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Brain Implants

We may undergo plastic surgery for silly reasons, but anyone who has a brain would think twice before tampering with the body’s physical core.

I had just finished giving a talk on the Information Revolution when a young man approached me and said: “What I really want is a brain implant so that I can move massive amounts of information rapidly and painlessly in and out of my head.” “You mean so that you can download and upload information without going through the slow eyeball, mouth and ear interfaces?” I countered. “Yes. Isn’t that a great idea?” he replied, much encouraged by my reaction. “No. It’s a lousy idea,” I said, “…unless you are talking about sensor or effector chips,” and went on to explain.

If you cannot hear because of inner-ear damage, but your auditory nerve is sound, then a cochlear implant may restore your hearing, as it has for thousands of people who underwent the two-hour procedure: A small receiver is placed within the bone behind the ear, with its two dozen electrodes surgically implanted into the cochlea, where they can electrically stimulate the auditory nerve. An external device, worn behind the ear, picks up sounds, converts them to electrical signals, and conveys them through a tiny transmitter to the implant and hence the cochlea. The auditory nerve then carries these stimuli to the brain where they are perceived as sounds. The same principle applies to people with a deficient retina and a healthy optic nerve. But because vision is more complex than hearing, the precursors to retinal implants are only now being tried on a few human beings. Sensory implants like these that help people recover a lost sense are a great idea.

Working in the other direction is also feasible: We can embed a chip in a muscle to detect the electrical signals our brain uses to flex that muscle. We can then transmit this information to a machine that will open a door or steer a wheel-chair, whenever we tighten that muscle. Some people have even been able to do simple on-off tasks like these by altering, somehow, their own brain waves, which are detected noninvasively. Such effector implants and approaches can help people gain or augment motor functions, and are also a great idea.

If sensor and effector implants are so great, why not extend them to the brain, as my young listener craves, and perform even more spectacular feats? Every night, while asleep, you could be downloading into your own human memory entire sections of the Encyclopedia Britannica. Or, you could connect your brain chip to mine, so that we could intercommunicate our thoughts, directly and rapidly.

One good reason for not doing these feats is our ignorance. While we are able to channel simple electrical signals into and out of our body for sensor and effector functions, we don’t know how to do so for more complex cognitive tasks: Where and how, within your brain, might a surgeon connect a chip’s tentacles to communicate a concept like “freedom”? While scientists have been steadily gaining new knowledge about the brain, they are far from knowing how concepts are represented in it and how we might begin tapping them.

But let’s be optimistic, and suppose that after a while we do crack this mystery and manage to connect chips to our brains so as to communicate our deepest thoughts. Wouldn’t that make brain implants a great idea? No!

Imagine that you and I and a couple of other people are successfully interconnected via brain chips. We might look cool with sockets and plugs adorning our heads. But we wouldn’t be able to start or sustain a single thought: Everybody else’s thoughts would be distracting us, screaming for attention within our heads. We might then realize that in spite of our knee-jerk craving for rapid intercommunication, some isolation among organisms is essential if they are to form a viable society. In humans, this balance between isolation and intercommunication is maintained by our seeing, hearing, speaking and gesturing activities, whose slow intercommunication speed, compared to thinking, most likely represents the best evolution could do to simultaneously preserve the individual and society.

Not yet convinced brain implants are a lousy idea? Let’s talk about the threshold people may be willing to cross before violating the sanctity of their body: While some may undergo plastic surgery for casual, even silly, reasons, everyone considering a pacemaker implant or a heart transplant is sure to proceed cautiously-and only if life depends on it. It seems that we may disturb our outer surface for less than life-and-death reasons. Not so when it comes to the heart. But, heart and brain are equally central to our being. So, why would anyone implant a chip into his brain, for less than life-and-death reasons-like downloading information? I don’t think anyone would. Not even my young listener, if he were actually facing a neurosurgeon’s drill! We have wisely set a high threshold for tampering with the core of our being, because of fear, but also because of natural, moral and spiritual beliefs. Whatever our reasons for respecting the sanctity of our body’s innermost core, they spell out, one more time, that…brain implants are a lousy idea!

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