Inside of a Dog_ What Dogs See, Smell, and Know - Alexandra Horowitz [59]
These behaviors reflect the infant's burgeoning understanding that other people have attention, attention that can light on objects of interest: a bottle, a toy, or them. Between twelve and eighteen months, they begin to engage in bouts of joint attention with others: locking eyes, then looking to another object, then back to eye contact. This marks a breakthrough: to achieve full "jointness" the infant must on some level understand that not only are they both looking together, they are attending together. They are understanding that there is some invisible but real connection between other people and the objects that are in their line of vision. Once they do this, all hell can break loose. Infants can start manipulating others' attention simply by gazing someplace. They check where other people are looking and pointing, and they begin to notice if adults are looking at them while they are doing activities they want to share (or conceal). They will give an anticipatory glance at an adult before pointing or showing themselves. They work very hard to get attention looking at them. And they may begin avoiding attention: going out of a room at key moments, or concealing objects from an adult's view. (This prepares them well for being difficult adolescents.)
We all become characteristically human by this same developmental route. Within a few years an infant goes from aimlessly looking out of new eyes, to looking meaningfully, to gazing at others, to following the gaze of others. They happily hold eye contact. Before long they are using gaze to get information, to manipulate the gaze of others—by distraction, gaze avoidance, or pointing—and to get attention. At some point, they come to a realization about the fact of the mind behind someone else's gaze.
THE ATTENTION OF ANIMALS
She comes within an inch of me and starts panting at me, eyes wide and unblinking, to tell me that she needs something.
Step-by-step, cognition researchers have been tracing this developmental course with a new subject: non-human animals. How much of the infant's trajectory is followed by animals? After they open their eyes, do they look with intention? Do they notice others' eyes? Do they understand the importance of attention?
This is one facet of the study of animal cognition, which asks what an animal subject understands about the "mental states" of others. Most of the experimental tests run with animals are of the kind we feel sure we humans excel at: tests of physical and social cognition. Captive animals from sea slugs to pigeons to prairie dogs to chimpanzees have been set into mazes; presented with counting, categorizing, and naming tasks; asked to discriminate, learn, and remember series of numbers and pictures. Tasks are devised to see if they recognize, imitate, or deceive others—or even recognize themselves. And in some tests, the question is even more characteristically human: of the kind of social thinking going on when animals interact—with members of their own species, and with those of other species. When a caged chimpanzee looks at a human attendant, is he considering anything about the attendant? Does he wonder how to get her to open the door (does he wonder anything at all?), or is he simply waiting to see what this colorful, animate object nearby does that might be relevant or interesting? Does a cat consider that mouse as an agent, as an animal with a life—or does he see the mouse as a moving meal that must be stopped and dismantled?
As we've touched on already, the subjective experience of animals is notoriously difficult to get at scientifically. No animal can be asked to relate its experience in voice or on paper,* so behavior must be our guide. Behavior has its pitfalls, too, since we cannot be positive that any two individuals' similar behavior indicates similar psychological states. For instance, I smile