Oculomotor nerve

The oculomotor nerve, also known as the third cranial nerve, is responsible for controlling most of the eye's movements, including upward, downward, and inward motions. It also helps lift the upper eyelid and controls the size of the pupil to regulate how much light enters the eye. Originating in the brainstem, it travels to the eye muscles, coordinating precise eye movements and focusing. Damage to this nerve can cause double vision, drooping eyelid (ptosis), or difficulty moving the eye, which highlights its crucial role in visual orientation and coordination.