Flooding is a behavioural therapy of phobias that is based on the idea of extinction. Rather than exposing a person to their phobic stimulus gradually, a person is exposed to the most frightening situation immediately. For example, a person with a phobia of dogs would be placed in a room with a dog and asked to stroke the dog straight away. With flooding, a person is unable to avoid (negatively reinforce) their phobia and through continuous exposure, anxiety levels decrease (extinguish).