Our Mind-betraying Eyes

Thoughts are generally believed to be of the ether. Intangible, ephemeral, hidden from sight. But scientists are beginning to identify the many ways that cognitive abstractions are transferred to the physical world. Last week, researchers from Australia and Switzerland reported that they can essentially predict “what number you’re thinking of” with a look into your eyes. More accurately, they can predict the relative size of that number in a random series. The team had a group of participants call out 40 numbers (from 1 to 30) as randomly as possible. The researchers recorded the volunteers’ average horizontal and vertical eye position a split second before each number was called out, and were able to reliably forecast whether the next number would be higher or lower. When the subjects looked to the left and down, the number was smaller; when they looked up and to the right, it was larger. Not only did the direction of eye movement indicate the relative size of the next number, but surprisingly, the degree of movement predicted the magnitude of the numerical shift. This is great news if you’re a magician or a card shark. But beyond the purview of children’s birthday parties and card tables, the implications of the study are decidedly more profound. The results confirm earlier findings that we mentally reference an “imaginary number line” when thinking about numbers and make a solid case for how subtly these abstractions can direct body movements. They illuminate the remarkable connections between supposedly abstract thought processes, body mechanics, and the choices we make.—GB