July 9, 2012 at 4:19 PM ET
Whenever I’ve watched video of myself on TV, I think I look shifty-eyed. I’m asked a question and my eyes dart away from the camera into which I’ve been told to look. At the time, I don’t know I’m doing it, but I am.
Psychology professor Howard Ehrlichman of Queens College, City University of New York, has been studying eye movement since the 1970s. In a recent article in Current Directions in Psychological Science, he reviewed some of his work, including recent findings, and argued there’s robust evidence that I’m not being shifty-eyed at all. I’m just thinking. More specifically, I'm accessing long-term memory.
“There’s no way to prove this is universal,” Ehrlichman says. “But I can say that you can see it just by looking at people on TV, and in interviews. I am convinced it is universal.”
Ehrlichman is referring to saccades, rapid eye movements that disengage the focus of one’s vision, often moving down and away from, say, the eyes of a person to whom you are talking. Or a TV camera.
Over the years, there have been a number of seemingly logical explanations for the darting eye phenomenon. Humans place great importance on the eyes of others -- it’s part of how we determine friend from foe or intuit what others are thinking. Because this requires brain power and focus, many believe we have to disengage in order to direct our thoughts elsewhere. Another theory suggests that the direction of eye movement is related to the hemisphere of the brain we're accessing. That idea even showed up as a plot point in an episode of “The Mentalist.”
Sadly, Ehrlichman, says, “people in law enforcement do believe that,” and think they can tell if somebody is telling the truth or not. But during his work for his Ph.D. dissertation he found little evidence to support the idea.
In fact, Ehrlichman’s research shows that these eye movements have nothing at all to do with vision or hemispheres. He speculates the intermittent eye movements are an evolutionary holdover.
Most animals are what Ehrlichman calls “sensory/motor machines.” They are constantly scanning and reacting to the environment, looking for food, say, or trying to avoid danger. When they find what they are looking for, they fixate on it.
Our brain’s long-term memory is like an internalized landscape. We don’t need our eyes to scan it, but “our eyes go along for the ride,” Ehrlichman says, even if we’re not looking for anything visual.
Ehrlichman and his colleagues proved the saccades are unrelated to actual vision by putting people in dark rooms, alone. “We see this effect even if they have closed eyes and they have nothing to disengage from,” he says. “The pattern is the same as when people are sitting with their eyes open.”
In one experiment, subjects were asked to name things according to visual properties, like “green” or “triangular” versus naming words meaning the same as “pleasant.” The visually-related items like “green” evoked no eye movement. But when subjects searched their brain data banks for words matching pleasant, the saccades were obvious.
Similarly, when subjects were asked to visualize their living room and describe it, which you’d think would lead to lots of eye movement as they mentally scanned the room, there was virtually no saccade activity.
“We think once they retrieve the image, they can move through it without searching long-term memory,” Ehrlichman explains.
On the other hand, when an answer to a question is right in front of us, say if we’ve just rehearsed a Q and A, we don’t need to scan our internal memory landscape. We can pop out an answer to a question and maintain our focus.
So rather then being shifty, eye movements could actually mean somebody -- including yours truly -- is simply being thoughtful.
Brian Alexander (www.BrianRAlexander.com) is co-author, with Larry Young PhD., of "The Chemistry Between Us: Love, Sex and the Science of Attraction," (www.TheChemistryBetweenUs.com) to be published Sept. 13.