Researchers have uncovered a neural signal involving the TRPV4 molecule that tells the brain when scratching an itch has provided enough relief. Experiments in mice showed that without this signal, scratching episodes become prolonged even as overall frequency drops.
The discovery comes from studies led by Roberta Gualdani at the University of Louvain in Brussels. Her team found that TRPV4 channels in sensory neurons help activate a negative feedback mechanism in the nervous system. This mechanism informs the spinal cord and brain that scratching has delivered satisfaction, prompting the behavior to stop.
