The Advertising Research Foundation (ARF) has a simple message for brand marketers wondering about the return on investment of their advertising dollars: the more platforms the better. And it has more than a decade of research to prove it.

Among the ARF’s How Advertising Works initiatives is what it calls its Ground Truth experiments, one of which studied 12 years of data, 5,000 campaigns and $375 billion in advertising expenditures, according to Gayle Fuguitt, the organization’s CEO and President.

“We looked at the effectiveness of different platforms in building ROI and we discovered that more platforms are better,” Fuguitt says during a break at Simulmedia’s annual PeopleFront event. “The strongest interaction between two platforms is television plus digital. That yields a dollar and sixty cents of ROI, 60 percent greater ROI than just television alone.”

As marketers shift dollars to digital instead of adding dollars, “our advice is add back television if you’re shifting to over to digital,” Fuguitt adds. “Make sure you have that combination. Because there’s really strong interaction. They happen across other platforms too, but that’s the most powerful.”

She cites other research, by Facebook at Neuro-Science, showing the “Priming effects” of advertising messages shown on mobile devices and during TV programming. The use of neuroscience helps to show that ads can unlock consumers’ emotional connections via their heart, pulse and brain, not just their binary behavior to understand how advertising interactions can help build brand loyalty.

“If you see an advertisement on a mobile phone and then on television you will have even more effectiveness,” says Fuguitt. “It resonates better. We know that brands are built in the brain.”

Noting that 30% of marketers are only advertising on one platform, Fuguitt describes TV as undergoing redefinition but still relevant and important, “even with Millennials.”

We interviewed her in New York at the Simulmedia PeopleFront conference where she was a speaker. Please find more video interviews from the PeopleFront event right here.