痒感多由蚊虫叮咬、过敏等引发的局部炎症产生，通过细直径慢神经元经脊髓丘脑束传导至大脑。而皮肤中的机械感受器能感知触摸和震动，其信号通过粗直径快神经元经背柱传导。脊髓内两类神经元通过中间神经元交联，触摸信号会激活抑制痒感传导的神经元，这就是 “闸门理论”—— 触摸能 “关闭” 痒感通道。此外，触摸刺激大脑深层结构会反向抑制痒感传递，功能性磁共振成像研究还显示，挠痒能激活大脑奖励中枢，带来愉悦感。

Despite the saying “happiness is having a scratch for every itch,” itching often makes the itchy skin condition worse. So why is the instinct so strong? In a study with mice, researchers from the ...

When you’ve got dry, itchy skin during the winter, nothing beats a good scratch. But what exactly is going on in your body when you scratch an itch that makes it feel so darn satisfying? First, know ...

What’s common between a scratchy sweater, a mosquito bite, and poison ivy? A brush with any of them guarantees an itchy spot on the skin. Scratching that itch is extremely tempting because of how ...

It can be a relief to scratch the occasional itch, but when itch gets out of control, it can become a serious health problem. How does the body know when to stop? Scientists at UC San Francisco are ...

One of the greatest pleasures in life is to scratch an itch — in both the real and figurative sense. Although scratching an itch provides immediate (albeit temporary) relief, it may actually trigger ...

I remember it well: our dark winter of itch when the kids were small. It started with a note sent home—years before the pandemic—that my child had been exposed, not to a deadly virus but to lice.

MINNEAPOLIS — As winter finally makes its presence felt, so does a symptom of the frigid air. Dry skin is forming and many of you might treat it in a painful, yet relieving way. Why does dry skin itch ...