The Human Sexual Response
There are 4 stages of human sexual response:
Excitement or arousal
This is when parasympathetic nerve impulses produce genital engorgement, vasodilatation and lubrication.
Plateau
This is when parasympathetic nerve impulses produce genital engorgement, vasodilation and lubrication.
Orgasm
This is when sympathetic and somatic nerve impulses cause rhythmical contractions of smooth and skeletal muscle.
Resolution
This is when relaxation takes place with a return to the un-aroused state.