Cortical Interactions in the Oculomotor System
M.
Fallah
(York
University)
Previous
neurophysiological
studies
have
demonstrated
that
saccade
curvatures
are
the
result
of
excitatory
and
competitive
interactions
between
potential
saccade
goals
in
the
intermediate
layers
of
the
superior
colliculus
(SCi)
and
frontal
eye
field
(FEF),
whereby
the
resulting
saccade
curvature
is
proportional
to
the
level
of
unresolved
activity
encoding
a
competing
saccade
vector.
This
suggests
that
the
magnitudes
of
saccade
curvature
vary
continuously
along
a
gradient
of
oculomotor
excitation
and
inhibition.
Given
that
top-down
factors
like
task
relevance
are
encoded
by
the
visuomotor
neurons
of
the
oculomotor
system
(reviewed
by
Fecteau
&
Munoz,
2006),
this
predicts
a
functional
relationship
between
saccade
curvature
and
cortical
visual
processing.
I
will
be
presenting
a
series
of
studies
that
investigates
the
featural
and
temporal
factors
affecting
saccadic
encoding,
as
measured
by
saccade
curvatures.
These
studies
provide
increasing
evidence
that
visual
processing
can
be
read
out
of
saccade
metrics.