The high derived from cocaine use is interpreted by the brain as a reward, according to new research by scientists at McGill University in Montreal. They studied 10 non-addicted drug users who alternated between sniffing cocaine and a placebo powder and found their brains secreted dopamine, a chemical that is like a reward-response. The more coke that a participant had taken in the past, the more his brain secreted dopamine. The researchers say that this information may help in developing treatment against drug addiction.