Summary: Neurocomputing 32}33 (2000) 643}650
The ecology of gaze shifts
Dirk Brockmann*, Theo Geisel
Max-Planck-Institut fu( r Stro( mungsforschung, Department of Nonlinear Dynamics, Postfach 2853,
Bunsenstr. 10, D-37073 Go( ttingen, Germany
Accepted 13 January 2000
We present a phenomenological model for the generation of human visual scanpaths.
Successions of saccadic eye movements are treated as realizations of a stochastic jump process
in a random quenched salience "eld. E$ciency of the process is de"ned in terms of convergence
properties of the time-dependent probability of "xating a region in the visual environment.
Based on the assumption that the visual system minimizes the typical time needed to process
a visual scene, our theory predicts that scanpaths are geometrically similar to a prominent class
of random walks known as LeH vy #ights. The theory is well con"rmed by psychophysical
experiments. 2000 Elsevier Science B.V. All rights reserved.
Keywords: Vision; Gaze shift; Saccade; LeH vy #ight; Visual salience
The visual system of primates achieves highest resolution in the fovea. In the
periphery, visual resolution rapidly decreases. The loss of visual acuity is compensated
by a succession of rapid eye movements known as saccades. Saccades actively