Overt Attention: Attending by Moving Our Eyes • 101● FIGURE 4.27 Sequence of fi xations of a person making
a peanut butter sandwich. The fi rst fi xation is on the loaf of
bread. (Source: M. F. Land, N. Mennie, & J. Rusted, “The Roles of Vision and Eye
Movements in the Control of Activities of Daily Living,” Perception, 28, 11, Figure 2
and Figure 8, 1311–1328, 1999. Copyright © 1999 by Pion Limited, London. All
rights reserved. Reproduced by permission.)
movement from the bread to the plate. The peanut butter
jar is then fi xated on, lifted, and moved to the front as its
lid is removed. The knife is then fi xated on, picked up, and
used to scoop the peanut butter, which is then spread on the
bread (Land & Hayhoe, 2001).
The key fi nding of these measurements, and also of
another experiment in which eye movements were mea-
sured as a person prepared tea (Land et al., 1999), is that
the person’s eye movements were determined primarily by
the task. Participants did not look at objects or areas that
were irrelevant to the task. Furthermore, the eye movement
usually preceded a motor action by a fraction of a second,
as when the person fi rst fi xated the peanut butter jar and
then reached over to pick it up. This is an example of the
“just in time” strategy—eye movements occur just before
we need the information they will provide.
Although eye movements often indicate where a person
is directing attention, it is possible to be looking directly at
something without paying attention to it. You may have● FIGURE 4.25 Pattern of eye movements to this picture of a
baseball game in PNC Park in Pittsburgh. The person looks at the
yellow stripe fi rst.
Bruce Goldstein● FIGURE 4.26 A wearable eye tracker. (a) The scene
camera and eye camera are mounted on a lightweight
glasses frame. The backpack carries a battery and a
video camera, which tracks eye position relative to the
scene the person is observing. (b) Image of a scene from
the head-mounted video camera while the participant
makes a peanut butter and jelly sandwich. Fixations are
indicated by the yellow circles. Circle diameters refl ect
the duration of the fi xation. (Source: M. F. Land & M. Hayhoe, (Source: M. F. Land & M. Hayhoe,
“In What Ways Do Eye Movements Contribute to Everyday Activities?” “In What Ways Do Eye Movements Contribute to Everyday Activities?”
Vision Research, 41,Vision Research, 41, 3559–3565, 2001. Figure b courtesy C. A. Rothkopf 3559–3565, 2001. Figure b courtesy C. A. Rothkopf
& J. B. Pelz, “Head Movement Estimation for Wearable Eye Tracker,” & J. B. Pelz, “Head Movement Estimation for Wearable Eye Tracker,”
Proceedings ACM SIGCHI Eye Tracking Research & Applications Proceedings ACM SIGCHI Eye Tracking Research & Applications
Symposium,Symposium, San Antonio, Texas, 123–130, 2004.) San Antonio, Texas, 123–130, 2004.)(a)(b)Copyright 2011 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part.