For the Love of a Dog (44 page)

In mammals and birds, these primitive circuits appear to be the flip side of the pathways related to social attachment. In other words, the brain’s ability to create feelings of love and attachment entails the ability to feel panic, and eventually sadness, when the object of our affection goes away. The proposition that the brain commingles love and grief is supported by the ability of oxytocin—the hormone associated with love and attachment—to soothe animals suffering from separation distress. Take a duckling away from its mother and it will call for her in a panic. Give the duckling oxytocin and the calls quiet, while the duckling settles as contentedly as if cuddled beside her mother. This phenomenon is not unique: extensive research on social mammals shows that their neurophysiology resembles ours when it comes to social attachments and separation distress. In extreme forms, this distress verges on panic, as I inadvertently implied when I wrote, long before Luke died, that “I imagine his death to be as if someone took all the oxygen out of the air and I was left to try to survive without it.”

Not only are these panic circuits primitive things, it turns out they are derived from the primordial pathways that mediate pain. The
same parts of the brain activate when an animal is physically injured and when it’s distressed about a separation. Additionally, opiates, such as morphine and codeine, alleviate separation distress and panic attacks, even though they are classified as painkillers. The experience of pain and the loss of social contact are so closely aligned in the brain that the administration of morphine actually reduces sociality in mammals: rodents spend less time with others, dogs wag their tails less, and primates groom less often if you give them a healthy dose of it. That’s one of the reasons why addictions to this class of drugs can be so dangerous—people who become seriously addicted to morphine actually go out of their way to avoid social contact. Their brains are telling them they’re getting more than they need, when in reality they’re completely alone. The opposite happens if you decrease the levels of opiates in the brain—individuals seek out social contact and, if the opiate levels get low enough, can’t seem to get enough of it. Thus, the chemicals that reduce physical pain also seem to provide us, at least temporarily, with the same feelings of well-being that healthy social relationships provide.

No wonder we talk about
the pain
of losing someone we love. The relationship between grief and pain is not merely metaphorical; anyone who has lost someone they loved deeply, whether a human or a dog, instantly understands the connection between grief and an actual sense of physical pain. After Luke died—and after my mother died, only six months before him—I remember feeling as if I was recovering from surgery, as if I had a raw, tender incision deep in my belly. It’s no accident that we care for people who’ve been injured the same way we care for people who’ve suffered a loss: we bring them flowers and cook our best comfort food, which we deliver with sympathy cards and gentle, warm hugs. Whether someone is grieving over a death or has been hurt in a car accident, we call the process of their recovery “healing.”

However, it’s one thing for animals to feel emotional distress because they’ve been separated from their mothers or their mates. It’s another thing altogether for them to fully understand that the separation is permanent. Surely it’s the knowledge that the dogs we’ve lost are never coming back that makes our grief so intense. It seems in this case that the more sophisticated our ability to think, the stronger and more
painful are our emotions. This connection between thoughts and emotions is a critical part of how we experience the world, and if we want to compare our experience with that of our dogs, it’s worth taking a moment to look at new discoveries about the synergy of thoughts and emotions.

One of the most interesting aspects of the connection between thinking and emotion is the newly discovered importance of emotions in decision making. Certain areas of the brain integrate emotion and reason; if they are damaged—usually this happens as a result of head trauma or surgery—the victim is unable to make even the simplest decision.
⁴
She can create a complete list of possible options in the face of any challenge, but is unable to come to a conclusion about which one to choose. She can pass any intelligence test and solve difficult mathematical problems, but she can’t make a decision.

One such patient, named Elliot in Antonio Damasio’s book
Descartes’ Error
, was an upstanding husband, father, and professional until a brain tumor necessitated the removal of the area of the brain that integrates emotion and rational thought. Although he performed perfectly on a raft of intelligence and personality tests, he became nonfunctional at the office. Unable to decide anything, he’d spend an entire day at work devising new ways to sort documents that could’ve been filed in five minutes. He seemed completely unaware of his disability. His social skills fell apart, too: he’d blurt out rude and hurtful remarks, with no idea of their effect on those around him. Eventually, Elliot lost his job and his family and ended up bankrupt and alone. When his emotions were no longer able to advise the rational part of his brain, Elliot was unable to function.

