Stimulation of Nipples - Physiological Response

Physiological Response

Stimulation of nipples may result in nipple erection due to the contraction of smooth muscle under the control of the autonomic nervous system and are a product of the pilomotor reflex which causes goose bumps. Nipple erection can also be caused by a mild tactile stimulation or as a response to cold temperature in both males and females. Nipple erection may also result during sexual arousal in females and males, or during breastfeeding. Both are caused by the release of oxytocin.

The stimulation of a woman's nipples promotes the production and release of oxytocin and prolactin. During the stimulation of the nipples, large amounts of oxytocin are released, which would normally prepare the breast for breastfeeding. Besides creating maternal feelings in a woman, it also decreases her anxiety, increases human bonding and trust.

The release of oxytocin can also result in a female's sexual arousal, with the resulting physiological effects including the erection of the nipples. An erection of the nipples makes them even more sensitive to touch. An orgasm by nipple stimulation can be achieved in some women. A 2011 study using magnetic resonance imaging has shown that the area of the sensory cortex in a woman's brain associated with the genitals, is aroused by stimulating her nipples.

Prolactin produces sexual gratification after sexual activity. Prolactin represses the effect of dopamine, which is responsible for sexual arousal, and is thought to cause the sexual refractory period following orgasm during which the individual (typically a male) does not desire any further sexual stimulation. During this period, the nipples can become extremely sensitive to touch and further stimulation can be painful. The amount of prolactin can be an indicator for the amount of sexual satisfaction and relaxation. Unusually high amounts are suspected to be responsible for impotence and loss of libido (see hyperprolactinemia symptoms).