Refresh your driving skills and you could save on auto insurance! Take 25% off the Smart Driver online course today.
by Nissa Simon, AARP Bulletin, May 5, 2009
Scratching an annoying itch is one of life’s simple pleasures, but why it provides such profound relief has long been a mystery. Researchers are now homing in on some answers.
Antihistamines can relieve the kind of itching caused by mosquito bites or poison ivy, but scientists want to find ways to relieve the unbearable itching caused by illnesses such as cancer or liver disease. “Antihistamines don’t help most of the hundreds of conditions that can cause chronic, untreatable itch,” says neuroscientist Glenn Giesler of the University of Minnesota in Minneapolis.
Scratching, however, offers an “aah . . . ”
But why? Giesler and his colleagues found that scratching sends a signal from nerve cells in the skin to specialized nerve cells in the spinal cord, which then tell the brain to turn off the itching.
To tease out how it works, scientists sedated monkeys and injected histamine into their lower legs to produce an itch. In response, the spinal cord nerves fired electrical signals, which the scientists could hear through speakers set up in the lab. “It sounds like a Morse code of the nervous system,” Giesler says. They then scratched the leg with an instrument that simulates monkey fingers. The spinal cord nerves fell silent.
“If we can discover a way to mimic the relief that scratching provides, we could get around the destructive effect that constant scratching has on the skin,” says Yale University neurobiologist Robert LaMotte, who was not involved in the study. “This research identifies the nerve cells to target with new anti-itch drugs.”
The study was published online in the journal Nature Neuroscience on April 6.
Nissa Simon, who lives in New Haven, Conn., writes about nutrition and medical issues.
Please leave your comment below.
You must be logged in to leave a comment.
Visit the AARP state page for information about events, news and resources near you.
Featured AARP Member Benefits
See All >
You are leaving AARP.org and going to the website of our trusted provider. The provider’s terms, conditions and policies apply. Please return to AARP.org to learn more about other benefits.
Your email address is now confirmed.
You'll start receiving the latest news, benefits, events, and programs related to AARP's mission to empower people to choose how they live as they age.
You can also manage your communication preferences by updating your account at anytime. You will be asked to register or log in.
In the next 24 hours, you will receive an email to confirm your subscription to receive emails
related to AARP volunteering. Once you confirm that subscription, you will regularly
receive communications related to AARP volunteering. In the meantime, please feel free
to search for ways to make a difference in your community at