Patients like Elliot have taught us how vital the emotions are to our abilities as humans to make good,
rational
decisions. Long dismissed as somewhat embarrassing remnants of our animal nature, emotions have traditionally gotten, in the words of the late comedian Rodney Dangerfield,
“no respect.”
⁵
And yet, here they are, appearing as essential ingredients in our highly vaunted powers of reasoning. Of course, an excess of emotion can interfere with rational thought. We all know the feeling of having our minds freeze up when we’re nervous about speaking in public, or time-pressured during a chemistry exam. However, the link between logic and emotion is a two-way street. We’re learning that without the influence of emotions, “rational thinking” isn’t so rational after all. It’s just as likely to get us into trouble as are emotions unbalanced by thought. The take-home message of this discovery is this: just as we’ve learned that it makes no sense to consider the brain and the body as two separate things, we’re learning that our thoughts and emotions are equally bound together. They depend upon each other, and they are equally important to what we call the human mind.

It’s hard to conclude exactly what this new knowledge tells us about the mental lives of our dogs. Although dogs undoubtedly share much of the basic experience of fear, anger, happiness, and love, their emotional experiences must also be different from our own. Our thought processes are complex compared with those of dogs, and if we can’t separate our thoughts from our emotions, then we have to acknowledge that our emotions must be different from theirs, at least in some ways.

However, thanks to the tremendous strides recently made in neurobiology, we have a lot of information that we can use to look at how thoughts and emotions might combine differently in dogs and people.
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For example, you may remember, from the chapter on fear, that animals and autistic people have less active prefrontal cortexes than normal people do. Decreased activation of this area is associated with an increased ability to feel fear. That is consistent with how autistic people experience the world—they suffer more from fear and anxiety than typical people (although both groups are well acquainted with these emotions).

This finding suggests that the differences between the cognitive
abilities of dogs and people might make some of the emotions that dogs experience more intense than ours, not less. Certainly the behavior of frightened dogs supports that possibility. I’ve seen dogs so frightened they leaped out third-story windows, or emptied their bowels, bladder, and anal glands at the approach of a stranger. Everyone in animal rescue has seen dogs whose fear rendered them virtually helpless, frozen in space and unable to move even an inch. It’s not that people can’t be overcome with terror; we can. But it happens much less often in our species, perhaps because we have more power to reason than our dogs, and so there’s a higher likelihood that our emotions can be calmed by our thoughts.

Thoughts
. There’s that word again. If you want to get into an argument, start a group of people talking about whether dogs can “think.” Among scientists, philosophers, and the general public, opinions on this question are not only variable but also tend to be strongly held. However, if we’re going to talk about whether dogs can think, it’s useful to describe clearly what we’re talking about. In the next section, I discuss what thinking really is, and provide the basis for the argument that yes, dogs can think (just not like we can).

In his youth, Charlie was a bit of a roamer. The German Shepherd-Labrador mix terrified his owners by dashing out of their expansive yard and disappearing down the road. He’d come back hours later, after Joe and Bernadette were sick with worry and exhausted from canvassing the neighborhood. Finally, they got an “electronic fence” system to keep him in the yard. Charlie wore a collar that gave him a shock if he walked over a buried wire at the boundaries of the property. The higher priced systems, like Charlie’s, warn the dog with a beeping sound if he gets close to the wire
.
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If the dog ignores the beep, he receives a shock. The idea is that the dog will only have to be shocked a few times, because the beep will tell him when he’s getting too close to the boundary
.

That was the theory, anyway, but Charlie had other ideas. Charlie figured
out that if he lay down close enough to the wire to make the collar beep continuously, it eventually stopped. Once the beeping stopped, the collar couldn’t deliver a shock anymore (because the battery had run out of juice), and Charlie could saunter out of the yard
.

