The Science Behind Desensitising Your Dog

Desensitisation is a tool that may of us use in dog training. It can be used preventively, but it can also be used when our dogs have become sensitive to the world around them.

But why does desensitisation work?

And, more importantly, what kind of things does it work with?

Are there places where it doesn’t work or we’ll struggle?

If you’ve ever wanted to know why desensitisation is so effective, you’ll find your answers here. You can also find other posts in this series:

• what desensitisation is
• how to get the most out of it
• questions people ask about desensitising their dogs

Sensitisation is designed to be a temporary process

Evolution has endowed us with an incredible advantage. Instead of having to learn the hard way that something coming towards your head at high speed might knock you out, it gave you the reflex to duck.

When you dive into cold water, your heart and lungs change from the job they were doing so that your plunge does not deprive you of oxygen.

And when you step into sunlight, your pupillary muscles contract so that the light doesn’t burn your retinas.

What a marvel the animal body is!

We come with preconfigured programming so we don’t have to learn to startle when there’s a loud noise, to blink when things threaten to blow into our eyes and to sneeze if irritants enter the nasal cavity.

These reflexes have been so important to our survival that they are passed on from generation to generation.

Sensitisation can be emotional

Why are so many humans afraid of heights and the shame of speaking in public? Why do 3% of us feel uncomfortable around blood or vomit?

When you think about it, you don’t have to do much before you realise how useful these skills can be.

After all, falling from a height will kill you. Shame in humans can lead to ostracising and social rejection. Blood and vomit can carry communicable diseases.

When you gather up the wealth of human experience and assess what people are afraid of, it’s often things that are potentially dangerous. There’s nothing silly about that. Being afraid of snakes, spiders, stinging insects and things falling from the sky probably saved our ancesters at some point.

Since emotions energise action and add urgency to behaviour, these fears have adaptive value.

Although these are not the same as reflex responses like your pupil dilating or contracting, they have undoubtedly benefited us through generations.

Research isn’t decided on what to call these. Some call them biologically relevant stimuli. Others call them phylogenetic or species memories. Although not everyone will experience them, they are so common that we realise it’s more than chance.

Emotional sensitivities for dogs

Our dogs also have their preconfigured reflex-like responses to biologically relevant stimuli. Not every dog will struggle with them. They’re not like the sucking or rooting reflex of a puppy. Even so, there are fears which are very common for dogs.

Some of those fears involve strange humans or dogs. It’s hard sometimes to remember that dogs are not really that evolved, time-wise, from wolves. Seeing an intruder on your territory is a threat to a wolf.

Selective breeding and socialisation have changed this for dogs, but just like us, it doesn’t take much for those fears to be reawakened.

Social entities are not the only source of canine fears. Loud noises like fireworks, gunshot and thunder are very common fears for dogs. They can also startle as we do to unexpected touch. Like some humans, a few dogs can be very fearful of flying insects, especially if they’ve been stung in the past. Restraint is not just uncomfortable for a dog: it can cause a profound sense of panic.

These social and non-social fears are very common across the species. That’s not to say all dogs will have them. Nor is it to say that they will become pathological fears or phobias that require medication.

Even so, they are more common than you’d think.

Biologically relevant fears

Since the 1980s, psychologist Susan Mineka has been studying fear. She works most often with macaques and with humans. What she found in one very interesting piece of research with Arne Öhman was that it was easy to teach macaques to be afraid of snakes, even if they’d never encountered a snake before.

It did not take much to awaken those deep-seated, evolutionarily inherited responses.

She paired up seeing the snakes with a mild footshock. She also paired up other stimuli including mushrooms and flowers. It was much easier for macaques to learn that a snake predicted a shock. The same was true for humans too. We also find it much easier to learn that snakes predict shock compared to a mushroom or a flower.

Lots of animals have these biologically relevant fears. A rat in a lab who has no experience of cats will still be afraid of cat odour many, many generations after their last ancestor would have encountered them.

It’s not simply that we learn to be afraid of these more easily. It takes fewer bad encounters with a wasp than it does with a sheep, for example, to learn to be afraid of wasps.

It’s also that some of these fears, once awoken, can be very hard to inhibit.

Why do we sensitise to things?

Normally, when things in the world startle us, we reset after a time. However, sometimes we can become more sensitive.

For instance, when I was a teenager, my younger brother used to wait behind doors and leap out to startle me. That was really effective at sensitising me and I spent much of my time at home waiting for him to inevitably try to make me jump.

But why do we get used to things sometimes and at other times, we become more sensitive to it?

Why can someone live right under a flight path and barely notice the loud noises, and why do other people notice every single plane that passes?

Usually, there are four reasons.

The first is prior arousal. If we were anticipating something beforehand, it makes us easier to sensitise. This isn’t just for things to be afraid of, but also things that are a lot of fun. Fairground rides and movies play off this arousal, knowing that if they prime us, we’ll jump more, we’ll startle more, we’ll laugh more.

