What is Extinction

February 28, 2012

In behavioural terms, extinction is the lack of any consequence following a behaviour. When a behaviour is inconsequential (i.e., producing neither favourable nor unfavourable consequences) it will occur with less frequency.  When a previously reinforced behaviour is no longer reinforced with either positive or negative reinforcement, it leads to a decline in that behaviour.

In other words, if your dog has been reinforced for a behaviour, and that reinforcement is removed, the behaviour will eventually decline or extinguish.  Reinforcement does not necessarily always come from you but often comes from the environment.  For example, if your dog jumps on the kitchen counter top and finds food there, then jumping on the counter top behaviour will happen again.  Every time this behaviour leads to reinforcement it will become stronger.  You did not play an active part in this scenario.  “Catching the dog in the act” and punishing it will only result in the dog being more careful to indulge in this “counter surfing” when you (the punisher) are not present.  What will work in this case is to remove the reinforcement (food on the counter).  If the counter NEVER provides food for the counter surfer, the behaviour will extinguish.

Bear in mind, however, if a behaviour is either self-rewarding or rewarded by the environment, extinction will fail unless the trainer can consistently offer a better reward. Barking is frequently a self-rewarded behaviour. Waiting for a dog barking at passers-by to simply get bored from “lack of reinforcement” is an exercise in futility.  When dealing with self-rewarding or environmentally-rewarded behaviours, a combination of management, positive reinforcement, and negative punishment is an alternative solution.

Extinction Burst

Just before behaviour extinguishes it undergoes an “extinction burst”.  This means that the behaviour will become more and more intense just before it goes away.  If your dog barks incessantly to be let in and you decide to use extinction as a way of stopping the behaviour, be prepared for it to increase in intensity, duration and volume just before it extinguishes.  If you open the door at this point, you have reinforced the behaviour at its worst and this is what you will get next time.  The only way to deal with this is to carry on ignoring it.  Fit ear plugs, retreat to the furthest part of the house, and warn your neighbours.

Savvy trainers use this extinction burst as a tool when raising criteria in certain behaviours.  For example, say we are working on latency (speed) of the sit.  We ignore all the slow sits and only reward the fastest sits.  What will happen is that in response to the absence of reinforcement the sits will become faster as the dog’s sitting behaviour starts to undergo an extinction burst.  Because these more intense sits are the only ones that are being reinforced, the slower sits will extinguish and the better ones will increase.

http://en.wikipedia.org/wiki/Extinction_%28psychology%29

http://www.clickersolutions.com/articles/2003/extinction.htm

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The Retrieve as a Behaviour Chain

February 26, 2012

A marked retrieve is often considered something that a retriever does because that’s what retrievers do.  They go and fetch things and bring them back – sometimes….  In order to make this going and fetching things (birds or dummies) and bringing them back reliable and consistent we need to treat the retrieve not as a single behaviour, but as a complex behaviour chain consisting of a number of discrete behaviours linked together to form a continuous chain.

On the assumption that you are in line for a single marked retrieve, breaking down the entire behaviour into its component parts will probably look something like this:

  • Walking into line on lead.
  • Removing the lead
  • Getting into position in the line
  • Placing the dog in a sit (or stand) on your left (or right) hand side.
  • Checking the position of the gun or guns
  • Checking the position of the dog before indicating to the line judge that you are ready.
  • Marking the fall – both you and your dog
  • Sending the dog
  • Locating the dummy and picking it up
  • Returning to you with the dummy
  • Delivering the dummy to hand
  • Returning to heel if the delivery was made facing you.

Building the chain backward ensures that you are always moving toward reinforcement—the prize at the end of the chain—and that each part in the chain is strengthened, every time, by the cue for the next part.

Cues can be a number of things that tell the dog what comes next in the behaviour chain.  Cues can be verbal such as the cue “Sit”.  A cue can be a hand signal such as a hand extended to take delivery of the dummy.  A cue can be environmental – a bird or dummy lying on the ground which would cue the dog to pick it up.

It is important to note that a cue, if properly established, is a conditioned reinforcer.  Because the cue has been associated with a primary reinforcer many times, it becomes reinforcing by itself.  With the retrieve behaviour chain, therefore, the cues themselves reinforce the behaviour preceding them until the end of the chain where the big prize awaits – huge praise from the handler, a game of ball, or an extra special treat.

So, if you build the chain backward – starting with the last part of the chain, then the “return to heel” will reinforce the “delivery” will reinforce the “return to handler” etc. etc.

Back-chaining is useful for human tasks as well.  If you ever have to memorize a poem, a piece of music or a speech it is much easier to learn it in chunks starting with the chunk at the end and then learning the second to last chunk and so on.

Another important thing to understand about behaviour chains is that within a complex chain, such as the retrieve chain, you also have a number of “mini chains”.  Once you have taught the individual behaviours you can join a couple of them together as a mini-chain.  An example of a mini chain in the breakdown above would possibly be

  • Returning to you with the dummy
  • Delivering the dummy to hand
  • Returning to heel

This particular mini-chain would hold no matter what kind of retrieve is desired – be it a blind retrieve, or one of a series of marked retrieves.  And, because this mini-chain has received stacks of reinforcement during training (if you “back chained”) it will automatically reinforce the preceding mini-chain which would probably be the send off, the location of the bird or dummy, and the pickup.

I have used the word “cue” instead of “command” in recognition of the fact that there are many, many signals (or cues) out there that trigger various behaviours and that the cue does not necessarily come from the handler.  Environmental cues are extremely important to everyday life – think of how your approach home in your motor car cues certain behaviours in your dog.  For a dog working in the field with its attendant smells and sensations environmental cues are everywhere.  Many of our interactions with our dogs are cues that the dogs respond to whether we are aware of them or not.


Understanding Your Dog’s Signals Could Avert Tragedy

February 14, 2012

I’m not sure if the media is just more aware of dogs that are biting humans, or because dog bites on humans are increasing.  Just recently here in South Africa, a “service” dog bit a child quite badly, and even more recently a dog in the US bit a young anchorwoman.  This video has been aired quite extensively.  Jennifer Shryock, who does a lot of work in the United States with dogs and kids and has studied dog body language has commented on the video of the dog bite to the anchor woman in terms of the signals that the dog was sending and that were being ignored by all present, including the owner.

Have a look…

What is extremely important for anyone who approaches a dog, particularly a strange dog, and particularly if you are teaching your child about dogs, is to become familiar with how dogs communicate their anxiety and discomfort.  This video clip quite clearly illustrates many of the more obvious ways a dog will communicate it’s state of mind.

Try to REALLY look at dogs and try and understand what they are saying.  The really sad thing is that so many dog bites can be avoided if we just learned to read what our dogs were trying to tell us.


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