often in a state of panic or extreme stress. Think: throwing a dog who’s afraid of water into a pool, forcing a fearful dog to be petted by strangers, or leaving a dog with separation anxiety alone for hours on their first day home. The dog can’t get away, can’t make it stop, and is completely overwhelmed. Flooding is a gamble with high stakes: sometimes the dog’s behavior suppresses (they shut down or stop reacting because they’ve learned that nothing they do matters), and sometimes they sensitize severely, developing even more intense fear or anxiety. Modern dog training avoids flooding because there are much more effective and humane alternatives—like desensitization—that actually change how your dog feels rather than just shutting them down.

Here’s how to think about these zones on a practical 1-10 scale:

1-3: Desensitization zone – The dog notices the trigger but remains calm and relaxed. They can take treats, respond to cues, and their body language is soft. This is where real learning and emotional change happen.

4-6: The risky middle – The dog is noticeably stressed—maybe whining, pacing, hyper-alert, or showing tension in their body. They might still take treats, but they’re working hard to hold it together. This is where most people think they’re doing desensitization, but outcomes are unpredictable: the dog might habituate, or they might sensitize. It’s inefficient at best, harmful at worst.

7-10: Flooding territory – The dog is over threshold and can’t function. They might be barking, lunging, cowering, panting heavily, or shutting down completely. They can’t learn in this state, and the risk of sensitization or trauma is high.

Now that you understand the zones, here’s how to recognize when you’ve inadvertently slipped into the risky middle or flooding territory.

So how do you know if you’re working your dog beyond desensitization levels? Pay attention to how the sessions feel and how your dog is responding. If training feels hard—like your dog is just barely holding it together, white-knuckling their way through, or you’re constantly working to keep them from tipping over the edge—you’re likely in that risky middle zone or beyond. Your dog’s body will tell you what their brain is experiencing, and it’s worth listening.

Signs you’re working beyond desensitization:

• Sessions feel difficult; your dog seems like they’re hanging on by a thread

• Your dog takes treats but spits half of them out, or stops eating halfway through

• Your dog can’t easily respond to cues, even ones with a strong reinforcement history

• Your dog’s body language is tense—stiff posture, whale eye, tight mouth, tucked or rigid tail

• Your dog is hyper-vigilant—constantly scanning, can’t settle, laser-focused on the trigger

• It takes a while for your dog to relax after the session ends

• You need multiple attempts to get your dog’s attention

• Progress feels inconsistent—some days seem okay, others fall apart

Understanding what desensitization actually means—and what it doesn’t—is critical if you’re working on reactivity, separation anxiety, sound sensitivity, or any other fear or frustration-based behavior. The difference between desensitization (systematic, sub-threshold exposure) and habituation or flooding (too-intense exposure with unpredictable outcomes) isn’t just semantic—it’s the difference between helping your dog genuinely feel better and risking making things worse.

If you’re wondering how to find that sweet spot where your dog is calm enough to learn, I wrote a blog about understanding your dog’s threshold that can help you identify a good starting place.

Working at the right intensity isn’t just important—it’s everything. It’s the difference between a training plan that works and one that backfires.

Next week, I’ll be diving into how desensitization applies specifically to separation anxiety and the power of staggered departures for dogs who struggle when left alone.

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Build the Foundation: Confidence Makes Desensitization Easier

One thing that makes desensitization more successful? A dog who already has baseline confidence navigating their world. Game of Bones is a 4-week interactive training course that builds your dog’s confidence through engaging mini-games. With real-time timer videos (it’s like having me in your living room coaching you), you and your dog will level up together in confidence, exploration, and adaptability. While it’s not a desensitization protocol, the mental skills your dog builds here—like handling novel situations and environmental changes—give them more capacity to stay regulated when working on their specific triggers.

[Learn More About Game of Bones →]

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Get Personalized Help with Your Desensitization Plan

Understanding desensitization conceptually is one thing—executing it correctly for your specific dog is another. If you’re struggling to find that sweet spot threshold, or you’re not sure if you’re in the 1-3 zone or the risky middle, let’s work together. I offer virtual behavior consultations and ongoing coaching through The Dog Lab. We’ll create a systematic desensitization plan tailored to your dog’s actual triggers and threshold, so you can stop gambling and start seeing real progress.

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