'7' is the hook that closes the eye; 'III' is the pillar that opens the eye.
CN VII lesions above the nucleus spare the forehead. For this reason, stroke victims usually don't need their eyes sutured shut. (Contrast: Bell's palsy, a lesion below the nucleus, takes out the entire half of the face.)
Romberg's test
The cerebellum integrates vestibular, proprioceptive, and ocular input to maintain balance (you need TWO out of the three). A positive Romberg's occurs when patient is stable with eyes OPEN, but wobbles with them closed. You need additional testing to figure out whether vestibular or proprioceptive deficit is to blame. (Proprioceptive deficit: patient can't tell if you are moving toe up or down.)
A pure deficit in cerebellum causing ataxia does not give positive Romberg's, as the patient wobbles even with eyes open.
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