Headed in the Right Direction: A Commentary on Yoshida and Smith

In 1984, I was jogging through the streets of Bloomington, Indiana, and came to an intersection just as a car approached on the cross street. The car slowed down for the stop sign, the driver looked in my direction, and I proceeded to jog in front of its path, confident that the driver was aware of my presence and would certainly not run the stop sign. I was wrong. After tumbling over the hood of the car, which hit me at perhaps 10 miles per hour, I ended up on the ground, with the panicked driver standing over me asking if I was okay (I was bruised but not broken). The point of this anecdote is that everyone takes for granted the inference that where someone looks, which is often based solely on head direction, is coincident with where that person is attending. The hard lesson I learned by that accident is that looking is not the same as seeing. Experimental psychologists have known for nearly a century that an excellent measure of visual attention is the direction of gaze (Buswell, 1922). Head direction provides a less accurate measure because the eyes can move within a 90° horizontal extent even when the head is stationary. A variety of methods were developed to measure gaze direction with exquisite detail, and some of these methods eventually migrated to the study of infants (see Aslin & McMurray, 2004). Unfortunately, the most precise methods were impractical, requiring fairly rigid head stabilization (Haith, 1969). When more flexible methods became available, most notably head-mounted eye trackers, they opened up a new perspective on how adults view their visual world under less restrained conditions. The head was now free to move, and in some cases the entire apparatus could be mounted on the person as he