Aug. 5, 2008 -- Want to know why Tiger Woods is so good at golf? It may be because when his game is on, he sees the hole as bigger than it really is.
At least that's one implication in a study of how perception affects performance -- or possibly the other way around, how performance affects perception.
Jessica Witt, a research psychologist at Purdue University and a world-class athlete herself, is the lead author of a report on the research in the current issue of Psychonomic Bulletin and Review. Conventional wisdom holds that perception is based chiefly on visual cues that come into the eye, but Witt thinks that's only part of the story.
Her research, both on golfers and softball players, indicates that actual performance plays a key role in how athletes see their environment. Some of the cues are coming from their performance, not their eyes.
Witt and her fellow researchers, Sally A. Linkenauger, Jonathan Z. Bakdash and Dennis R. Proffitt of the University of Virginia, Charlottesville, conducted three experiments involving both experienced golfers and duffers, to see if playing well, or badly, affected their perception of the size of the hole.
The results showed that only the players who were playing well perceived the hole as being bigger than it really is.
"Only actual performance affected the recalled sizes of the golf cup," the study says. The players who thought they were playing well, but really were not, did not see the hole as bigger.
So, does that mean perception affects performance, or is it the other way around?
"At this point it's completely up in the air," said Witt, a member of the U.S. Frisbee team that won the 2005 gold medal at the World Games. "If I were to speculate, I would say it's probably both ways. If you see a bigger hole you are going to be more confident, and that may actually make you putt better." But she can't rule out the possibility that you see a bigger hole because you are putting better. Confusing, eh?
It may sound like much ado about nothing, but there's a serious side to the research, sponsored by the National Institutes of Health. If perception affects performance, it may be possible for people to improve their performance by mastering their perception. Witt said that's what she's working on now.
All this began when Witt noticed that a lot of media reports quoted athletes who saw the size of the golf cup, or the size of a soft ball, as different, based on their performance.
"Golfers have said that when they play well the hole looks as big as a bucket or basketball hoop, and when they do not play well they've been quoted as saying the hole looks like a dime, or the inside of a donut," she said. In previous studies she found that softball players who played exceptionally well saw the ball as bigger than players whose performance left much to be desired.
In the first of three experiments, 46 golfers were asked to estimate the size of the hole after playing a round of golf. The golfers selected from a poster with nine black holes that ranged from nine to 13 centimeters. Those who played better than their handicap judged the hole to be larger than its 10.8 centimeters. Those who played below their handicap judged the hole to be smaller.
Two subsequent studies found the same pattern when the hole was no longer in view, and when they could still see the hole, thus ruling out the role of memory. And again, the results were consistent, achievers saw it as bigger, losers saw it as smaller.
Witt thinks this optical illusion could play a role in streaks and slumps.
"Does the perception that the hole was bigger, or smaller, than it really is persist?" she asked. "Does it perpetuate itself? Then perhaps it's linked to streaks and slumps."
Even the best golfers experience periods when they are hot, or cold. Could it be because the hole appears larger over an extended period of time, or smaller?
Of course, the golf cup is only one of many obstacles on the course, but Witt think the perception of size extends to other parts of the game.
"Putting is where you score, so I think the hole is a big factor," she said. "But I think you would find similar effects on other parts of the course. The green probably looks a lot farther away if you are having trouble getting it there, and the fairway probably looks so much more narrow if you are slicing the ball, and the sand trap probably looks a lot bigger."
"So I think this effect is probably prevalent throughout the whole round."
And it probably has an impact in all sports, she added, although in some cases it's harder to measure.
Wind can be a demon in her favorite sport of Frisbee, she said, "so if somebody is upwind they probably look farther away compared to someone who is downwind." Now she would like to figure out how to use that information to her advantage.
"It's possible that by using this information we can develop various ways to improve performance, based on what we know about perception," she said. "We're actually working on some things right now to make that happen. If it works, we'll let you know."
Lee Dye is a former science writer for the Los Angeles Times. He now lives in Juneau, Alaska.