Despite much research on pain receptors, investigators have only recently focused on itch and how the body distinguishes between itch and pain. This research, including new findings by UC Berkeley's Diana Bautista, show that the receptors responding to irritants actually work by triggering pain receptors, which in turn send signals to the brain that make us want to scratch. The connection suggests that new pain relievers under development may also help relieve intractable itch.

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