Cyborgs are familiar figures in science fiction. The term was coined in 1960 meaning "cybernetic organism", a living being who was a fusion of biological and computer parts. If you think we might eventually have cyborgs in the future, you are wrong; cyborgs walk among us now, and one has written an autobiography. In _Rebuilt: How Becoming Part Computer Made Me More Human_ (Houghton Mifflin), Michael Chorost has described how an implanted computer has taken over his hearing and brought him better back to the world. It is a strange story; in one sense, it isn't unique because thousands of cochlear implants are in use now, but Chorost has a lifetime of deafness, a longstanding interest in computers, a background in literature, and a fine sense of humor that bring the story forward in a unique way.
Chorost had had impaired hearing since childhood, and it gave out entirely in 2001 when he was 36 years old. Because it was a problem within his inner ear and his auditory nerves themselves were intact, he was a candidate to get a cochlear implant. It is not a simple amplifier like a hearing aid is, but a direct stimulator of the nerves that go from the cochlea to the brain. He was distressed when it finally was turned on. "Everything sounds awful," he reports. There was a roaring sound, and everything else was muddy and incomprehensible. It got much better, and in strange ways that raise fascinating questions about sensation. For instance, the electrode array cannot stimulate the cochlea in the way it was used to, and there is a problem of frequency mismatch. A user perceives that the entire auditory spectrum is shifted into high; that was one reason that Chorost couldn't, that first day, tell a woman's voice from a man's. His own voice sounded too high, too. But the problem was resolved in a day. It was not by any tinkering with the processor or implanted devices. His own brain very quickly sensed the change, sensed that something was not normal, and unconsciously shifted itself back into the normal direction. "I _knew_ what my own voice was supposed to sound like, and by God, my brain was going to hear it that way; to hell with whatever nerves were actually being stimulated." He reflects on questions pondered 250 years ago by David Hume; reality may be out there, but the senses do not tell us about real reality, only their interpretations of it. Chorost is a living experiment that Hume would have loved.
Chorost understood that his sensation was provisional; indeed, the implant is designed to be able to take advantage of better processors as they come along. He feels this made him a better human: "The very provisionality of my perception reminded me that my political perspective was provisional also, and that it was my task as a human being to strive to connect ever more complexly and deeply with the people and places of my life." Rebuilt is not a technical introduction to new auditory gadgetry, or not just that, anyway, although at one point Chorost looked at a print-out of the program that manages the electrodes, and realized with wonder, "I was reading my own software." Chorost also has important reflections from his unique perspective about the resistance to implants (currently decreasing) within the deaf community, and the differences between humans, robots, and cyborgs, especially as the last two are depicted in film and fiction. More important, it is about how new perceptions of his cyborg self led to new interactions with people, and it is an extraordinarily personal document; there are hilarious remarks, for instance, about what to do with the gadgets and wires if you want to hear what is going on during lovemaking. It is at its best as a coming-of-age story set within technological innovation, and is fascinating on every page.
