Our Brains Can't Chew Popcorn and Listen At The Same Time

One of the conclusions we reached in our brain synchrony work is that when different parts of the brain (sound, text, patterns, colors, movement, for example) are stimulated at the same time from the same stimuli, that helps us retain messages. So when scientists found that chewing while listening disrupts comprehension, we were not surprised. 

According to Bloomberg Businessweek (10/28/13) and as reported by Cool News, researchers at the University of Cologne conducted a test where half the subjects were given a sugar cube during the pre-movie commercials, while the other half was given popcorn. A week later, all of the subjects were exposed to images of the advertised products and the "sugar-cube moviegoers had a clear preference" for them "while the popcorn eaters didn’t. In other words, the ads hadn’t stuck with them

The result had nothing to do with popcorn, per se. The reason is that when people read or hear something, "the brain simulates the corresponding muscle movement of the throat and mouth … Chewing, however, disrupts the process by monopolizing the speech muscles (unlike eating a sugar cube, which dissolves on its own), effectively drowning out any subvocalization and, with it, the process of familiarization." 

An earlier study produced a similar result when subjects were chewing gum (or not). The research undermines conventional wisdom that "mere exposure" to an image or message "predisposes people to liking it." It also "has ramifications" beyond advertising, as "there are plenty of settings in which people are trying to absorb new information while eating – the working breakfast, the client dinner, the lunch consumed resentfully at one’s desk while trying to catch up on e-mail. Those might all be occasions in which we’re not taking in information as easily as calories."