These muscles are innervated by motorneurons that
have electrical activity with a tonic component that
controls the position of the eye, and a phasic component
that controls the velocity of eye movement. Even though
the eye position commands and the eye velocity
commands are linear functions of the firing frequency of
the motorneuron, they are separate sets of commands.
The eye velocity commands are sent along a direct path
from specialized brain formations or fields to the motorneurons.
However, the eye position commands are the
products of the integration of eye velocity commands
sent along an indirect path to a network of neurons that
functions as a neural integrator. It is the output of the
integrator that provides eye position commands to the
motorneurons.