Provide a clear path for ambulation without obstacles -cranial nerve ii is the optic nerve, which governs vision. the nurse can provide safety for the visually impaired client by clearing the path of obstacles when ambulating. testing the shower water temperature would be useful if there were an impairment of peripheral nerves. speaking loudly may help overcome a deficit of cranial nerve viii (vestibulocochlear). cranial nerve vii (facial) and ix (glossopharyngeal) control taste from the anterior two thirds and posterior third of the tongue, respectively.