Various mouth gestures also show affection and desire, such as nuzzling, licking, playful biting and so on. These actions can pleasure the senses by the release of endorphin in the brain that bring two people emotionally closer. Touch, taste and smell sensory nerves are all working to feed pleasure signals to the brain from numerous parts of the body. The lips and tongue have an exceptionally large number of nerves compared to most other areas on the body. The whole body becomes more sensitive. As pheromones are picked up from the partner's skin and hair, strong signals shoot to the old brain limbic system where hormones are released preparing the body for mating and at least temporary bonding.