This is an example of how at-risk teen behavior can get the wrong kind of reinforcement online, but the Internet can also be a means of earlier detection - if parents and friends find out where on the Net a teen is getting that reinforcement. Experts say increasing numbers of teens are discussing self-injury on the Web and forming "cutting clubs" at school. The trend is "prompting many to try it who might not otherwise have known about it," the New York Times reports. "There are no exact numbers for this largely hidden problem, but anonymous surveys among college students suggest that 17% of them have self-injured, and experts estimate that self-injury is practiced by 15% of the general adolescent population." The behavior is a way of turning emotional pain on oneself and can be addictive. "Experts theorize that it may be reinforced by the release in the brain of opioidlike endorphins that result in a natural high and emotional relief," according to the Times. The support or validation found in cutting groups online or at school can also help perpetuate self-injury. Please see the article for information on detection and treatment.