By Jill Hamburg Coplan

Hazardous to Your Message

Like other ads, public service announcements frequently rely on emotion-laden messages to involve viewers. But the tactic can backfire. Researchers at the University of Missouri measured viewers’ attention levels while they watched two dozen highly charged anti-tobacco ads. Some of the 30-second ads, created from 1998 to 2002, showed frightening images—an emphysema sufferer gasping for air, for instance. Others showed grisly scenes: an artery oozing during surgery or a diseased lung in a tray.

Both the scary ads and the blood-and-guts spots engaged the subjects (58 nonsmoking students) more effectively than anti-smoking ads that lacked emotional content. And they were easier for the subjects to recall accurately. But when a TV spot was both frightening and gory, the students’ attention wandered and their recall was poorer.

It’s possible people “just can’t process” all that emotion, says Glenn Leshner, a strategic-communications professor and the study’s lead author. He theorizes that viewers may tune out dire-and-disgusting ads because they sense danger and instinctively retreat. Heart rates were up among the students in his study who disengaged, he notes. “Maybe they were getting ready to flee.”