The "Why" of Fear Related Aggression, Part 1: Early Trauma

Lisa Radosta, DVM, DACVB
Published: January 30, 2013
The "Why" of Fear Related Aggression, Part 1: Early Trauma

One of the most common questions I am asked in my clinic is, "Why does my dog act like this?"

In all aspects of our lives we get very caught up in the "why?" If we can figure out why something happened, maybe we can figure out how to fix it. Possibly, we can make sure we do not make the same mistake the next time.

I don’t always have the answer to that question for every owner who comes into my practice. In most cases, I can identify an underlying cause. In almost all cases I can come up with a couple of hypotheses for what was likely to have caused the pet’s behavior.

We are going to take a look at the causes of fear related aggression in today’s blog. It is the most common type of aggression I see in my practice. There are four general influences which cause the development of this disorder: heredity, traumatic incident (including pain), lack of socialization, and the influences of learning.

Some patients have more than one influence. As you would expect, those cases can be harder to treat.

We have already talked about socialization enough that the readers could write a blog on it, so we won’t cover that now. Let’s talk about traumatic incidents and their influence on pups during the important developmental periods.

Remember that trauma is in the eye of the beholder. For example, when I stub my toe on Maverick’s Nylabone, it hurts, but I forget about it pretty quickly. When my daughter did the same recently, it took daily Hello Kitty band-aid changes and was a topic of discussion for days. Same incident, two different perceptions.

Back to your pup. If your pup is scared by a stranger with a hat on during the socialization period, that may count in his mind as a traumatic incident, which will shape his behavior for his entire life.

There was a recent study published in Translational Psychiatry which showed that rats that were exposed to a fear producing stimuli before puberty actually had changes in the expression of the genes and in the neurotransmitters in the brain. These changes made them more likely than rats that were not exposed to a stressful stimulus when young to display aggression toward other rats in the future, even if those other rats were not associated with the fear producing stimulus. Are you wrapping your head around this?! If the rat is scared during critical developmental periods, the brain, how the genes are expressed, and the neurotransmitters change! These changes make it more likely to be aggressive toward innocent rats! Does this sound like any dogs you know?

It is realistic from what we know about dogs to assume that these changes most likely occur to some extent in their bodies as well. This is one of the many reasons why fear related aggression doesn’t respond well to obedience training. It is not an obedience problem. It is an emotional problem, which is mediated at least in part by the neurochemicals in the brain.

I meet many dogs who are obedient but are still fearfully aggressive. So, that is the 1st "why" of fear aggression. Next week, we will discuss another "why": The power of learning.

Dr. Lisa Radosta

Image: Art_man / via Shutterstock

Last reviewed in August 3, 2015

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