Three-quarters of U.S. TV viewers read the newspaper while they watch TV, and two-thirds are online while they watch TV, according to a study released by The Media Center at the American Press Institute.

Because 70 percent of media users attempt to use two or more forms of media at once, the study questions deeper implications for marketers, advertisers and content providers on who is paying attention to what, and when.

The study found that 74.2 percent regularly watch and read the newspaper simultaneously, 66.2 percent regularly or occasionally watch TV while going online. While waiting for Internet downloads, 52.1 percent listen to the radio, 61.8 percent watch TV and 20.2 percent read the newspaper.