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This is the limitation of behaviorism: one can never truly know why a person or animal does something. You can only observe the effect of a reward or punishment and whether it increases or decreases a particular behavior. In fact, hard-core behaviorists completely dismiss what goes on in an animal’s head. Since behavior is the only thing that matters to a behaviorist, subjective thoughts and emotions become irrelevant. But if you have tried to curb a dog from a particular bad behavior—chewing furniture or shoes, for example—you know the frustration of trying to understand why none of the punishments are working. How many dog owners have cried out in vain, “Why are you doing that?”

I hoped the Dog Project would someday be able to answer that question.

Until that day, Mark and I would need to figure out a training protocol based on conventional behaviorist methods that would get a dog to willingly climb in an MRI machine.

I met Mark at CPT. The training facilities are basically a large room. The linoleum flooring makes for easy cleanup of the inevitable “accidents.” Apart from a teeter-totter and some ramps and hoops for agility training, the room is devoid of furniture. The spartan decor minimizes dog-induced damage expenses.

Mark was wearing his standard attire for dog training: a polo emblazoned with the CPT logo, athletic shorts, and ru

From the begi

Natural behaviors are ones that dogs do on their own. Walking, sitting, and lying down are natural behaviors. If the dog has a drive to hunt small animals, then tracking might be considered a natural behavior too. Retrievers were originally bred to retrieve ducks, so they have a natural drive to carry objects in their mouths and, at least in theory, return them to their handlers. For some dogs, swimming is a natural behavior. For others, water is to be avoided at all costs.

It is safe to say that going into an MRI is not a natural dog behavior. Most humans don’t like it either. But Mark explained how we could train a sequence of behaviors that were mostly natural for the dog.

“Most of what the dog has to do is a ‘down-stay’ position, correct?”

In a “down-stay,” the dog lies down and stays in that position while the handler remains some distance away.

“Yes,” I replied.

“Lying down is a natural behavior, so that is easy to teach with positive reinforcement. What else does the dog need to do?”

“He needs to hold his head perfectly still,” I said.

“How still?”

“Less than two millimeters of movement for periods up to twenty seconds.”

Everything depended on the head being still. Any movement would render the MRI data useless. When we perform scans on humans, the subject lies on her back with her head surrounded by foam pads. Most people are able to remain still, and the foam makes it easier. But a dog might not like his head being encased in foam. Maybe something less intrusive would suffice.

“We could make a chin rest for the dog,” I suggested.

Mark liked this idea. “When we train dogs for tracking, we will often teach them a ‘touch’ command where they touch their nose to a target. We could do the same thing to teach a dog to ‘touch’ a chin rest.”

Dogs use their nose to touch and sniff everything. This was a brilliant example of taking a natural behavior and turning it into a trained one. That left only the noise. MRIs are as loud as a jackhammer.



Mark stressed the importance of subject selection. He said, “We will need to carefully select the first subjects for the right temperament characteristics.” With the right subjects, the training would be easy. We certainly didn’t want a situation in which the dog didn’t want to be there. Even if we could train the dog to stay in the MRI, if he didn’t want to be there all we would capture would be an anxious dog brain.

Because the patient table of the MRI is elevated, the ideal dog would be unafraid of heights, let alone enclosed spaces. Because we would most likely be studying several dogs, the ideal subjects would need to be social. And because there would be different people at the sca

In Georgia, thunderstorms occur with regularity during the spring and summer. I don’t know if there is a higher proportion of dogs with thunder-phobias in the Southeast, but it is very common in Atlanta. Even though the MRI doesn’t sound like thunder, an existing negative association to loud noises might make training difficult. As long as the dog didn’t have a noise phobia, we could gradually acclimate him to the specific type and volume of noise the MRI makes.

“The dog should be calm,” Mark said. “And he should be unafraid of novel environments.”

I had no grant funding to do this. Everyone was volunteering, but it still cost $500 an hour to rent time on the MRI. I had a small amount of discretionary research funds, but to keep costs down, we couldn’t burn up sca

“The most important trait,” Mark said, “is motivational drive.”

“What do you mean?” I asked.

“The dog has to enjoy the training. If he isn’t having fun, it is much harder to shape behaviors.”

Thorndike’s first law. The more the dog likes something, the stronger the S-R relationship.

“Do you know any dogs that meet all these criteria?” I asked.

“I know some that compete in agility trials,” he said. “But the owners can be a problem. If the owner isn’t motivated to do the training, then the dog won’t be either. A lot of people in the dog world have their own ideas about training. For this to work, we will want the training protocol to be consistent between dogs and owners.”

I hadn’t thought about the human side of the equation. Getting people to do what you want is a lot more difficult than getting dogs to. If Mark could do all the training, that would solve the problem, but he still had a business to run. What if I, or Andrew, learned how to train dogs? I wondered whether Callie could do this. She certainly wasn’t calm. But she was highly motivated by the prospect of hot dogs. The idea of training Callie to go into the MRI seemed unlikely, so I kept that thought to myself.

Mark had been in dog training for a long time, and he knew a lot of dogs and owners in Atlanta.

“I have a few people in mind,” he said. “Let me talk to them and get back to you.”

I was excited. I didn’t think anyone in the dog world would take the idea of sca

5

The Sca