Viewers of “American Idol” last night may have had to rub their eyes during certain moments in the program: Were those TV commercials running at the same time as segments from the program?

In an expansion of an experiment begun last season, the 21st Century Fox-owned broadcast outlet is running more advertising in “Idol” that appears even as action from the program continues on the screen. The technique, which Fox calls a “double box,” because  it shows ad and program on-screen simultaneously in two separate graphic “boxes,” borrows a page from sports broadcasts from Time Warner’s Turner, Walt Disney’s ESPN and Fox Sports in an effort to keep viewers from channel surfing or fast-forwarding past the ads with a DVR.

Last night, Fox ran two “box breaks” during “American Idol,” with 13 commercials from 11 advertisers (Coca-Cola and Procter & Gamble each ran two spots). Last season, when Fox tested the idea, it ran just one break with three advertisers on board, and only on one night of “Idol.” Fox said Tuesday it planned to run the boxes twice more on Wednesday’s show.

The ads appear in one part of the screen while another section shows a live camera feed from the “Idol” stage, judges’ table  and backstage area.

Fox’s ability to split its screen between the ads and the show they support comes as consumers have demonstrated an increased willingness to seeing multiple graphic elements on their TV screens, a proclivity that appeared to have waxed along with added use of computer screens and tablets. TV networks themselves have accelerated the attitude by running pop-up promotions at the bottom of their screens during programming.

Fox is armed with findings from Innerscope Research, a Boston company that attempts to measure human biological response to commercials and TV programs. Innerscope found 2013’s “double box” ads during “Idol” spurred more emotional engagement and were remembered better than traditional commercials.

Products advertised last night alongside during Tuesday’s “Idol” split screen included Pantene, Diet Coke, Nasacort nasal spray, AT&T, Wendy’s, and Maybelline Color Sensational Buffs, all featured in what would otherwise have been the show’s third ad break. Meantime, ads for Diet Coke, Chili’s, Robitussin, Swiffer, T-Mobile, Walmart and Subway appeared in what would have been “Idol’s” seventh ad break of the night.