Saccadic suppression is the reduced visibility that occurs
during saccadic eye movements. Recent psychophysical studies
have suggested that this is due to a reduction in responsiveness
of magnocellular (M), but not parvocellular (P), cells
of the lateral geniculate nucleus. To address this and
other phenomena of responsiveness during saccades, we recorded
from geniculate neurons in the behaving monkey before,
during, and after saccades. Specifically, we measured neuronal
responses to a flashing, whole-field illumination. Contrary
to the prediction, most M neurons showed pronounced enhancement
of visual activity during saccades, whereas such responsiveness
of parvocellular (P) neurons was not significantly affected
by saccades. We also analyzed the extent to which saccades
affected burst firing, which results from activation of
a voltage-dependent Ca2+ conductance. We found
that both M and P cells displayed a significant suppression
of burst firing during saccades. These results do not support
the idea that saccadic suppression has an obvious substrate
in reduced responsiveness of geniculate cells, but this
suppression may be related to an increased visual threshold
for detection associated with reduced burst firing.