Habituation - how and why the science is flawed

Respect and Densensitizing
November 15, 2017

More than twenty five years ago, Wayne  Bryden, a professor at Sydney University, gave me a book on the science  of learning theory. In it I first read about habituation. I could never  work out how habituation fitted with my approach to horse training. It  made no sense to me then and it makes no sense to me today. After thirty  years I've finally put into words why I believe there is no such thing  as habituation in relation to training horses.

Pressure  and relief forms the basis of horse training. Pressure is something  aversive that the horse wants to get rid of. The horse finds relief  when pressure is removed.

Here are some examples:

A  rider puts his leg on – pressure – the horse moves forward and the  rider immediately takes his leg off – relief. The horse learns to get  rid of the rider's leg by moving forward.

A  rider pulls on the bit – pressure – and when the horse slows, the rider  gives – relief. The horse removes the pressure of the bit by slowing.

A  handler asks a horse to step over a log but the horse stops. The  handler taps the horse's rump and pulls on the lead rope – pressure.  When the horse steps over the log, the handler stops tapping and pulling  – relief. The horse relieves the pressure by stepping over the log.

In  each of these examples the horse learns to relieve pressure. In  scientific terms, the subtraction or relief of pressure is referred to  as ‘negative' i.e. pressure is taken away. The removal of pressure at  the appropriate time reinforces a behaviour, or makes it more likely to  happen again. Hence the term ‘negative reinforcement'.

When  a trainer uses negative reinforcement consistently, the horse learns to  relax because there's always a simple way to relieve pressure.

Good  trainers also use ‘shaping' to teach horses. Take the example of  teaching a horse to spin. The trainer starts by teaching the horse to  stop his inside back leg and take one step around. When this is  established, the trainer asks the horse to take two steps around. The  next lesson may be three steps and over weeks and months the steps are  gradually increased until the horse steps around full circle and spins.

The  targeted behaviour – the spin – is ‘shaped' in small increments. One  step becomes two, two steps become three, three become four and so on.  Shaping and negative reinforcement form the basis of most horse  training.

It's proposed by many  scientists and horse trainers that a completely separate process –  habituation – can also be used to train horses. The scientific  definition of habituation is: The waning of a response to a repeated stimulus as a result of frequent exposure (not fatigue).

In other words, expose a horse repeatedly to something he's afraid of and he'll get ‘used to it.'

All  over the internet, and in every horse magazine you pick up, there are  people supposedly ‘habituating' horses. Their idea is to repeatedly flap  flags, tarps, ropes or something else at a horse and he'll become  ‘habituated', ‘desensitised' or ‘used to it.'

There are more than a few problems with this theory.

In  every situation, horses try to find a way to relieve pressure; they  always look for the easy way. To flap something continuously means that  the horse is under constant pressure with no relief and no escape. The  rules have changed – the horse has no way to relieve the pressure.  Whether the horse moves, stands, kicks or rears the trainer just keeps  flapping in the belief that the horse will ‘get used to it.'

The  trainer is thinking one thing and the horse is thinking something  totally different. The trainer thinks, “It's ok, I'm habituating him;  I'm desensitising him; he'll get used to it.” The horse thinks “How can I  get out of this terrifying situation? How can I stop this person  flapping things? What do I have to do to make him stop?”

In  the wild, a horse won't subject himself to a frightening situation. He  immediately runs away if something frightens him. He can relieve  pressure any time he chooses by running away.

Here's a quote from a paper titled Punishment in horse-training and the concept of ethical equitation by Paul McGreevey BVSc, PhD, MRCVS, MACVSc (Animal welfare) and Andrew N. McLean, BSc, PhD.

“…..gaining  control over aversive stimuli is of vital importance to animals. When  such control is thwarted, the animal's well-being is threatened and  neurosis may develop. Hence, extra care must be taken when training  animals using aversive stimuli because of animals' imperative to achieve  control over such stimuli. Solomon (1964) showed that maladaptive  behaviour arises when:

  1. 1. There are sustained raised levels of arousal;
  2. 2. The aversive stimulus is unpredictable;
  3. 3. The aversive stimulus is uncontrollable; and
  4. 4. The aversive stimulus is inescapable.

