Can listening to sexually aggressive lyrics prompt teenagers to have sex at an earlier age?
That's the issue raised by a new study, and it could unleash a fierce debate over whether a teen's music player is potentially risky and, if so, what should or can be done about it.
In an unusual piece of research, investigators at the University of Pittsburgh graded the sexual aggressiveness of lyrics, using songs by popular artists on the US Billboard chart.
The lyrics were graded from the least to the most sexually degrading.
They then asked 711 students aged 15 to 16 at three local high schools about their music preferences and their sexual behaviour.
Overall, 31 per cent of the teens had intercourse.
But the rate was only 20.6 per cent among those who had been least exposed to sexually degrading lyrics but 44.6 per cent among those highly exposed to the most degrading lyrics.
The study's lead author, Brian Primack, said music by itself was not the direct spark for sex but helped mould perception and was thus "likely to be a factor" in sexual development.
"These lyrics frequently portray aggressive males subduing submissive females, which may lead adolescents to incorporate this 'script' for sexual experience into their world view," he told AFP.
The study took social factors, educational attainment and ethnicity into account.
"Non-degrading" lyrics described sex in a non-specific way and as a mutually consensual act, while "degrading" lyrics described sexual acts as a purely physical, graphic and dominant act.
The study did not give the names of songs or artists, but gave an example of degrading lyrics as "Wait till you see my dick / I'm gonna beat that pussy up".
-- It's a perennial debate that crops up --
"Lyrics describing degrading sex tend to portray sex as expected, direct and uncomplicated," said the paper, which appeared last week in the American Journal of Preventive Medicine.
"Such descriptions may offer scripts that adolescents feel compelled to play out, whether they are cast in the role of either the female or the male partner."
Steven Martino, author of a study published in 2000 that also made the same association between music and sexual behaviour, said the findings were a wake-up call.
"The need [is] for parents to be aware so that they can place limits and criticise and understand what their children are listening to," said Martino, a behavioural scientist in Pittsburgh with the Rand Corporation.
More than 750,000 American teenagers become pregnant each year, giving the United States one of the highest rates of teenage pregnancies in the rich world, according to figures quoted in the study.
Nearly a quarter of all female teenagers in the United States have a sexually-transmitted disease.
Nearly a quarter of a century ago, lyrics by Prince on his album "Purple Rain" prompted wives of senior politicians in Washington, led by Tipper Gore, to set up the Parents Music Resource Centre.
They pushed for the music industry to develop guidelines and a rating system for lyrics, similar to ratings for movies. The system was criticised by many as unworkable and counter-productive, making it more daring for teens to buy songs they deemed taboo.
"Government needs to help parents to regulate the industry," said Helen Ward, president of the Kids First Parents Association of Canada.
Today's technology means it is "physically impossible" for parents to monitor what their children listened to or watched on their MP3, she said.
But Raymond MacDonald, a specialist in music psychology at Glasgow Caledonian University, described it as "a perennial debate that cropped up with artists like Frankie Goes to Hollywood, the Sex Pistols and Elvis Presley before that".
"Do we really need a solution to the problem?", he asked.
MacDonald said that even if every generation rehashes the discussion differently, there's an important difference today: age lines have blurred and now everyone is listening to everything.
"Maybe we should do a study to see if the music has as a bad an influence on grandparents," he said wryly.