You might as well be feeding your children ground glass, a Utah educator says.

"Letting your children watch violence on television is like feeding the ground glass," Victor Cline, a therapist and professor, said Thursday night. "If you are what you eat, your mental diet is just as important as your nutritional one."The University of Utah professor spoke to parents who attended the Orem Council PTA seminar on critical issues.

"The amount of violence a child sees at 7 predicts how violent he will be at 17, 27 and 37," he said. "Children's minds are like banks - whatever you put in, you get back 10 years later with interest."

Cline said violent television can change children in two ways. It teaches them - step-by-step - how to commit violent acts, and it desensitizes them to the horror of such behavior and to the feelings of victims.

He told stories of children who had hanged themselves or set people on fire after seeing similar acts on television. He also discusses his testing of two groups of children. Half had been "saturated" with television violence and half had watched little television in their lives.

"We showed them a `Rocky' movie with no violent crime, but lots of aggressive behavior in the boxing. The children who had watched lots of television were bored, but the ones who hadn't were emotionally aroused. Their hearts beat wildly, but their peers who had been desensitized didn't react at all."

Cline said America is having "an explosion of interpersonal violence like we have never seen before." There are more murders annually in Manhattan, N.Y., than in all of the United Kingdom, he said. "The violence is because of violence in our entertainment."

Pornography works on the same principles, he said.

"Most pornography dehumanizes females. Women sense the hostility toward women, so they don't like pornography."

Men who view pornography are changed, he said, and may see women as objects to be used and discarded.

"There is no way you can look at it (pornography) and look at it and look at it without accepting some of the ideas."

Cline said people are vulnerable to media, but they have strengths too. People can decide to take responsibility for their lives. Therapy can help those unable to make changes alone. Parents who want their children to watch less television can set limits. And people who are upset with the sex and violence in current programming can lobby for changes.

Citizens should make their views known to network officials and programmers at local television stations, he said. He acknowledged that such officials often blame the marketplace, saying there is violence on television because that's what most people want. The few who don't want to watch it can turn their sets off.

Cline said that argument did not address "the addictive nature" of television. He also likened such programmers' response to "permitting people to buy orange juice laced with rat poison and saying people who don't want it don't have to buy it."