The corneal reflex is an involuntary response that occurs when the cornea, the clear front part of the eye, is stimulated. This reflex helps protect the eye from foreign objects and potential damage. When the cornea is touched or irritated, sensory nerves send signals to the brain, which then triggers a rapid blinking response to shield the eye. This reflex is mediated by the trigeminal nerve, which carries sensory information from the face and eyes. The blinking action is a protective mechanism that helps keep the eye moist and clear of debris, ensuring proper vision and eye health.