An alteration of consciousness that is characterized by an individual with severe brain damage being in a state of partial arousal rather than true awareness. After four weeks in a vegetative state, the patient is classified as being in a persistent vegetative state. After three months in the US and six months in the UK, the diagnosis is classified as a permanent vegetative state after a non-traumatic brain injury, or, one year after a traumatic injury. [ url:https://en.wikipedia.org/wiki/Persistent_vegetative_state ]