Flooding stops phobic responses very quickly, this could be because without the option of avoidant behaviour, the patient learns there is nothing to be afraid of. This is called **extinction** - to erase a learned response of fear, the conditioned stimulus (the phobia) must be presented without the unconditioned (the fear of what the phobia will do). The patient can sometimes relax because they are simply exhausted by their fear response. This process can be traumatic, **informed** consent must be received.