Conjunctival Reflex

Conjunctival reflex is caused by stroking irritation of the conjunctival membrane of the eyeball and is expressed by closure of the eyelid. Method of elicitation: the eyelid should be widely opened, the eye is turned to the opposite side for maximum exposure of the conjunctiva, irritation is applied by touching with a rolled-up piece of paper. The afferent arc of the reflex is the superior branch of the trigeminal nerve, the efferent arc is the superior branch of the facial nerve, the reflex arc is closed in the area of the pontine tegmentum. The conjunctival reflex in normal conditions is characterized by great constancy, although its intensity, like that of other reflexes from mucous membranes, varies within very wide limits. Apparently, it can sometimes disappear in cases of hysteria (especially on the side of hysterical hemianesthesia), but most often its disappearance indicates organic damage to the corresponding reflex arc, i.e., either damage to the superior branch of the trigeminal nerve, or damage to the superior branch of the facial nerve, or finally an organic process in the caudal part of the pontine tegmentum.