The volume and intensity of the music at last-week's deadly AC/DC concert may have played a part in the tragedy, mesmerizing thousands of youths who may have responded to the gestures of band members and started rushing the stage.

Kenneth McKenna, a Reno, Nev., attorney who tried unsuccessfully last year to convince a judge that subliminal messages on a Judas Priest album led to the suicides of two young men, said Monday he believes heavy metal music induces violent behavior."Surging at a concert really is the responsibility of the band," he said. "The band needs to show some kind of restraint. AC/DC is a heavy-metal, head-banging kind of band. This kind of behavior certainly is not surprising."

McKenna said one theory is that the music at such a concert becomes so loud it causes pain in the ears. The brain responds by releasing endorphins, compounds that act like morphine to deaden the pain. The result is a type of euphoria.

"Mesmerize is the word that comes to mind," McKenna said. "When you combine this with the lyrics and the intensity, you have an hypnotic or mesmerizing state where people can be encouraged to act out certain behavior.

"A band member on stage might reach out with his hand in a motion that suggests he wants people to come toward the stage. That's all it takes. That's a signal to thousands of people to come forth.

"We have found in most cases that the behavior is acted out once the concert-goers are out of the building. That's because the security usually is tight and regulates them while in the building. The behavior generally is violent. We see a lot of vandalism and fights outside the building."

Dr. Lewis B. Hancock, a Salt Lake family therapist who has attended rock concerts as a member of the Salt Lake County Commission on Youth, said it's impossible to escape the music.

"There is no way to be in the Salt Palace without being totally enveloped by the music. You can't help but be absorbed by it even if you don't like the music," Hancock said. "There are huge walls of speakers that put out a sound that impacts your whole body. You could hear the base hit your chest. It took four days (after the concert) before a high-pitched ringing in my ears left."

Besides the three trampling deaths, other incidents occurred Friday at the concert. Police reports said 25-year-old Larry Mitchell fell 25-30 feet from a stairway to a fountain while trying to hurry from an upper to a lower level.

Another report described a fight in which the combatants knocked a nearby 20-year-old woman down some stairs, hitting her head against the cement.

The woman refused to be taken to a hospital and went back to the concert.