“Sure,” says Edward Boyden, Benesse Career Development Professor at the MIT Media Lab. “The brain is an electrical device. Electricity is a common language. This is what allows us to interface the brain to electronic devices.”
One way to pick up electrical brain signals involves outfitting a person with Medusa-like headgear, attaching sticky, conductive patches to the scalp and forehead and reading the electrical activity of the brain over time. This method, called electroencephalography or EEG, has been used in medicine for years.
EEGs don’t read thoughts neuron by neuron. Rather, says Boyden, they do so “collectively.” Imagine trying to eavesdrop on a group of people crowded in a room. “If the people are chanting the same thing, you can understand it,” Boyden says, “but if they’re all saying something different, it’s a noisy mess.” Luckily, neurons close together seem to pulse together, chanting out signals as a group. The frequencies of brain waves can reveal abnormal patterns that help doctors diagnose epileptic seizures, coma, or brain death.
Video games have started to use EEG technology, equipping gamers with sleek headsets that claim to read the gamer’s mind and translate their thoughts into machine-readable instructions. Gamers can use their minds to drive a virtual car, guide an avatar through Jedi lightsaber training, or create musically-inspired brain-wave art. A popular new board game game purportedly puts telekinesis to work by challenging players to use their brain waves to float a real-life ball through a series of obstacles.
Neural prosthetic devices also use the shared language of electronics to control robotic limbs, but through a somewhat more sophisticated interface with the brain. These devices use neural implants consisting of an array of electrodes that are implanted in the brain to monitor a small set of neurons and detect an individual’s intentions to maneuver an object such as a prosthetic limb. Mathematical formulas then decode these brain signals and turn them into instructions that drive the prosthetic device.
Neural prosthetics don’t yet have the kind of dexterity seen in sci-fi movies, nor do mind-reading headsets approach the exquisite control that joysticks and manual controllers provide. The reason, says Boyden, is that we don’t yet understand how the brain codes information. “We have the genome. We know the code and the structure of genes. This allows genetic engineering to be precise,” says Boyden. “That’s where the exciting work in neuroengineering over the next decade is going to be: learning to read and write the neural code.” – Elizabeth Dougherty