23(4) 397 –399
© The Author(s) 2012
Reprints and permission:
One of the reasons we (the authors) enjoy going to live col-
lege basketball games is to watch the antics of the student
section. We love watching the students’ creativity in trying to
pump up the home team and distract the visiting team, espe-
cially during free throws. Such escapades made us question
whether manipulating what athletes see can influence their
Perception is clearly important for performance. For
instance, when athletes look directly at a target without mov-
ing their eyes around—a pattern known as the quiet eye—they
are more successful in making free throws, putting, and per-
forming a variety of other tasks (e.g., Vickers, 1996, 2007).
The quiet eye might lead to more successful performance by
focusing attention on targets, and helping athletes to ignore
distractors. Additionally, the quiet eye might change the way
targets look. Targets presented in the fovea look bigger than
those in the periphery (Newsome, 1972), so the quiet eye
might lead athletes to perceive targets as bigger.
Misperceiving a target as bigger could influence perfor-
mance in one of three ways. It could disrupt performance
because the observer might aim for a location that does not
correspond with the target. In this case, the misperception
would result in worse performance. However, actions and
explicit perceptions may not be influenced by illusions to the
same degree (Goodale & Milner, 1992). That is, there may be
dissociations between perceptions and visually guided actions
such that illusions, which fool conscious perception, do not
influence subsequent actions (e.g., Ganel, Tanzer, & Goodale,
2008). In this case, misperceiving a target as bigger would not
affect performance. A final alternative is that misperceiving a
target as bigger could enhance performance. Bigger targets
feel as if they should be easier to hit, so people may feel more
confident when aiming for a bigger target. Given that increased
confidence improves performance (e.g., Woodman & Hardy,
2003), a perceptually bigger target may also lead to enhanced
performance. Here, we report an experiment in which we
tested these possibilities.
Thirty-six participants (19 females, 17 males) putted to two
different-sized holes (5.08 cm and 10.16 cm in diameter; both
10 cm in depth). A downward-facing projector displayed a
ring of 11 small (3.8 cm in diameter) or 5 large (28 cm) circles
around each hole to create an Ebbinghaus illusion. For each
hole and illusion combination, participants stood at a com-
puter approximately 1.7 m from the hole and used MS Paint to
draw a circle that matched the hole’s size. Then, they attempted
10 putts from a distance of 3.5 m, and we recorded how many
balls dropped into the hole. Presentation order was counterbal-
anced across participants. Data from 4 participants were
removed because these participants were outliers, as deter-
mined by box-plot graphs.
The illusion influenced perceived size of the 5-cm hole, t(31) =
2.87, p < .01, d = 0.51, and subsequent putting performance,
t(31) = −2.66, p < .05, d = 0.54 (see Fig. 1). Participants made
more successful putts when the 5-cm hole was perceptually
larger. The surrounding circles did not influence perceived
size of the 10-cm hole, t(31) = 0.77, p > .44, d = 0.14 (small
surround: M = 10.50 cm, SD = 1.74; big surround: M = 10.38 cm,
SD = 1.89). We are unclear why the surrounding circles did not
induce an illusion for the 10-cm hole, though the surrounding
circles were smaller relative to the 10-cm hole than to the 5-cm
hole, and smaller surrounding circles have less of an effect on
perceived size in the Ebbinghaus illusion (Roberts, Harris, &
Yates, 2005). Given the lack of an effect of the surround on the
perceived size of the 10-cm hole, this served as a control con-
dition that allowed us to examine whether putting performance
was influenced by apparent size or by other factors related to
the surrounding circles. For the 10-cm hole, we found that per-
formance was not affected by the surrounding circles, t(31) =
0.37, p > .71, d = 0.07 (small surround: M = 3.69 successful
putts, SD = 1.67; big surround: M = 3.83 successful putts, SD =
1.88). This suggests that the significant effect of the surround
Jessica K. Witt, Department of Psychological Sciences, Purdue University,
703 Third St., West Lafayette, IN 47907
Get Me Out of This Slump! Visual Illusions
Improve Sports Performance
Jessica K. Witt1, Sally A. Linkenauger2, and Dennis R. Proffitt3
1Department of Psychological Sciences, Purdue University; 2Max Planck Institute, Tübingen, Germany;
and 3Department of Psychology, University of Virginia
Received 3/24/11; Revision accepted 10/13/11
Witt et al.
on putting to the 5-cm hole was due to the hole’s perceived size,
rather than other factors related to the surrounding circles.
Participants putted more successfully to the perceptually bigger
hole. As outlined in the introduction, this result suggests a link
between perceived size and performance. A likely explanation
for this effect is that an increase in the apparent size of the target
increased participants’ confidence in their abilities, which in
turn improved performance (Woodman & Hardy, 2003).
The results do not support the prediction of a dissociation
between perception and action, as might be expected by the
two-visual-streams hypothesis (Goodale & Milner, 1992).
However, putting is different from the kinds of actions typi-
cally studied with respect to this hypothesis. Once the ball is
struck, try as one might, one cannot change its path. Ballistic
actions such as putting might not benefit from additional on-
line visual processing in the same way as visually guided
actions such as grasping can (Glover & Dixon, 2001). Thus,
our demonstration of a link between perception and perfor-
mance does not challenge the idea of a separate visual process-
ing stream for visually guided actions.
This study extends the action-specific account of percep-
tion, according to which people perceive the environment in
terms of their ability to act in it (Proffitt & Linkenauger, in
press; Witt, 2011). For example, in one study, softball players
who were hitting better than others judged the ball as bigger
(Witt & Proffitt, 2005). Similar patterns of results have also
been demonstrated for throwing darts (Wesp, Cichello, Gracia,
& Davis, 2004), kicking field goals (Witt & Dorsch, 2009),
returning tennis balls (Witt & Sugovic, 2010), and golfing
(Witt, Linkenauger, Bakdash, & Proffitt, 2008), as well as for
children throwing balls to a target (Cañal-Bruland & van der
Kamp, 2009). The action-specific account suggests that suc-
cessful performance causes the action’s target to be perceived
as bigger than it is perceived in the case of unsuccessful per-
formance. Here, we demonstrated the reciprocal relationship:
Seeing the target as bigger leads to a subsequent improvement
Could this reciprocal relationship between perception and
performance be one of the mechanisms underlying streaks and
slumps? To answer this question, one would first have to test
if these effects are cyclical, with perception and performance
continually influencing each other. Regardless, our results
suggest that our visual-illusion paradigm could be used to
induce the perception that a target looks bigger, which would
then lead to improved performance and might help an athlete
get out of a slump.
Declaration of Conflicting Interests
The authors declared that they had no conflicts of interest with
respect to their authorship or the publication of this article.
This research was supported by a grant from the National Science
Foundation (BCS-0957051) to J. K. W. and a grant from the National
Institutes of Health (RO1MH075781) to D. R. P.
Perceived Size (cm)
(No. of Successful Putts)
Fig. 1. Perceived size of the 5-cm hole (left panel) and participants’ performance putting to that hole (right panel) as a function of the
size of the surrounding circles. Error bars represent 1 SEM.
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