Body-mod artists — body-piercers — have developed A Sixth Sense for a Wired World:
What if, seconds before your laptop began stalling, you could feel the hard drive spin up under the load? Or you could tell if an electrical cord was live before you touched it? For the few people who have rare earth magnets implanted in their fingers, these are among the reported effects — a finger that feels electromagnetic fields along with the normal sense of touch.
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Body-mod artists Jesse Jarrell and Steve Haworth’s original idea was to implant a magnet to carry metal gadgets. It turns out that doesn’t work: If you try to carry something magnetic on your implant regularly, the pinched skin between the magnets dies and your body rejects the implant. But they came up with a new application when a mutual friend suffered an accident that left a shard of iron in his finger. He worked with audio equipment, and found that he could tell which speakers were magnetized from the sensation that passed through his finger at close range.
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According to Huffman, the magnet works by moving very slightly, or with a noticeable oscillation, in response to EM fields. This stimulates the somatosensory receptors in the fingertip, the same nerves that are responsible for perceiving pressure, temperature and pain. Huffman and other recipients found they could locate electric stovetops and motors, and pick out live electrical cables. Appliance cords in the United States give off a 60-Hz field, a sensation with which Huffman has become intimately familiar. “It is a light, rapid buzz,” he says.