The term was coined in 1915 by medical officer Charles Myers. At the time it was believed to result from a physical injury to the nervous system during a heavy bombardment or shell attack, later it became evident that men who had not been exposed directly to such fire were just as traumatised.
Despite medical alerts, long term trouble were disregarded as a cowardice and weakness of mind by military leadership. In recent decades and following the 2003 Iraq war, shell shock have been linked to biological brain damages, such as concussions and micro-tearing of the brain tissues.