That Irritating Itch? It May Just Be Your Brain

In fact, our noodles could be inventing 90% of what we call real
By Harry Kimball,  Newser Staff
Posted Jun 24, 2008 3:17 PM CDT
Afghan shepherd Sardar Ahmad recovers in a hospital after doctors amputated his feet and one hand due to effects of cold.   (AP Photo)
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(Newser) – A woman suffers from an itch so severe that she scratches right through to her brain—yet doctors find no medical ailment. War victims feel the sensations of a real limb—but from phantom appendages. What does it all add up to? Perhaps a new understanding of how our brains perceive reality: Call it the “brain’s best guess” theory, Atul Gawande writes in the New Yorker.

Emerging brain theory concludes that 90% of perceptions originate inside the brain, including neurological problems once considered nerve-related. As for the outside world, brains just rounds up weak sensory signals and call them experience. "Perception is the brain’s best guess about what is happening in the outside world," Gawande notes. "Perception," in short, "is inference."