Brain-Machine Interfaces Make for Tricky Ethics

Direct connections from brains to computers may someday help free paralyzed people from the constraints of their bodies. They're already used to reverse deafness and blindness. But as they become more refined, brain-machine interfaces will almost certainly be used for non-therapeutic purposes — and with that expansion comes profound ethical questions.

"Whether these technologies are used in a way that's in harmony with — or an affront to — human dignity is the main question," said Adam Keiper, director of the Ethics and Public Policy Center's program on science, technology and society.

First-generation neuroelectronics are already on the market in the form of hearing aids — 150,000 people have straight-to-brain cochlear implants — and deep-brain stimulators are used to treat Parkinson's, epilepsy and even depression. Retinal implants to replace damaged eyes are in development, as are systems that enable paraplegics to control computers by thinking.

Though incredible, these technologies may someday seem rudimentary. Scientists predict that future implants will be made from engineered tissue and organic nanomaterials rather than metal, and allow for a literally seamless union of man and machine. Brain-machine interfaces could be used for entertainment or work; the U.S. military already wants to implant them in soldiers.

To some researchers, the ethical issues are not complicated. "These questions are similar to those surrounding antidepressants," said University of Tübingen bioethicist Jens Clausen, who writes about neuroelectronics in an essay published Wednesday in Nature. "We can look at discussions that have already taken place, and figure out what is relevant."

Clausen's essay focuses on the safety of implanted circuitry and brain system-tinkering. This, however, may be the easiest question to answer: Risks can be measured and weighed against possible benefits. Far trickier questions are posed by the potential off-label applications of futuristic brain-machine systems, just as steroids provoke a different discussion when injected to help hit home runs rather than being inhaled for asthma.

"The questions related to brain-machine interfaces get much more interesting when you turn to the matter of enhancement," said Keiper.