Itch. Past studies have shown that whatever the cause—perhaps just hearing me talk about itch—something triggers nerve fibers that send a signal lighting up three areas of the brain: the emotional regions; the limbic system that sparks the urge to scratch; and the cortex that tells you where to scratch.

And recently researchers discovered that where the itch begins can predict how bad it is—and how much pleasure you’ll get by scratching it. The study is in the British Journal of Dermatology.

The researchers induced an itch on the ankles, forearms and backs of 18 subjects. And the research team also relieved the itch in a uniform way with a scratching device, rather than let each subject go to town in different and unmeasureable ways.

The results: The experimentally induced itch was particularly bad on the back and ankle. And scratching the back got rid of the itch most effectively. But scratching the ankle provided the most pleasurable relief.

So not all itches are created equal, even if they’re induced equally. The next steps are to find out why, and whether there is a treatment that can match the pleasure of the scratch.

—Christie Nicholson

[The above text is a transcript of this podcast.]