Worlds of Feeling; December 2004; Scientific American Mind; by Martin Grunwald; 6 Page(s)

At dawn the beeping of your alarm clock drills relentlessly into your consciousness. With eyes still closed, you reach for the nightstand. Your hand glides over your bedtime book, reading glasses and the cup of water, landing almost precisely on the noisy nuisance. After a short fumble, your fingers press down on a raised button to silence the alarm. With a sigh, you sink back into sleep. You do not dwell on what an impressive feat you have just performed. The sense of touch--which is absolutely necessary for us to perform our physical capabilities as well as for learning--is not something we waste time thinking about.

Perhaps that is because life without the ability to feel is scarcely imaginable. The complete absence of this sense never occurs in nature, and independent life would not be possible without it. Beyond giving us the ability to smack a blaring alarm clock, the luxurious provision of sensors on our hands, for instance, permits us to achieve quite a lot even with our eyes closed. Consider the seemingly simple act of writing with a ballpoint. This task demands a constant flow of detailed information from sensors to the brain, which report how our fingers are holding the pen and measure pressure changes on the skin and joints.