Adaptation of the amplitude of saccadic eye movements is necessary so that saccadic accuracy can be maintained throughout life despite the changes caused by development, injury and aging. The long-term objective of this grant is to study the mechanism and site(s) of saccadic amplitude adaptation in non-human primates. We will address this issue in several ways. First, we will estimate the level of the saccadic system at which adaptation takes place by determining whether behavioral adaptation of reactive (more simple) saccades transfers to higher-order (more """"""""cognitive"""""""") saccades. Amplitude adaptation will be produced by requiring monkeys to track a stepping target that is jumped forward or backward during a targeting saccade, so that the adaptation mechanism is deceived into thinking that the saccade is in error. Over approximately 1000 such deceptions, monkeys gradually reduce this error by adjusting saccade amplitude. If adaptation of a reactive saccade does not transfer to a higher-order saccade, they must have different sites for saccadic plasticity. Second, we will record from the oculomotor cerebellar vermis during behavioral adaptation and assess the associated changes in simple spike and climbing fiber activity in Purkinje cells. We expect changes in neuronal firing that will indicate how the saccadic error delivered by the climbing fibers shapes the simple spike firing of Purkinje cells. Third, during behavioral adaptation we also will examine the change in activity of cells in the caudal fastigial nucleus (CFN), which receives direct inhibition from the vermal Purkinje cells and, in turn, projects directly to the premotor brain stem generator of saccadic eye movements. We expect that changes in firing of CFN cells will be appropriate to effect downstream structures to alter saccade amplitude. Because of the remarkable similarities of simian and human saccadic behavior, the results of these experiments should have considerable relevance in the diagnosis, treatment and rehabilitation of human patients with chronic saccadic disorders.

National Institute of Health (NIH)
National Eye Institute (NEI)
Research Project (R01)
Project #
Application #
Study Section
Central Visual Processing Study Section (CVP)
Program Officer
Araj, Houmam H
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of Washington
Schools of Medicine
United States
Zip Code
Kojima, Yoshiko; Fuchs, Albert F; Soetedjo, Robijanto (2015) Adaptation and adaptation transfer characteristics of five different saccade types in the monkey. J Neurophysiol 114:125-37
Knight, T A (2012) Contribution of the frontal eye field to gaze shifts in the head-unrestrained rhesus monkey: neuronal activity. Neuroscience 225:213-36
Kojima, Yoshiko; Soetedjo, Robijanto; Fuchs, Albert F (2011) Effect of inactivation and disinhibition of the oculomotor vermis on saccade adaptation. Brain Res 1401:30-9
Kojima, Yoshiko; Soetedjo, Robijanto; Fuchs, Albert F (2010) Behavior of the oculomotor vermis for five different types of saccade. J Neurophysiol 104:3667-76
Hopp, J Johanna; Fuchs, Albert F (2010) Identifying sites of saccade amplitude plasticity in humans: transfer of adaptation between different types of saccade. Exp Brain Res 202:129-45
Kojima, Yoshiko; Soetedjo, Robijanto; Fuchs, Albert F (2010) Effects of GABA agonist and antagonist injections into the oculomotor vermis on horizontal saccades. Brain Res 1366:93-100
Fuchs, Albert F; Brettler, Sandra; Ling, Leo (2010) Head-free gaze shifts provide further insights into the role of the medial cerebellum in the control of primate saccadic eye movements. J Neurophysiol 103:2158-73
Kojima, Yoshiko; Soetedjo, Robijanto; Fuchs, Albert F (2010) Changes in simple spike activity of some Purkinje cells in the oculomotor vermis during saccade adaptation are appropriate to participate in motor learning. J Neurosci 30:3715-27
Soetedjo, Robijanto; Fuchs, Albert F; Kojima, Yoshiko (2009) Subthreshold activation of the superior colliculus drives saccade motor learning. J Neurosci 29:15213-22
Soetedjo, Robijanto; Kojima, Yoshiko; Fuchs, Albert F (2008) Complex spike activity in the oculomotor vermis of the cerebellum: a vectorial error signal for saccade motor learning? J Neurophysiol 100:1949-66

Showing the most recent 10 out of 73 publications