Non-genital physiological changes (in the Erotic Brain): 

1. Increased peripheral blood flow.  You might recognize this when the face or chest gets flushed.
2. Bleeding decreases, especially in periphery.
3. Hayfever and sinus congestion decreases.
4. Strength increases.
5. Flexibility increases.
6. Nasal and salivary glands increase production.
7. Movements become more rhythmic, in the pelvis especially.
8. Blood pressure increases.
9. Heart rate increases.
10. Breathing becomes deeper and faster (in early stages).

Genital physiological changes (when we move into our erotic brain):

1. Swelling or Tumescence. Parts of our body swells with blood and some become more rigid. These include … the penis, clitoris, labia & nipple.
2. The lifting and expanding of the back part of the vagina. This is an interesting change that actually allows women to feel the sensation of a “need to be filled”.
3. Rising of the testes. As the arousal increases and men get closer to orgasm the testes lift up to be closer into the body.
4. Genital secretions increase. The vagina lubricates, the penis can leak pre-ejaculate.

Psychological changes: 

1. Inhibitions are reduced.
2. Sensitivity to pain is reduced.
3. Reduction in sensory perception overall. As arousal increases, we tend to become deaf and blind to the outside world. All of the senses decrease.