When the subject’s head is
turned to the side of the lesion, the
VOR is deficient and the eyes will
move with the head so that they no
longer fix on the point in the distance.
The patient therefore needs
a refixation saccade just after the
thrust. When the head impulse is
in the direction of the healthy side,
the VOR will maintain the target
on the fovea and no refixation saccade
will be needed.