Journal of Neuroscience, Vol 6, 1976-1982, Copyright © 1986 by Society for Neuroscience
Eye-movement-dependent loss in vision and its time course during vergence
KA Manning
The attenuation of vision that has long been known to accompany saccadic
eye movement has a significant component that is not attributable to visual
masking or image smear, and this suppression of vision is now associated
with nonsaccadic movement. The purpose of the present experiment was to
determine the time course of visual suppression during a vergence eye
movement. Suppression was evaluated psychophysically in human observers by
measuring their loss of sensitivity to a brief, full-field decrement of
light during 6 degrees- 9 degrees convergence. Vergence-related suppression
was similar in total duration and amplitude to saccadic and blink-related
suppression. Since these other forms of oculomotor activity are vastly
different in speed and total duration, it is unlikely that suppression
results directly from the activity itself. Instead, these results support
the hypothesis that a common, more centrally originating, suppression of
vision occurs during eye movements, including saccades, eyeblinks, and
vergence. Thus, while vision during eye movements can often be reduced
through masking and smearing effects, the movement-dependent visual
suppression measured in these experiments is a more generally occurring
event.