efforts of those who hope to build electrode arrays to record simultaneously from hundreds. But by now we should be used to seeing problems solved that only yesterday seemed insuperable.
Running counter to wooly ideas about constellations of cells is long-standing and still accumulating evidence for the existence of cortical regions specialized for face perception. Charles Gross's group at'Princeton has recorded from cells in the monkey, in a visual area of the temporal lobe, that seem to respond selectively to faces. And humans with strokes in one particular part of the . inferior occipital lobe often lose the ability to recognize faces, even those of close relatives. Antonio Damasio, at the University of Iowa, has suggested that these patients have lost the ability to distinguish not just faces but a I broader class of objects that includes faces. He describes a woman who could recognize neither faces nor individual cars. She could tell a car from a truck, , but to find her own car in a parking lot she had to walk along reading off the license plate numbers, which suggests that her vision and her ability to read numbers were both intact.
Speculating can be fun, but when can we hope to have answers to some of these questions about perception? Some thirty-seven years have passed since Kuffler worked out the properties of retinal ganglion cells. In the interval the way we view both the complexity of the visual pathway and the range of problems posed by perception has radically changed. We realize that discoveries such as center-surround receptive fields and orientation selectivity represent merely two steps in unraveling a puzzle that contains hundreds of such steps. The brain has many tasks to perform, even in vision, and millions of years of evolution have produced solutions of great ingenuity. With hard work we may come to understand any small subset of these, but it seems unlikely that we will be able to tackle them all. It would be just as unrealistic to suppose that we could ever understand the intricate workings of each of the millions of proteins floating around in our bodies. Philosophically, however, it is important to have at least a few examples—of neural circuits or proteins—that we do understand well: our ability to unravel even a few of the processes responsible for life—or for perception, thought, or emotions—tells us that total understanding is in principle possible, that we do not need to appeal to mystical life forces—or to the mind.
Some may fear that such a materialistic outlook, which regards the brain as a kind of super machine, will take the magic out of life and deprive us of all spiritual values. This is about the same as fearing that a knowledge of human anatomy will prevent us from admiring the human form. Art students and medical students know that the opposite is true. The problem is with the words: if machine implies something with rivets and ratchets and gears, that does sound unromantic. But by machine I mean any object that does tasks in a way that is consonant with the laws of physics, an object that we can ultimately understand in the same way we understand a printing press. I believe the brain is such an object.
Do we need to worry about possible dire consequences of understanding the brain, analogous to the consequences of understanding the atom? Do we have to worry about the CIA reading or controlling our thoughts? I see no cause for loss of sleep, at least not for the next century or so. It should be obvious from all the preceding chapters of this book that reading or directing thoughts by neurophysiological means is about as feasible as a weekend trip to the Andromeda galaxy and back. But even if thought control turns out to be possible in principle, the prevention or cure of millions of schizophrenics should be easy by comparison. I would prefer to take the gamble, and continue to do research.
We may soon have to face a different kind of problem: that of reconciling some of our most cherished and deep-seated beliefs with new knowledge of the brain. In 1983, the Church of Rome formally indicated its acceptance of the physics and cosmology Gallileo had promulgated 350 years earlier. Today our courts, politicians, and publishers are struggling with the same problem in teaching school children the, facts about evolution and molecular biology. If mind and soul are to neurobiology what sky and heaven are to astronomy and The Creation is to biology, then a third revolution in thought may be in the offing. We should not, however, smugly regard these as struggles between scientific wisdom and religious ignorance. If humans tend to cherish certain beliefs, it is only reasonable to suppose that our brains have evolved so as to favor that tendency—for reasons concerned with survival. To dismantle old beliefs or myths and replace them with scientific modes of thought should not and probably cannot be done hastily or by decree. But it seems to me that we will, in the end, have to modify our beliefs to make room for facts that our brains have enabled us to establish by experiment and deduction: the world is round; it goes around the sun; living things evolve; life can be explained in terms of fantastically complex molecules; and thought may some day be explained in terms of fantastically complex sets of neural connections.
The potential gains in understanding the brain include more than the cure and prevention of neurologic and psychiatric diseases. They go well beyond that, to fields like education. In educating, we are trying to influence the brain:
how could we fail to teach better, if we understood the thing we are trying to influence? Possible gains extend even to art, music, athletics, and social relationships. Everything we do depends on our brains.
Having said all this, I must admit that what most strongly motivates me, and I think most of my colleagues, is sheer curiosity over the workings of the most complicated structure known.