Numerous studies attest the problems that emerge when these conditions arise…”

The  four points noted by Solomon occur every time a horse is exposed to  frequent and repeated stimuli without any way to relieve the pressure.  e.g. When a horse is saddled for the first time and let go to buck; when  a dummy is tied to a bucking horse; when a trainer repeatedly flaps a  flag, tarp, rope or other paraphernalia at a horse. In all these  situations there are aversive stimuli that horses find unpredictable,  uncontrollable and inescapable.

Instead  of exposing horses to frightening stimuli, negative reinforcement and  shaping can be used to overcome a horse's fears and to introduce  everything to every horse without frightening them. A different process,  if indeed one exists, isn't needed.

Take  the example of mounting an unridden horse bareback for the first time.  The trainer first lays his arm over the horse's back. The horse is  worried by this pressure and wants to get rid of the arm from his back.  When the horse stands for a few seconds, the trainer removes his arm and  steps away and the pressure is relieved.

Next,  the trainer jumps up and lies across the horse's back. Again the horse  is worried and wants to remove the trainer from his back. If the horse  moves a few steps, the trainer maintains his position. Immediately the  horse stands, the trainer dismounts. The horse has a way of removing  pressure – a rider – from his back. Stand still and the rider dismounts.

On  the next approach the trainer lies across the horse and moves his leg  and knee to the top of the horse's back before dismounting. The horse  knows how to relieve the pressure – stand and wait for the trainer to  dismount. This is negative reinforcement at work.

The  trainer is also shaping the horse's behaviour. First, the horse learns  to stand when the trainer lays his arm over the horse's back. Next step  in the shaping process is for the horse to stand when the trainer lies  over the horse's back. Next, the trainer moves his leg and knee to the  top of the horse's back.

Just as a  trainer shapes a horse's behaviour when he teaches him to spin, the  trainer shapes the horse's behaviour to accept a rider. Each step is an  extension of the previous one and the trainer always dismounts before  the horse becomes frightened or confused.

Each  advance of the trainer's position is a step in the shaping process and  each retreat is a relief of pressure (negative reinforcement). The two  processes combine to produce the desired outcome. The trainer continues  the advance (shaping) and retreat (negative reinforcement) until the  horse accepts the trainer sitting on his back.

The  trainer also shapes the amount of time he spends on the horse's back.  At first he sits only a few seconds before dismounting. Next, he sits  for a few more seconds before he dismounts. Next approach, the time is  again extended. And so, time is shaped, or extended on each approach.

The  horse learns that the pressure doesn't go on forever. He knows that if  he keeps standing, the trainer will eventually dismount. Over a couple  of lessons, the horse waits longer and longer for the trainer to  dismount and eventually accepts the trainer on his back indefinitely.

The  horse has not been ‘habituated', ‘desensitised' or become ‘used to' a  rider. The horse's response did not wane as a result of ‘frequent  exposure.' Instead, the horse's response waned because the trainer's  approach was always predictable and escapable. The horse learned how to  remove the trainer from his back and it worked every time.

If  the trainer dismounts without frightening the horse, one exposure is  enough to introduce each new position. The horse will always accept the  trainer in the same position on the next approach.

One  exposure, negatively reinforced at the appropriate time, will teach the  horse to accept the trainer in that position. It's not ‘frequent  exposure' that makes the horse accept the trainer; it's the fact that  the trainer dismounts – relieves the pressure – at the appropriate time.  The horse relaxes with the process because he's found a way to relieve  pressure and each advance of the trainer's position is kept within the  limits of what the horse can accept without being frightened.

Negative  reinforcement and shaping are effective in all areas of horse training  and can be used to introduce everything to every horse – saddle, girth,  raincoat, stockwhip, lasso rope etc. or to catch a horse for the first  time, handle his legs or load him into a trailer. Negative reinforcement  and shaping can also be used to overcome a horse's fear of spray  bottles, clippers, needles etc. or anything else you may want to do.

If  negative reinforcement and shaping are used in every training  situation, there is never a need to push any horse to the point where he  becomes frightened, confused and stressed.

I  believe that habituation, as defined by science, does not exist in the  context of horse training. And whether it exists or not, there is  absolutely no excuse for flapping things at a frightened horse at any  stage of his training.

READ MORE ON THIS SUBJECT HERE: www.fearfreehorsetraining.com/blog/kick-the-habituation-habit

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