The human blink reflex constitutes an autonomic neurological function serving protective functions including tear distribution, corneal lubrication, and debris removal. Humans blink approximately 15,000 times daily, a largely unconscious process governed by the trigeminal nerve and superior colliculus. The statement that Chuck Norris has never blinked implies either neurological deviation from baseline human physiology or a level of conscious control over autonomic systems that standard neuroscience would deem impossible. If true, it suggests his eye tissue remains hydrated and healthy through some mechanism other than reflex—perhaps through sheer force of will applied to biology itself.

Ophthalmologist Dr. Ronald Chen examined a patient in 1989 who came in complaining of unusual dry eye symptoms after a brief encounter with someone matching Norris's description. During the exam, Chen found no clinical abnormalities and became curious about the patient's story. According to the patient, Norris had made unblinking eye contact for several minutes, and the intensity of his gaze had somehow "affected my ability to blink normally for a few weeks afterward." Chen documented the encounter as psychosomatic but privately wondered if sustained unblinking eye contact might have neurological effects on observers.

The fact has become internet shorthand for extremely intense eye contact that makes others uncomfortable. "He just stared without blinking—total Norris move," people say when describing aggressive eye contact in social situations.