Are We Smart Enough to Know How Smart Animals Are?(36)
While we waited, the dogs played nicely together in the room, but when it turned into a fight in which Eli drew a drop of blood, we had to separate them. This was surely different from most human waiting rooms. For Callie, it was the eighth time she had received the muttmuffs, or foam-filled ear seals that fit like headphones over a dog’s head to reduce sound, such as the buzzing of the magnet. It is an important part of the project to get the dogs used to odd noises. Strangely enough, Greg was convinced that this might work after seeing a video of the raid on Osama bin Laden’s compound. SEAL Team 6 had a trained dog jump out of a helicopter with an oxygen mask on while strapped to a soldier’s chest. If you can train dogs to do this, Greg thought, we certainly should be able to get them used to the magnet’s noises. This, together with training them to put their heads in a chinrest, is the secret to the project’s success. With lots of little chunks of hotdog, the canines are trained at home so that the chinrest in the magnet is familiar to them and they know what is expected of them.38
Callie in a magnetic resonance scanner. Dogs can be trained to sit still, which permits the study of their cognition through brain imaging, such as fMRI.
The frequent rewards pose a bit of a problem, because eating requires jaw movements, which interfere with brain imaging. Via a special dog ladder, Callie ran into the scanner and took her position waiting for the procedure. She was a bit too excited, though, because her tail wagged wildly, adding another source of body movement. Greg’s joking that we were looking for the tail-wagging area in the brain was not too far off. Eli needed a bit more encouragement to enter the scanner but was convinced once he saw his familiar chinrest. His owner told me that he is so used to it, and associates it with such good times, that she sometimes finds him sleeping at home with his head inside. He remained still for three minutes, long enough for some good scanning.
Pretrained hand signals tell the dog in the scanner whether a treat is forthcoming. This is how Greg studies activation of their pleasure centers. His goals are rather modest at this point, such as to show that similar cognitive processes in humans and dogs engage similar brain areas. Greg is finding that the prospect of food activates the caudate nucleus in the canine brain in the same way that it does in the brain of businessmen anticipating a monetary bonus.39 That all mammalian brains operate in essentially the same way has also been found in other domains. Behind these similarities is a much deeper message, of course. Instead of treating mental processes as a black box, as Skinner and his followers had done, we are now prying open the box to reveal a wealth of neural homologies. These show a shared evolutionary background to mental processes and offer a powerful argument against human-animal dualism.
Although this research is still in its infancy, it promises a noninvasive neuroscience of animal cognition and emotion. I felt as if I were at the threshold of a new era, while Eli trotted out of the scanner to lean his head on my knee and let out a deep dog sigh to signal his relief that all had ended well.
5 THE MEASURE OF ALL THINGS
Ayumu had no time for me while he was working on his computer. He lives with other chimps in an outdoor area at the Primate Research Institute (PRI) of Kyoto University. At any moment, an ape can run into one of several cubicles—like little phone booths—equipped with a computer. The chimp can also leave the cubicle whenever he wants. This way playing computer games is entirely up to them, which guarantees sound motivation. Since the cubicles are transparent and low, I could lean on one to look over Ayumu’s shoulder. I watched his incredibly rapid decision making the way I admire my students typing ten times faster than me.
Ayumu, is a young male who, in 2007, put human memory to shame. Trained on a touchscreen, he can recall a series of numbers from 1 through 9 and tap them in the right order, even though the numbers appear randomly on the screen and are replaced by white squares as soon as he starts tapping. Having memorized the numbers, Ayumu touches the squares in the correct order. Reducing the amount of time the numbers flash on the screen doesn’t seem to matter to Ayumu, even though humans become less accurate the shorter the time interval. Trying the task myself, I was unable to keep track of more than five numbers after staring at the screen for many seconds, while Ayumu can do the same after seeing the numbers for just 210 milliseconds. This is one-fifth of a second, literally the bat of an eye. One follow-up study managed to train humans up to Ayumu’s level with five numbers, but the ape remembers up to nine with 80 percent accuracy, something no human has managed so far.1 Taking on a British memory champion known for his ability to memorize an entire stack of cards, Ayumu emerged the “chimpion.”
Ayumu’s photographic memory allows him to quickly tap a series of numbers on a touchscreen in the right order, even though the numbers disappear in the blink of an eye. That humans cannot keep up with this young ape has upset some psychologists.
The distress Ayumu’s photographic memory caused in the scientific community was of the same order as when, half a century ago, DNA studies revealed that humans barely differ enough from bonobos and chimpanzees to deserve their own genus. It is only for historical reasons that taxonomists have let us keep the Homo genus all to ourselves. The DNA comparison caused hand-wringing in anthropology departments, where until then skulls and bones had ruled supremely as the gauge of relatedness. To determine what is important in a skeleton takes judgment, though, which allows the subjective coloring of traits that we deem crucial. We make a big deal of our bipedal locomotion, for example, while ignoring the many animals, from chickens to hopping kangaroos, that move the same way. At some savanna sites, bonobos walk entire distances upright through tall grass, making confident strides like humans.2 Bipedalism is really not as special as it has been made out to be. The good thing about DNA is that it is immune to prejudice, making it a more objective measure.