The sixth out of twelve cranial nerves, the abducens nerve controls the lateral rectus muscle - this means that the action of this nerve controls each eye's ability to look laterally (away from the midline).

The abducens nerve emerges from the brainstem between the pons and the medulla, and exits the skull through the superior orbital fissure (one of the holes in the skull behind the eye).

Looking for a 6th nerve palsy is a good screening sign in children with suspected meningitis. As the abducens emerges near the bottom of the brain, it is often the first nerve compressed when there is any rise in intracranial pressure.