MIAMI — If you have an itch you just can’t seem to scratch away, a new study has some helpful advice: rub, don’t scratch! Research just published by the Society for Neuroscience finds that rubbing one’s skin activates an “anti-itch pathway” within the spinal cord. So, not only is rubbing better for your skin, it’s also a more efficient way of attaining elusive itch relief.
The natural first reaction to an itch is to immediately start scratching. But, scratching can be quite harmful to the skin, and especially damaging for sensitive bodily areas. All that, combined with these new findings, make a compelling argument to stop scratching altogether.
The research team came to their conclusions after performing a series of experiments using lab mice.
How were they able to incite itchiness in the group of rodents? An “itch-inducing chemical” was placed underneath their skin. After that, researchers observed and recorded how the dorsal horn neurons within the rodents’ spinal cords reacted to their paws being rubbed.
As their paws were being stroked, the mice’s neurons fired more often, and then less often when the stroking stopped. However, those neurons respond to both touch and itch, so that increased activity during stroking was only due to the added touch. The decrease in activity, though, did in fact correlate with itch relief.
Now, the very same decrease in neural firing activity was also observed when the research team directly stimulated the touch-sensing neurons under the rodents‘ skin. In other words, the dorsal horn neurons also stopped firing when researchers started rubbing the itchy parts of the rodents’ bodies.
When the study’s authors deactivated the sensory neurons (and a subtype of anti-itch interneurons), it didn’t result in any less scratching from the mice or a decrease in dorsal horn neuron firing. When those neurons are activated, on the other hand, rubbing seems to provide the mice with itch relief.
All in all, the research team behind this project believe their work strongly suggests that rubbing an itch sets off a series of neuronal events, ultimately resulting in itch relief. First, sensory neurons under the skin are activated. In turn, those neurons stimulate anti-itch interneurons in the spinal cord, which spark reduced dorsal horn neural activity.
The study is published in the Journal of Neuroscience.