When people think of anger, it is typically regarded as an 'outward expression' and something 'in the moment'. We hear about these expressions in the case of intermittent explosive disorder (IED) only because they are apparent, but what if the anger itself was introspective and lasted for far more than just a moment? Nobody else would be aware, and the sufferer of this condition would carry on regardless until the anger finally subsides, causing all sorts of mental and physical damage. Think of it like a bottle of fizzy drink; if the bottle is shaken you dare not take the cap off in the event it explodes everywhere. Instead, you need to wait until the shaken drink subsides - in which time the drink is ruined. Likewise, the same inward absorbing of rage or resentment is known to cause ailments such as depression, insomnia, digestive problems, ulcers and heart conditions.