In a San Francisco operating room, a sterilized saw circles the skull. The bone casing is removed, revealing the brain, pulsating beneath a pitiable slurry of blood. The patient is awake, with no protection for his three pounds of poorly differentiated gray matter. It is both breathtaking and absurd that these constellations of folded nerves, these gooey lumps, guide the organs, process vision, and convey the self.

Robert Knight, professor of psychology and neuroscience at Berkeley's Helen Willis Neuroscience Institute

Before surgeons remove the patient’s tumor, Robert T. Knight’s students place a grid of electrodes directly on the brain tissue–to conduct a language experiment. Knight, a professor of psychology and neuroscience who heads Berkeley’s Helen Wills Neuroscience Institute, later reviews a film of this hybrid research and surgery at UCSF on his laptop computer. Even after years of study, he says, watching the brain is still “the real film noir.” He admires the brute realism of the exposed brain. Even more fascinating is the strange information discerned by the electrodes.

For decades, researchers have placed electrodes on the skull, but technology’s march toward miniaturization has now enabled Knight to set his delicate crosshatch of electrodes directly on the brain. During the language experiment, the patient reacts to a spoken noun (ball) by saying a verb (throw), and the computer represents a 12-millisecond segment of the interior cosmic symphony. “We measure the blood flow while the patient talks, looking to extract word meaning,” Knight explains. The flows register in different colors on the computer screen. Enunciation of the word ball elicits first a red rush of energy in a region devoted to auditory processing, which in turn fires the nearby language center for verbs. In tune, the verb area registers a cold blue–perhaps giving energy to the noun, perhaps somehow preparing its own effort. There are flashes of yellow and then red as the patient talks. A motor area awakens briefly as the patient’s mouth shapes the word, before the auditory region registers the speech in a brief, pale-red coda.

We are what our brains make us, and we have learned that we make our brains, too. Pianists grow an enlarged motor cortex, different from that of violinists. Bird watchers recruit the brain’s “fusiform face area”–the place where you recognize Mom–to identify avians. So do car buffs esteeming, say, the Corvette, and there are stories of amputees whose facial neurons hijack those devoted to their missing limb. No other organ demands understanding, continual theorizing, and experimentation the way the brain does–you would not ask the liver to explain itself, nor the foot to contemplate running–and in this, the golden age of brain research, the rules are still being discerned.

Our brains seem to thrive on both rule-making, which forms the basis of patterns and abstraction, and the rule-breaking work of metaphor and conceptual breakthrough. Metaphors also matter in making sense of new data: Researchers employ a metaphor in describing the “hierarchy” of nerves and networks in the brain–partly to attach the new information to what we already know of our world. Metaphors are a relation of known things to the novel and the nearly unthinkable. In a way, they are mistakes of fact–flesh is not really grass, the prophet Isaiah to the contrary–that deliver deeper truths.

The smallest and most ordinary thing, a man imagining a game of catch amid his brain’s innumerable tasks, was unseen until a few years ago. Now, it’s part of an elaborate mystery. We have entered the second generation of contemporary neuroscience. In the first generation, we mapped parts of the brain by function. Now we must understand the meaning of interactions among the parts, the way they use each other and time to function as a whole. This network of interactions, many researchers believe, is in some way responsible for our consciousness.

page 1 | 4