Scratching an itch can bring a contradictory wave of pleasure and misery. A mouse study on scratching, reported in the Jan. 31 Science, fleshes out this

Studies show that scratching overrides itch signals and engages pain-modulating regions in the brain, creating a sense of relief and calm

The TRPV4 protein’s dual nature, found in studies with mice, may complicate the hunt for human itch treatments