On the Notion of Doll's Eyes-Reply

In Reply.  —Professor Van den Bergh's comments are most appreciated.The oculocephalic reflex (OR) is abolished by lesions of the caudal pontine and rostral medullary tegmentum because of disruption of the reflex arc at the level of the vestibular nuclei (for both vertical and horizontal ORs) or the horizontal gaze apparatus (for horizontal OR). Bilateral internuclear ophthalmoplegia interrupts only the vertical OR and medial rectus (MR) component of the horizontal gaze OR. Midbrain lesions also eliminate the vertical OR and the MR component of the horizontal OR.¹ Unilateral lesions of the medial longitudinal fasciculus have not been reported to affect the vertical OR but do eliminate the ipsilateral MR component of the horizontal OR. The modifiers inhibited, disinhibited, and absent [abolished] succinctly describe all possible clinical situations, although elaboration of partial responses may be necessary to verbally convey the clinical observation (eg, disinhibited horizontal OR with absent MR bilaterally and absent