by ROBERT MARTONE
Research documents a strange illusion
Have you ever sensed that someone might be watching you? You get a prickly feeling at the back of your neck and turn to see a stranger staring at you across the room. It sometimes seems that we can feel a person’s gaze as a physical sensation. And, from a single glance, we can tell a lot about a person, such as their moods, intentions and focus. Is their gaze dangerous, interesting or attractive? Do they stare directly or glance to the side? If “eyes are the window into the soul,” then a glance reveals far more than we know.
Recent studies demonstrate that humans attribute gaze with physical properties. We create tacit mental schemes in which the visual attention of others is computed as a forceful beam emitted from the viewer’s eye and directed at the object of interest. These mental schemes allow us to take cognitive shortcuts to process peoples’ visual attention quickly and efficiently.
Gaze is an elemental form of communication that can coordinate activities and convey social dynamics without a gesture or spoken word. It requires a rapid interpretation of the meaning behind another’s gaze, but the trade-off for the speed of that interpretation is the mistaken understanding of gaze as something that can move things in our environment. These studies show that this interpretation is subconscious and automatic, and that it occurs even in those who would consciously deny that vision exerts any force.
You might expect that such an erroneous interpretation would be detrimental. In fact, while there seem to be few if any adverse consequences these findings may underlie rich and diverse cultural references to the outward force and power of the gaze. The results of the experiment demonstrate an ancient human idea linking gaze with physical properties. This notion, as old as the Greeks, is known as the “extramission” theory of vision. Extramission literally means “sending out,” and the extramission theory is the belief that vision is a force emitted from the eye. It is an intuitive understanding of vision common among children that persists among many adults. In contrast, the modern visual theory is called “intromission,” and is based on the notion that vision results from light entering the eyes.
Using a series of ingeniously simple experiments in one study, researchers found that subjects associate gaze with a physical force. Subjects viewed a computer display that had an image of a tube, roughly the size of the end of the paper towel roll, standing vertically on a table. At one end of the table was an image of a face gazing at the tube (researchers dubbed the face avatar Kevin). Subjects were instructed to tilt the tube towards Kevin’s image using specific keys on a keyboard until they felt the tube had reached the critical angle at which it would tip over. The critical angle reported by subjects depended upon whether Kevin was blindfolded. If Kevin was perceived as gazing at the tube, the critical angle was greater than when Kevin was blindfolded, suggesting that his gaze was impressing some force upon the tube that needed to be overcome for the tube to fall.
Scientific American for more