Monday, March 24, 2014

Three things I learned: the neurophysiology of canine anxiety

Positive early experiences can help all dogs, but especially anxious dogs, cope better in potentially stressful situations.

Last week we attended a presentation on the Neurophysiology of Anxiety and Its Management – in dogs that is. Dr Andrew O’Shea, head of the University of Sydney's veterinary behaviour service, gave a very detailed talk about the physiological basis of anxiety, and the way this impacts on canine behaviour.

One thing I learned is the scale of difference in the CNS of humans vs dogs. According to Dr O’Shea, the dog brain has less than 1 billion neurones and less than 140 million neurones in cortex (cats, incidentally, have 100-200 million more neurones than dogs)(wondering who counts these and whether they have to start again if someone disturbs them mid-count). The average human has around 86 billion neurones, 23 billion of which are in the cortex. Intelligence is thought to be related to the number of interconnections within the brain. The average dog has less than one trillion. We have around 10,000 trillion (and I'd be pretty devastated if mum walked in and offered me a cuppa mid-count on that one).

Point being that dogs don’t have the structures in their brains to be vindictive or hold grudges.

The second thing I learned is this thing called an aggression ladder (you can download a PDF about it here). At the bottom, we have a relaxed dog.

Then there are other behaviours progressing from subtle to outright aggression. These are:
  • Yawning, blinking and nose-licking
  • Turning the head away
  • Turning the body away, sitting pawing
  • Walking away
  • Creeping the ears back
  • Standing crouched with tail tucked under body
  • Lying down with one leg up
  • Stiffening up, staring
  • Growling
  • Snapping
  • Biting

According to Dr O’Shea, dogs learn to go from the relaxed stage straight to biting when they realise we don’t read their body language well.

It is not a ladder of aggression: it’s the body language of fear. And it is controlled predominantly below the cortex (the bit of the brain that does the thinking, cognitive work and problem solving). The dog doesn’t have much conscious control of it.

The third thing I learned is that a person skilled in veterinary behaviour spends a lot of time defining and reframing problems to help solve them. And that is necessary because our ideas about anxiety in animals can be completely off the mark.

According to Dr O’Shea, fear is a normal automatic emotional and physical reaction in response to an imminent threat. It leads to an animal fleeing, fighting or freezing – abnormally it may lead to the animal fiddling (e.g. cyclic repetitive behaviours out of context). Fear can be wound up or down.

Anxious behaviour is a normal automatic emotional and physical response due to the apprehensive anticipation of a future threat. It prepares the individual to react faster and possibly better if the threat should become imminent. It should be short-lived.

In a novel situation, a normal animal will try on different behaviours and, if these lead to a good result, repeat them. If they lead to a bad result they will try a different behaviour.

In Dr O’Shea’s words, that normal animal will investigate the novel environment until it has enough information to trigger a memory (it takes 1/20 of a search the memory banks). If no memories are triggered, they try something.

An anxiety disorder involved an abnormal, automatic, emotional and physical response to an apprehensively anticipated future threat whenever the individual does not know how to behave to get a predictable response.

It is probably due to an excessively reactive amygdala and a damaged hypothalamus.

In a novel environment, an animal with an anxiety disorder still gets the same information. If they have a memory that tells them what to do, they do it. But if there is no memory, they apprehensively anticipate “that the world is going to end.”

What we see in these situations is a partially turned on fear response and a very activated amygdala which gets bigger in size and becomes easier to activate. These dogs are hypervigilant because the diffuse modulatory systems in the brain are turned up…to eleven.

If an animal is not socialised properly and has a poor bank of memories in the brain, they have fewer memories to tell what to do in a situation to get a good outcome. They tend to react a lot more.

Prevention involves selection of dogs with a non-anxious phenotype (and avoiding breeding those with anxiety disorders), early best-practice socialisation (stuffing the cortex full of good experiences and good results) and – although Dr O’Shea didn’t say so explicitly, I took it as implied – making a point of trying to be more observant and understanding of our canine companions.

Up to one in five dogs will develop an anxiety disorder, but at the age of eight weeks it can be impossible to tell which ones. Dr O’Shea recommends puppy preschool for everyone, as it is one way to provide positive experiences and memories to help them cope better later on. Its also good for the other end of the leash - these early bonding experiences teach humans to read their canine companions better, and respond more appropriately.

Awesome dogumentary
If you love dogs and haven't yet seen it, The Secret Life of Dogs is worth a look for the cinematography alone. As they say, "They're so familiar to us, we can forget how extraordinary they are". Its not a short clip - it runs about 46 minutes - but absolutely worth every minute. If the video is not showing on your device, click here.