Every generation is afraid of the next generation's music. But why? Is it the fact that people become less accepting as they grow older? Or has popular music become that much more risque?

In 1956, the King of Rock & Roll, Elvis Presley made an appearance on the Ed Sullivan Show, and when he swung his hips along with 'Hound Dog,' the audience had a unique reaction.

"Back in those days, that was just absolutely scandalous, completely and totally scandalous," says Ann Applegate, Associate Lecturer of Music at the University of Wisconsin-Marathon County. "We don't think twice about that now."

But Applegate says that was only one early moment in a history of shocking events in popular music.

And if crowds in the 50's thought Elvis was controversial, they were in for a surprise during the next decade.

Applegate adds, "Both Janis Joplin and Jimi Hendrix, who were incredibly flamboyant, incredibly outspoken with their music and with their performing styles, and because of that, I think were found by many to be very shocking."

Jeff Erickson, Director of Instrumental Music at UW-MC adds, "Sure, the lyrics too, you look at the Beatles and 'Lucy in the Sky with Diamonds', and the drug references that they refer to."

But as became a recurring scene from generation to generation, some people in the 60's found it more shocking than others.

Applegate adds, "That whole philosophy, that I think to many was shocking, but again it's a generational thing, the people the music was targeted for, they didn't find it so shocking. Their parents? Oh my goodness."

But just as rock music was becoming accepted by the masses, another genre came along to scare them all again.

Erickson says, "You know punk music, some of the artists, the Ramones and the Clash, people like that, their stated purpose was to shock people, because they felt that the music has gotten too tame... And I think it refers back to that social change aspect of music that rock & roll had in the beginning, and I think they sort of wanted to refer back to the roots of that."

And as the anger, piercings, and mohawks of punk scared crowds in the 70's and 80's, other performers found different ways to shock.

Erickson says, "You get into Madonna in the 1980's, there's a very overt sexuality in that."

Applegate adds, "When she first started coming out with her wardrobe, or what her concept of wardrobe was, so many people went, 'Oh my goodness'... Once we get over that shock, the shock factor wears off, and then, 'Okay, are you going to shock me with something else, or are we going to become acquainted with everything?'"

But Applegate says even people like herself who have witnessed a lot of controversial acts still find themselves shocked at where popular music ends up, and for her, it's rap music.

"So much within the lyrics of that, I find not only shocking, but for me, again personalizing it, reprehensible, some of the things that they say... I do find it shocking that so many people listen to it, that so many people enjoy it, that so many people buy it."

But as generation after generation have shown, music always seems to be on the cutting edge of change, and that may be more than coincidence.

Erickson says, "Artists often times are the first people to see change coming, and often times that's reflected in the music... People want change, they don't want to listen to the same sorts of things, so in a way, artists are always trying to find something that's going to be the next popular thing as well."

And no matter what younger generations think, eventually they too will be shocked at what popular music has become.

Applegate says, "There's going to come a time, especially when people of your generation become parents, that you're going to be listening to the music that your children listen to, especially as they become adolescents, and you're going to go, 'Oh my goodness.'"

Erickson adds, "I don't know what the next shocking thing will be, but I'm sure there's something just around the corner."

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