The second is an intense emotional state. If we’re really excited or joyful, that makes it just as easy to sensitise as being really afraid.

The third is repeated, unpredictable exposure to full-intensity stuff – just as my brother did with me.

The fourth is developmental stage. Some fears are just more relevant to us at certain impressionable ages.

It also goes without saying that if we’ve sensitised in the past, it makes it easier for us to sensitise again.

Preventing sensitisation

When we know that there are things in life that it’s easy for us to sensitise to, we can ward that sensitisation off. Much of early socialisation and habituation for young puppies is like that. It takes advantage of the fact that young animals haven’t developed those natural fears yet.

If they have enough positive exposures to noise, to movement, to new experiences and to the things that are biologically relevant to their species, we can habituate them so well that this familiarisation lasts a lifetime.

For instance, my dog Heston was like this with cars. He had so many non-events with cars on the road where they were just doing their car thing and we were just doing our puppy-and-human thing, that passing cars became really insignificant to him.

That early learning lasted a lifetime. He never, ever reacted to passing cars.

Compare that to my dog Flika. She arrived with me when she was 14 and cars really disturbed her. She’d had a lifetime of sensitivity to them and it was really hard to help her habituate to them.

Heston had his early familiarisation working in his favour.

Doing so at low intensity, when the dog is in a fairly neutral emotional state can really help.

Preventative habituation

Although we take huge advantage of those early weeks up until around 10-12 weeks of age to make sure our puppies are exposed at low intensity to things, we can make this a lot stronger with three key strategies.

The first is to make sure the puppy has the option to move away and to take their time exploring if they want. Ideally, doing it at such low intensity that they barely notice it will help. For instance, when I raised orphaned litters of kittens, I often vacuumed the rooms around them and allowed the kittens to explore the vacuum. I also did that with the washing machine and other loud household noises.

This is not just true of loud noises. It is also important with handling and restraint. If this is the way that things always are, then our puppies are much more likely to get used to things, especially if we introduce them in low doses to start with.

And it’s also true for unfamiliar animals and humans. This way, we can avoid our dogs becoming fearful of the most common things that dogs can become sensitive about.

After all, we know that thunder, fireworks and loud noises are mostly benign. We know that most strangers are friendly, including a lot of unfamiliar dogs. And we know that handling is benign too. This includes things like wearing harnesses and collars.

This is also true for things that are likely to be really exciting for our dogs, like movement or birds.

Many people get this wrong by trying to ‘socialise’ an excited or anxious, over-aroused puppy to whatever it is they’ll be likely to struggle with in life. They do so in uncertain surroundings, making it incredibly likely the puppy will sensitise to movement or to other animals.

When it’s too late

When our dog has sensitised to something, our first question is whether they’ll simply naturally reset.

For example, every Fireworks season, Lidy becomes progressively more sensitive to noises – even if they’re very far away and barely audible. She also generalises, making it much more likely that she’ll be anxious around cars backfiring, gunshot or even bins being moved.

But once things settle down again, most of those noises are ones that she normally and naturally habituates once again to.

Sensitisation is often, not always, a temporary process.

When it’s less likely to be a temporary process is with those biologically relevant things in life: strangers, strange dogs, loud noises, insects, snakes and restraint. It’s also less likely to be truly temporary if they’ve already been sensitised to those things in the past.

This is where we can give our dogs a helping hand through gentle and gradual exposure. When we do so at low intensity, in times of neutral or mild emotion and when our dog is not too aroused, it is much more likely to work.

Sensitising to excitement

We can also sensitise to exciting things too. This also can happen with things of biological relevance to our dogs. Things that move can be tough for herding dogs, be they corgis, collies, cattle dogs or shepherds.

That’s not just cars. It can also be cyclists, skateboarders and joggers.

And it’s not just herding dogs. I once worked with a bulldog who was very, very sensitive to wheelie bins!

Wildlife and livestock can be difficult for some dogs. Once sensitised to the sight or smell of birds or larger animals, it can be very difficult for our dogs to learn to relax around them.

These become enormously powerful predictors of joyful experiences for our dogs and they can then become very sensitive to anything that predicts a chase.

Desensitisation with excited dogs is much more challenging because it is so arousing in itself. Therefore, it can be really important to work a little differently with dogs who have sensitised to all the things that are thrilling in life. That can be very tough.

Other things we can do

There are plenty of other Lighten Up resources that can help. This whole series on the Resilience Roadmap is available on the website.

You can also find this paid short course on the Roadmap if you’re looking for support. Using conditioned safety cues can also help our dogs if they are struggling with anxiety.

Of course, having a good skillset and being able to disengage is also important. You can find the 42 Lighten Up Skills for Resilience on this short course.

This article is part of a series on desensitisation.