Figure 7.

Validation of calculation of the gaze/surface intersect location using a behavioral “food pellet” test. Black lines show sequential intersections of the gaze with the surface of the walkway along the X (A) and Y (B) axes when the cat walks on the flat surface where three food pellets were placed in different locations. Grey lines around the black one outline the area that projected to the area centralis of the retina. Positions of the food pellets are shown by dashed red, pink, and purple lines. An overlap of gaze and pellet lines along both axes indicates gaze fixation on the pellet, and vertical dashed arrows align beginnings of gaze fixations on each of the three pellets. The blue line shows the position of the cat’s eye. See also supplemental Video 1; it shows the movement of cat’s gaze along the surface and the movement of the head (the center of the left eye) in the corridor during a trial, in which a single food pellet was placed on the floor of the walkway.