BOB GARFIELD: As we've seen, harmful or healthy is a question not likely to yield unanimous answers, whether about DDT, literature or as it turns out, media. Scientists worldwide are hard at work determining the effects of mass media on the human subject. Many humans, unfortunately, are too busy being affected, either positively or negatively, to keep track of the science. So, in the interest of keeping listeners up to date with the latest research on the media, we bring you the highlights of a year's worth of media studies. [HIGHLIGHTS MUSIC UP AND UNDER] We start with a study released last summer by researchers at the University of Washington. They found that for every hour of TV added to the average TV diet of toddlers, the likelihood that they would suffer attention problems by age 7 went up 10 percent. Also last summer, researchers in New Zealand determined that watching more than two hours of TV a day as a child makes it more likely that you'll grow up to be a smoker, overweight, out of shape, and with high cholesterol. In September, the Rand Corporation announced that teenagers who watch programming with sexual content, which incidentally was determined to be most of it, were more likely to initiate sexual intercourse. Monkey see, monkey do seemed to be the conclusion in that study, at least where sex was concerned. But could the explanation lie elsewhere? Scientists at the University of Florence in Italy last year announced that watching television may actually hasten puberty. Kids who were exposed to more TV than they were accustomed to started producing less melatonin, a hormone whose levels drop at the onset of puberty. When they were deprived of TV, their melatonin levels spiked. But lest you think all the research is being conducted by out of touch academics, we direct you to another story from last fall, this one from Nick at Nite and TV Land. It found that families who dine together are more likely to describe themselves as very satisfied with the closeness of their families, and to make other types of family activity a priority. High on that list of activities? Watching TV together. Which can have its own benefits - especially if you happen to be a homophobic family. A study released in April from the University of Minnesota found that exposure to positive portrayals of gay characters on TV shows, like Six Feet Under and Queer Eye for the Straight Guy can reduce prejudice among viewers. [SONG PLAYS]

WOMAN: [SINGING] OH, THINGS JUST KEEP GETTING BETTER…

BOB GARFIELD: So, TV can make us more sensitive, except when it doesn't. Also in April, researchers at the University of Washington reported that the more television four year olds watch, the more likely they are to become bullies later on at school. [BRIEF MUSICAL REFLECTION OF DISAPPOINTMENT] To review, TV leads to bullying, obesity, puberty, attention problems and sexual promiscuity, unless viewed with the rest of the family, in which case you are guaranteed happiness. [CRESCENDO] Or not. [MUSIC]