Flooding is based on similar principles as SD, in that it also views, phobias as being learnt through association and it can therefore also be unlearnt.
Flooding also works on the principle of reciprocal inhibition, that we cannot feel two opposing emotions at the same time (i.e. anxiety and relaxation).
Flooding therefore aims to replace the feelings of fear with feeling of relaxation.
However during flooding rather than gradually exposing the individual to the feared stimuli, the individual is exposed to it in one long session and sometimes this is enough to cure a phobia.
This session continues until the patient is
simultaneously confronting the fear of heights, snakes, and the dark.
fully relaxed.
During flooding the phobic stimuli is experienced without the UCS and so the patient stops feeling the CR (the fear) and it is replaced with a new CR (relaxation).