We measured anticipatory smooth eye movements and smooth pursuit initi
ation with predictable and unpredictable step-ramp stimuli in normal s
ubjects. Subjects generated anticipatory eye motion before targets mov
ed and during intervals when targets suddenly disappeared. Expectation
s of target trajectory modified pursuit acceleration and latency, demo
nstrating that pursuit initiation is not governed by visual inputs alo
ne. Anticipatory smooth eye movements and predictive contributions to
smooth pursuit had similar accelerations and velocities. Anticipation
and pursuit initiation varied in parallel between subjects; anticipati
on was stronger in subjects who generated faster smooth pursuit. These
findings imply that anticipatory and smooth pursuit eye movements are
governed by a common mechanism.