Shell shock is a term that originated during World War I to describe the type of post-traumatic stress disorder (PTSD) that many soldiers experienced during the war, before PTSD was officially recognized. The concept of shell shock was poorly defined during the war, and cases could be interpreted as either a physical or psychological injury, or as a lack of moral fiber. Symptoms of shell shock included fatigue, tremors, confusion, nightmares, impaired sight and hearing, and an inability to function. The term "shell shock" was coined by the soldiers themselves.
Some physicians held the view that shell shock was a result of hidden physical damage to the brain, with the shock waves from bursting shells creating a cerebral lesion that caused the symptoms and could potentially prove fatal. However, others argued that shell shock resulted from psychological trauma, and that it could be cured through cognitive and affective reintegration.
Although the United States’ Department of Veterans Affairs still uses the term shell shock to describe certain aspects of PTSD, it is mostly a historical term, and is often considered to be the signature injury of World War I. Shell shock went from being considered a legitimate physical injury to being a sign of weakness, of both the battalion and the soldiers within it. At least 20% of men developed shell shock during the war, though the figures are murky due to physician reluctance at the time to brand veterans with a psychological diagnosis that could affect disability compensation.
