Not to mention, the surge of glucose from eating the sugar cubes could've very well affected sentiment and responses. Daniel Kahneman talks about this in his book, specifically how groups given a chocolate bar in between tasks performed better than control groups, presumably due to the brain's dependence on glucose, and its fatigue in the lack thereof.

Recent evidence suggests that glucose depletion doesn't seem to affect the brain. For example, [1]. Moreover, the calorie consumption of the brain is basically constant regardless of what it is doing. I would hazard an untrained guess based off of these that the difference is in changes due to the body knowing of consumption of glucose versus any direct effect of the glucose itself. See also the study that athletes performed better after swishing a sweet drink in their mouth and spitting it out just as they did when actually drinking it.

[1] http://www.epjournal.net/wp-ontent/uploads/ep08244259.pdf

The link is broken, could you please post the title and author? Thanks!

Looks like it's missing a "c":

http://www.epjournal.net/wp-content/uploads/ep08244259.pdf

Yes, thanks for the correction! And for the sake of posterity, it's "Does the Brain Consume Additional Glucose During Self-Control Tasks?" by Robert Kurzban

might have been this?

http://www.runnersworld.com/drinks-hydration/when-and-why-to...

Really interesting. Thanks for the link!

Your alternative explanation is awfully close to "chewing". Chewing is a mild distraction.

My (main) point is that with so many uncontrolled variables, there are many alternative explanations that might have equal justification.

Of less importance (to me) is that my alternative explanation relies not on some physical act (chewing) somehow blocking brand awareness, but rather on the experience-seeking brain being idle or already-engaged when shown ads.

Again, with at least 6 uncontrolled variables, we could come up with dozens of things, from blood sugar trajectories to brain activity to chewing to smelling etc., all of which could be the actual trigger blocking brand awareness. I'm not partial to any one explanation given the paucity of data.

Not close enough for them to make the argument that the result is because "chewing disrupts the subconscious mouth movement that cements the brand name in your mind".

I'd add that playing with pop corn in the hand, feeling its texture, the smell and the small noise tend to steal the brain's focus from the ads. Indeed once the sugar is melted there is less to experience with the body.

Simpler.

The taste of sugar is perceived as positive. This puts you in a better mood. This makes you likelier to associate the ads with positive feelings. This in turn makes it likelier for you to react to ads because you associate those products with positive emotion.

Brains are really good at association. Really bad at cause and effect.

If you want to prove this to yourself, take a date out on a roller coaster or bungee jumping. When your hearts are racing and you feel alive, look at each other. The association you form pretty much guarantees a positive date, even though the person you were with had nothing to do with the adrenaline rush.

Perhaps they could have given some people liquid smoothies and others more solid smoothies with chunks of fruit.

Its easy to poke holes in any applied methodology. I could suggest the time of day wasn't consistent across groups, the seating position might introduce bias etc. But you have to start an investigation somewhere, and I think their methodology was a reasonable balance of practicality.

The work is tantalising evidence for something else going on. Which certainly warrents follow up work. Even if it was just the people were bored and not paying attention to ads, it still has consequences for the cinema business model.