For some, the quick prick of a needle at the doctor’s office is no big deal. For others it can be a nightmare. New research suggests that the difference could lie in what you’re looking at.

Researchers simulated needle pricks by giving participants a little shock to their hand. As they did that, subjects had to watch three different videos. One was of a needle pricking a hand, another was of a Q-tip touching a hand, and the third was just a hand all by its lonesome self.

Subjects who watched the hand being pricked while they were shocked found the pain far more intense than those who watched a Q-tip or nothing at all.

The researchers also tried telling patients which one—the needle or the Q-tip—would be more painful. If the patients expected the Q-tip to be worse, they felt worse when watching the Q-tip, and vice versa. The work was published in the journal aptly named Pain. [Marion Höfle et al., "Viewing a needle pricking a hand that you perceive as yours enhances unpleasantness of pain"]

So the next time you’re at the doctor’s office getting ready for a shot, take the advice often offered by mountain climbers: don’t look down.

—Rose Eveleth

[The above text is a transcript of this podcast.]