Citation

Poletti M, Listorti C, Rucci M. J. Neurosci. 2010; 30(33): 11143-11150.

Affiliation

Departments of Psychology and Biomedical Engineering and Program in Neuroscience, Boston University, Boston, Massachusetts 02215.

Copyright

(Copyright © 2010, Society for Neuroscience)

DOI

10.1523/JNEUROSCI.1925-10.2010

PMID

20720121

PMCID

PMC2931276

Abstract

We are normally not aware of the microscopic eye movements that keep the retinal image in motion during visual fixation. In principle, perceptual cancellation of the displacements of the retinal stimulus caused by fixational eye movements could be achieved either by means of motor/proprioceptive information or by inferring eye movements directly from the retinal stimulus. In this study, we examined the mechanisms underlying visual stability during ocular drift, the primary source of retinal image motion during fixation on a stationary scene. By using an accurate system for gaze-contingent display control, we decoupled the eye movements of human observers from the changes in visual input that they normally cause. We show that the visual system relies on the spatiotemporal stimulus on the retina, rather than on extraretinal information, to discard the motion signals resulting from ocular drift. These results have important implications for the establishment of stable visual representations in the brain and argue that failure to visually determine eye drift contributes to well known motion illusions such as autokinesis and induced movement.

Language: en