Closing the Loop
The Human-Machine Interface and the Race to Turn Thought into Motion
The griddle overheats, and a skittering of hot oil pops from pan to skin. The combined sensation of heat and pain trigger a natural reaction; I jerk my hand away, and instinctively put the offended knuckle in my mouth. Two and half seconds, maybe less, but thousands of firing neurons: Hot, a sensation I feel, and which must be embodied to be understood; Pain, the brain’s interpretation of tissue damage, from my hand to my neurons and back; jerk, an involuntary motion, faster than conscious thought, and my ability to locate the part of my face most likely to put out the sting without missing (or jabbing myself in the eye). To feel, to know our body in space, and to make use of our limbs — we take these tiny actions for granted when they function, when we are whole and mobile. But what happens when we lose the pieces of ourselves?
The history of prosthetic limbs reaches almost as far back as the history of amputation: An Egyptian queen wore a false golden eye; a Roman soldier wore an arm fashioned from metal; sixteenth-century surgeon Ambroise Paré fashioned hands with articulated digits. Humankind has long known how to replicate the look of missing limbs — but the function remained a distant dream. But what if the mind could control these external replacement parts…