Limited-lifetime Gabor stimuli were used to assess both first- and second-o
rder motion in peripheral vision. Both first- and second-order motion mecha
nisms were present at a 20-deg eccentricity Second-order motion, unlike fir
st-order, exhibits a bias for centrifugal motion, suggesting a role for the
second-order mechanism in optic flow processing. (C) 2001 Optical Society
of America.