The Frontal Cortex

Little kids love McDonald's:

Hamburgers, french fries, chicken nuggets, and even milk and carrots all taste better to children if they think they came from McDonald's, a small study suggests.

In taste tests with 63 children ages 3 to 5, there was only a slight preference for the McDonald's-branded hamburger over one wrapped in plain paper, not enough to be statistically significant. But for all the other foods, the McDonald's brand made all the difference.

Almost 77 percent, for example, thought that McDonald's french fries served in a McDonald's bag tasted better, compared with 13 percent who liked the fries in a plain white bag. Apparently carrots, too, taste better if they are served on paper with the McDonald's name on it. More than 54 percent preferred them, compared with 23 percent each for those who liked the unbranded carrots and those who thought they tasted the same.

When I first read about this study, I was a bit surprised by the magnitude of the preference shift. After all, most three year olds have trouble deciphering the meaning of advertisements, especially when they aren't targeted at kids. But then I remembered the mere exposure effect, which was first discovered by Robert Zajonc, a psychologist at Stanford. In a seminal 1980 paper, "Feeling and Thinking: Preferences Need No Inferences," Zajonc used a series of clever experiments to demonstrate that our brain always prefers the familiar. For example, if people are repeatedly exposed to a random Chinese ideogram, they begin to prefer that ideogram to other Chinese characters, even though they can't explain why. This irrational preference persists even if people are shown the Chinese ideogram subliminally, so that they have no conscious awareness of seeing it. A split second of perception is enough to generate a persuasive emotional reaction, as the preferences of the unconscious can be shaped by the merest of exposures. (Familiarity makes favorites.) Saturating our sensations is a sure way to increase sales.

I think the mere exposure effect also explains the preference shift towards McDonald's in little kids. The scientists found that the more television the children watched, the more they preferred food with a fast food label. So even if the little kids didn't understand the advertisements for the new southwestern chicken salad at McDonald's, or comprehend those billboards for McDonald's ice coffee (which is pretty good, by the way), they were exposed repeatedly to the golden arches, and that exposure made them like the brand.

This unconscious response is a leftover idiosyncrasy from our distant past. Back in the Pleistocene era, when humans were vulnerable hunter-gatherers, it made sense to instinctively prefer the familiar. The strange was dangerous: new foods might be toxic and adventurous eaters got poisoned. Of course, these evolved feelings aren't particularly helpful in the modern marketplace. Instead of keeping us safe, they keep us tethered to brands with big advertising budgets, like McDonald's.

What else can the mere exposure effect explain? For example, I've always wondered if the mere exposure effect can help explain why so many dictators insist on plastering their image all over the place.