Scientists are learning volumes about the brain -- how it can make split-second decisions, how it learns from past mistakes, how it converts pulses of light into a complex visual scene. But, for some, deciphering the "language" of the electrical pulses that travel through our brains is only half the story. The second part, and one that is far more philosophical and complex, is how that brain activity translates into consciousness -- a person's self-awareness and perception of the world around them.

Bill Newsome, a neuroscientist at Stanford University in Palo Alto, CA, has spent the last twenty years studying how neurons encode information and how they use it to make decisions about the world. In the 1990s, he and collaborators were able to change the way a monkey responded to its environment by sending electric jolts to certain parts of its brain. The findings gave neuroscientists enormous insight into the inner workings of the brain.

But Newsome is obsessed with a lingering question: How does consciousness arise from brain function? He feels the best way to answer that question is by implanting an electrode into his own brain -- and seeing how the electric current changes his perception of the world.

Newsome would not be the first person with a brain implant. Epilepsy patients undergo electrical stimulation prior to brain surgery. A paralyzed man in New England has an experimental implant that translates his brain activity into movements of a robotic arm. And, perhaps most famously, Kevin Warwick, a cybernetics professor at the University of Reading, U.K., first implanted a chip into nerve fibers in his arm in 2002, then implanted a chip in his wife's arm, as part of his quest to become a cyborg.

It's not certain that Newsome will get approval for such a radical undertaking. But, if he does, his experiment won't be in the interest of curing a disease or become a human machine. He's hoping to do something broader: understand consciousness.

Technology Review: Why is understanding consciousness so important to you?

Bill Newsome: I think that how consciousness arises out of brain function is one of the most fascinating and important questions in all of neurobiology. If we understand the system completely (from input to output) at a cellular level, but still do not know exactly what causes conscious mental phenomena, we will have failed.