Posttraumatic vocal disarticulation

Post-Traumatic Vocal Disarticulation is a Human condition involving the vocal chords of a human being. After a period of extreme stress or trauma, a person diagnosed with this condition is rendered completely unable to speak, even if there is no catastrophic injury to their actual vocal chords. It is unclear if this condition is physical, or if it is merely psychological caused by very traumatic events. However, the words "post-traumatic" may point to it being psychological, as Lucy-B091 was one of the two other surviving SPARTAN-III personnel in her company of 300 after Operation: TORPEDO. The other 298 were all killed in a huge explosion, which shook her terribly. . The Rookie possibly suffers from Post-Traumatic Vocal Disarticulation too, as he never speaks in-game, and he was the only survivor of the Battle of New Jerusalem.