Ah! Why we scratch an itch

I'm not really sure they really know exactly, but they have more of an idea what is happening in the brain, by comparing results from MRI scans.

clipped from www.abc.net.au Julie Steenhuysen Oh, it brings such blessed relief and now scientists can tell you why. Scratching an itch temporarily shuts off areas in the brain linked with unpleasant feelings and memories. "Our study shows for the first time how scratching may relieve itch," says Dr Gil Yosipovitch, a US dermatologist at Wake Forest University Baptist Medical Center in North Carolina. studies show that pain, including vigorous scratching, inhibit the need to itch Yosipovitch and colleagues looked at what goes on in the brain when a person is scratched, publishing their results online in the Journal of Investigative Dermatology He and colleagues used a technique known as functional magnetic resonance imaging to see which areas of the brain are active during scratching. Scratching reduced activity in the anterior cingulate cortex and the posterior cingulate cortex, areas linked with pain aversion and memory. the more intensely a person was scratched, the less activity they found in these areas of the brain