How scratching can stop an itch
Scientists have shown scratching helps relieve an itch as it blocks activity in some spinal cord nerve cells that transmit the sensation to the brain.
However, the effect only seems to occur during itchiness itself - scratching at other times makes no difference.
While it is widely-known scratching relieves an itch, the physiological mechanisms for how this works are little understood.
The University of Minnesota study appears in Nature Neuroscience.
http://news.bbc.co.uk/2/hi/health/7976606.stm
