Read How Dogs Love Us: A Neuroscientist and His Adopted Dog Decode the Canine Brain Online
Authors: Gregory Berns
This turned out to be somewhat difficult. The normal structural scans couldn’t be completed that quickly, so we had to switch to a different type of scan. This one didn’t show as much detail, but we were able to find a combination of parameters that produced a usable image in under thirty seconds.
We spent an awful lot of time figuring out the best orientation of the brain. If you think of the MRI as being a digital bread slicer, we had to decide which way to cut the slices: left to right, top to bottom, or front to back. Since the human head is pretty close to a sphere, it doesn’t make a whole lot of difference which way you slice it. But a dog’s head, like the lamb’s, is elongated front to back and generally pretty flat from top to bottom.
As the images of the lamb’s head came up on the screen, we saw how little of the head was actually occupied by brain. Most of it was
nose and muscle. Those air pockets in the nose can wreak havoc with the MRI images too. Abrupt transitions in tissue density, such as going from air to skull, cause distortions in the magnetic field, which result in warped images. By carefully selecting the orientation of the slices, you can minimize this effect. Slicing from front to back seemed to give us the best results.
Anatomical images of the lamb’s head. The slices go from front to back. The eyeballs are visible in the top row, while the brain appears prominently in the middle and lower rows. The large black cavities are nasal sinuses.
(Gregory Berns)
Finally, it was time to attempt some functional scans, which are two-second glimpses of the brain in action. By continuously acquiring these functional scans while the subject does something, we can measure changes in brain activity. Think of the functional scans as the individual frames of a movie. Even though each one takes only two seconds, the subject might be in the scanner for half an hour during functional scanning. During such a session, we would acquire nine hundred functional images, at a rate of thirty scans a minute for thirty minutes.
Of course, the lamb was dead, so we didn’t expect to see much “activation.”
But we only needed to figure out how many slices it took to cover the brain and how to orient the brain for the most efficient coverage. Once we worked that out, Andrew and I recorded the sounds of the scanner running this sequence.
We could now introduce Callie and McKenzie to the actual noise they would experience in the scanner and gradually let them get used to it.
11
The Carrot or the Stick?
T
HE CHALLENGE OF ENTERING
the head coil and placing her chin on the boogie board chin rest had long been overcome. As soon as Callie heard the rustling of the plastic baggie containing bits of chopped-up hot dog, she knew. She would bound into the kitchen, wagging her whole rear end, and look at me with excitement and anticipation.
“Wanna do some training?” I would ask in a high-pitched voice.
Our training regimen had outgrown the basement. The only room in the house big enough to contain what was now a full-blown MRI simulator was the living room. Kat eyed the monstrosity in her living room, a space formerly occupied by an elegant sofa set and coffee table now pushed off to the side.
“There isn’t any other place for this?” she asked.
“It’s too heavy to move down in the basement,” I replied. “And I don’t think it will fit through the door.”
“You mean you constructed this in the living room without a way to get it out?”
“No, no,” I reassured her. “It comes apart.”
I had dusted off a PA system left over from my guitar-swinging
days in a garage band. As I set the speakers on a stand facing the tube, Helen came into the living room.
“What’s that for?”
“To simulate the noise of the scanner,” I explained. “It’s the only thing we have that’s loud enough.”
She nodded, and together we snaked cables from the speakers to the amplifier. We aimed one speaker at the side of the tube to simulate the vibrations that course through the MRI. The other speaker went at the end of the tube to achieve the full decibel level inside.
“Daddy?”
“Yes?”
“Can I come with you when you scan Callie?”
This question took me by surprise. I wondered what had motivated it.
“Why do you want to see the experiment?” I asked. “It might not even work.”
“I know, but I want to see it,” she said.
“Is it because you want to skip school?”
She turned away and mumbled, “Maybe.” But quickly recovering, she continued. “That’s not the main reason. I really want to see the experiment. Don’t you always say that real science is exciting? Wouldn’t I learn more there than I would at school?”
In that, her logic was flawless.
“I’ll have to think about it.”
I had no doubt that Helen would learn more about science watching this experiment than she would in an entire week of science class at the middle school.
This was Helen’s first year of middle school, and the transition from elementary school had been a shock for all of us. Her workload was so much larger than what she was used to, she still hadn’t quite figured out how to balance homework and fun. In addition to the
usual math, English, and social studies, her school required Latin for all sixth graders. In a classic case of confusing correlation with causation, the curriculum committee cited studies showing that kids who learned Latin did better on the SAT and reasoned that if all kids took Latin, their test scores would improve. Unfortunately, just because kids who take Latin have higher SAT scores doesn’t mean that Latin is the cause. These kids might already have a larger vocabulary and an interest in learning another language.
Latin wasn’t the problem, though. Much to my dismay, it was science.
Early in the year, I had tried to explain to Helen that science is always changing.
To which she asked, “You mean that this stuff is wrong?”
“Some of it.”
“Then why am I learning it?”
Because the state says you have to,
I thought. But what I said was “Science is a way of answering questions about the world around us. What you are learning is our current understanding of the universe. As we learn more, our understanding changes.”
“I still hate it.”
I understood her frustration. She really had tried to memorize facts of geology and the weather systems of the Mississippi Delta and Piedmont regions of the Southeast. But no matter how hard she studied, the science teacher seemed to throw obscure questions at the kids that I would have thought more appropriate for a high school or introductory college class.
