Why does scratching relieve an itch? Often, when there is an itch, we scratch the skin, even though we know that scratching is likely to aggravate the problem. But a recent study shows that scratching reduces the sensations of pain sent to the brain. Earlier studies suggested that a specific part of the spinal cord, called the spinothalmic tract, played a key role in the way we deal with itchiness. Recent scientific study has found that primates scratching the spinothalmic tract prevented the spinal cord from transmitting signals of itchiness to the brain.