The Neuroskeptic points out a recent study seeming to indicate that if someone replaced your normally caffeinated coffee with decaf this morning, you may not notice the difference, but your performance would decline.

The researchers set out to determine if coffee’s impact on performance was more placebo effect than fact, and chose an interesting design to do it. To make sure they were separating fact from fiction (or caffeine-generated effect from placebo), they added an additional twist: in some cases subjects were told the caffeine in the coffee would enhance their performance, and in others they were told performance would be impaired. Now I’m not saying coffee drives over-achieving, but the caffeine drinkers who were told their performance would be impaired actually did even better. (Actually, given the study design, one couldn’t make this conclusion, but as a coffee drinker, I could barely resist the conclusion once I saw the picture of the results.)

If you like coffee or are considering taking up the caffeinated habit, you can check out the official study publication, or the Neuroskeptic’s English translation, which may also bring back fond memories of Seinfeld and Jerry’s Morning Thunder. “He loves it. He walks around going, ‘God, I feel great!’”