The new semester had just begun when Helen asked me about coming along for the first scans. The next morning, we were standing at the bus stop.
“Do you have any tests this week?” I asked. Her face turned white.
“What day is it?”
“Tuesday.”
“I think I have a science test today.”
I was furious. “Helen, you just had a three-day weekend, and you didn’t study at all?”
“I forgot.”
“And, on top of that, you want to skip school to see the Dog Project?”
Her eyes were starting to tear up. “I know the material.”
“How can you know the material if you didn’t study?”
There was no answer to the question. She got on the bus, and I walked home frustrated that she wasn’t prioritizing her schoolwork.
Both Kat and I were ready to ground Helen as soon as she got home that night. In the past, when she received less than an 80 on her tests, she would lose computer privileges until she brought her grade up. While this had been an effective strategy to prevent her from wasting time on computer games, the time that was freed up didn’t generally translate into more studying. Computer time was exchanged for sulking time. She was well on her way to perfecting the art of the silent treatment.
From the day she joined our household, it was clear that Callie was an alpha dog. In Cesar Millan’s terminology, she wanted to be pack leader. She hopped on furniture whenever she wanted. When Lyra started to chew on a bone, Callie would dart in to take it away, only to drop it on the ground a few feet away, indicating that she determined who would be allowed to eat the “prey.” And when Callie settled into our bed at night, it was almost always in a position uncomfortable for the human occupants. The expression “let sleeping dogs lie” should have been broadcast above her head, because any attempts to move her to a more harmonious location were met with the most vicious snarling possible from the little creature.
Similarly, her insatiable appetite meant that all food had to be
pushed back from the edge of the kitchen counter. With her long snout, she could grasp any morsel of food within three inches, even if she couldn’t see it. She once licked clean precisely half of a pumpkin pie, which was the extent her tongue could reach. Every time we caught her with paws up on the counter, we yelled at her to get down. Although she complied with the command, it never prevented her from doing it again, usually within minutes.
It was this behavioral stubbornness that made us doubt Callie’s ability to participate in the Dog Project. I eventually realized that the problematic aspects of her behavior had nothing to do with her ability to learn. She could not only learn a complex task like going into the MRI scanner, she could actually learn to enjoy it.
I wondered whether something similar was going on with Helen.
Every time she did poorly on a science test, we used the equivalent of a squirt bottle or a shake can to curb the behavior: a scolding followed by a mild punishment. Punishment can be very effective in shaping behavior, but it works only when there is a credible threat of punishment present. This is so important, it bears repeating: only the
threat
of punishment can change behavior. As soon as the threat disappears, behavior reverts to its natural state. Punishment after the fact serves only to establish a credible threat in the future but does nothing to change what has already happened.
Helen’s lack of studying was water under the bridge. Grounding her would not change the inevitable poor grade she was about to receive. Would it make her study more in the future? Possibly, but only under the constant threat of punishment. There had to be a better way.
I asked Kat what she thought.
“I don’t like the idea of punishing our kids for not studying either,” she said.
“I wish Helen would want to study,” I said. “But if I had to study from that textbook, I probably wouldn’t do it either.”
“What can we do?” Kat asked.
“Maybe we need more of the carrot and less of the stick.”
We put our plan into motion at the dinner table that night. Not surprisingly, Helen didn’t think she had done very well on the test and picked at her food sullenly. Maddy sensed the tension and remained silent.
With great solemnity, I announced, “Mommy and I have been thinking very seriously about the Dog Project.”
Bracing for the inevitable hammer about to fall, Helen didn’t look up from her plate.
“Helen,” I continued, “you really want to see the scanning on the big day?”
“Yes,” she pleaded.
“Okay. Mommy and I have discussed this, and because this is so special and may never happen again, we want to let you go.”
“Really?” she exclaimed.
“This is important to you?” I asked.
She nodded vigorously.
“Good,” I continued, “because there is a condition.”
“What?” Helen asked.
“In order for you to miss school, you have to pull your science grade up to an A,” I explained. “If you have an A in the class, you can come. The Dog Project is very important to me, and I would really like you to be there to share in it.”
“I can do that!” she agreed.
For the next several days, the prospect of positive reinforcement had the desired effect. Although Helen still didn’t enjoy studying science, there was a noticeable decrease in homework resistance. She threw herself into making flash cards and made an earnest attempt to memorize the material. Kat and I patted ourselves on our backs,
celebrating our success at applying dog-training theory to preteen behaviorism.
But like dog training, the effectiveness is in the details.
Callie was making progress in the training in large part because I was beginning to learn how to make it clear what I expected of her. Baby steps, coupled with consistent reward, make for effective learning. But if the desired behavior is too difficult, then the reward becomes unobtainable and motivation declines.
With Helen, the desired behavior was clear: get an A. But what I had neglected to consider was the inherent unpredictability of her science teacher. I mistakenly assumed that if Helen put in the necessary effort, she would be rewarded with a good grade.
Big mistake.
A week later, despite all of her efforts, she returned home with a 75 on a quiz. This pretty much put out of reach the possibility of raising her grade to an A, at least by the time the Dog Project launched.
“I really tried,” she said. “He makes the tests too hard.”
Now Kat and I were in a difficult position. Helen had failed to achieve the goal we had set. If this were Callie, I would simply make her try again until she did what I wanted. But not only were we running out of time with the scan day a week away, but I also hadn’t accounted for an element out of my control: the fairness of the test.