This story about Charlie is just that—a story. It circulated around the dog world a few years ago, and I love it because it stimulates discussion about the mental abilities of a dog. If it’s true, no one can deny that Charlie is one smart dog. What’s in question, though, is how Charlie figured out how to beat the system. Did he learn through trial and error that a continuous beep meant he couldn’t get shocked, or did he lie in the yard thinking about it, and figure it out in a moment of insight?

We all know that the mental abilities of dogs and people are profoundly different. Dogs don’t read books, design automobiles, or write sonatas. Dogs may understand a lot of words we teach them, but they don’t spontaneously begin to use a complex, symbolic language early in their development. They don’t lie in their dog beds planning what they should do on their evening walk next Thursday. Dogs are unable to solve problems that are trivial to us—think of dogs who have wound their leashes around a tree and can’t figure out how to reverse their direction to unwind the leash. Pip, the smartest dog I’ve ever had, appears to be surprised every evening, as she has been for fifteen years, when she has to back away from a gate that opens inward in order to go through it.

Granted, dogs can do amazing things—anyone who earns his living with working dogs can take center stage at a dinner party relating the remarkable things the dog has done—but the problem-solving ability of the human brain leaves even the most brilliant dogs in the dust. We share ancient brain centers like the cerebellum and the limbic system with other mammals, but the “thinking” part of our brains is radically different.

We’ve all seen countless pictures of the human brain. If you take away the skull, you find a rather undistinguished-looking gray mass, wrinkled like a big, sodden walnut with deep nooks and crannies creasing its surface. What’s most visible are the cerebral hemispheres, covered by the thin membrane called the cortex. As we saw in Chapter 2,
the cortex acts as the mind’s decision center, in both people and dogs. It’s the neurons in the cortex that help you decide when and where to throw the ball for your dog, and it’s in her cortex that your dog decides whether to bring you back the ball, or whether she should dash behind the house and hide it under the bushes. The thin but essential blanket of cells that make up the cortex is only about an eighth of an inch thick, and in humans the cerebral hemispheres beneath it are crinkled, like a wadded-up piece of paper. It’s those wrinkles that make us humans so special, because by increasing the surface area of the cerebral hemispheres, they radically increase the size of the cortex that covers them.

There’s a reason for those wrinkles. As we evolved as strategic thinkers (needing more and more neurons in the cortex) we couldn’t keep increasing the size of our brains, or babies would never make it out of the birth canal. (Most of the mothers I know think things went too far as it is.) The solution was to create more surface area for the cortex by wrinkling the surface of the hemispheres. If you smoothed out a human cortex as you would a crumpled piece of paper, it would be as large as a full-size newspaper page laid open. If you did the same to the smoother cortex of a chimpanzee, it would be a quarter of that size. A rhesus monkey’s would take up only the space of a large postcard, and your dog’s would be that size or smaller.
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This difference in structure and function creates a profound difference between us and our dogs. We know that dogs can understand a large number of words, but it’s also overwhelmingly clear that they aren’t capable of anything even approaching human language. The average high school student knows more than eighty thousand words; a dog who knows two hundred words makes the national news. Humans have specialized areas in the cortex of the brain that are critical to language; our dogs have no equivalent.

However, that doesn’t mean dogs can’t form and manipulate “mental abstractions,” which is the basis of being able to think. There’s no reason to believe that what we call thinking is something you either can or cannot do. The few studies that have been done on dogs strongly
support the hypothesis that dogs are able to conceptualize at least simple abstractions.
⁹
One researcher taught dogs to select the larger of two objects to get a food treat, regardless of the shape or composition of the object. “Larger” and “smaller” are perfect examples of conceptual abstractions—there’s no object called a “large” that you can ask your dog to fetch. Dogs can also be taught to select the item that’s “different” in size or shape in an array of three objects. That’s another example of an abstraction: you can’t see, smell, or taste a “different”—it’s a concept, which can only exist in one’s mind.