Female Sexual Nervous System

Introduction

Female sexual arousal and orgasm require an enormous amount of communication between multiple organs within the body. This communication is necessary so the mind and body can maintain control over themselves and work in harmony. The communication takes place within the nervous system utilizing electrical and chemical messengers. These messengers follow paths within the body called nerves. The brain and spinal cord make up the central nervous system and they communicate to the individual organs and systems of the body by means of peripheral nerves. Some nerves tell the body to do things while others sense what the body is experiencing. Together they control our body, and as a result our response to sexual stimulation.

Our nervous system is much like our transportation system, which in part is made up of roadways, railways, and waterways. In some cases we can get to a destination using only one route or means of transportation, say by car on Route 6, but we can get to other destinations by car, train, and boat. The vehicle or means of transportation we choose determines the route we can take to get to our destination, if we can ultimately reach our destination, and how quickly we can get there. The means of transportation may also determine what we can do when we get to our destination, what we can take with us. These same principles apply to the communication pathways within our body and the messengers that follow them. The three communication networks of the body are the somatic, sympathetic, and parasympathetic nervous systems. Each of these networks allow a specific type of communication and control, and each organ of the body is connected to one or more of them.

Awareness and Control

Somatic sensory nerves are connected to our skin and autonomic sensory nerves are connected to our internal organs. We feel touch, vibration, temperature, pressure, and pain when somatic nerves are stimulated but we may only feel pressure or pain when autonomic nerves are stimulated. Somatic nerves also connect to muscles we can voluntarily control and autonomic nerves to muscles we cannot voluntarily control. When some of the sensory nerves are stimulated we "feel" it but when others are stimulated we do not, but our body responds without our knowing; our body responds on a subconscious level. We generally know when our skin is touched but a woman may not feel her partner touching the internal areas of her vagina, or feels only pressure or pain. In some cases we become aware of this "subconscious" communication, which is most often in the form of pain or pressure associated with our internal organs. Women are not usually aware of their uterus and cannot "feel" it, but during menstruation they may become acutely aware of when it contracts to expel menstrual fluid. Women also cannot control their uterus and voluntarily contract or relax its muscles. It appears our sensitivity to and awareness of stimulation on a conscious and subconscious level is very much an individual experience, and this may depend on the situation in which the stimulation occurs, and the type of stimulation. Sometimes we feel pain in a location other than in which the pain actually originates, which is called referred pain, and this involves the internal organs, but we feel it on the surface of the skin.

The Unique Individual

Each person's network of nerves and chemical and electrical messengers is unique to them. There are similarities amongst a group of individuals but each individual's network of nerves and messengers is as unique as their fingerprints. The female sexual nervous system is largely a mystery to the medical community and the uniqueness of the individual adds to this mystery. Add in the unique experiences of an individual woman and the resulting psychological makeup, i.e. programming of her brain, and we can see why there is such a vast amount of diversity regarding female sexuality. A woman's individual medical history will also affect her nervous system. Since each woman is unique we must expect her to have unique responses to sexual stimulation. While we like to make generalizations, doing so is very dangerous to the individual.

Physical and Mental Sexual Arousal

Sexual arousal may occur as a result of mental and/or physical stimulation. This means the arousal can originate in the brain (psychogenic) or in the body (neurogenic). When a woman sees her partner in the appropriate circumstances her brain will find these visual images sexually stimulating. This causes her brain to send messengers throughout her body to prepare her physically for the possible forthcoming sexual activity. Some messengers go to the heart to increase the heart rate, others go to the pelvic organs to increase the amount of blood engorgement. These visual images may initiate sexual thoughts and communication within the brain resulting in increased mental and physical arousal, as may the awareness of her increasing physical arousal. The mind/body connection should serve to increase the level of sexual arousal, as long as the sexual stimulation continues.

The sexual arousal process can also begin within the body. A woman's tight fitting pants might stimulate her vulva and clitoris resulting in physical sexual arousal involving her pelvic and genital organs. As a result of this physical arousal messengers may be sent to the brain that make her consciously aware of this physical arousal. If her brain receives and processes these messengers she may be motivated to seek out her sexual partner or to masturbate, because the arousal feels pleasurable, it creates a desire for physical pleasure, or awakens innate sexual desire. Innate or hormonally induced sexual desire may also trigger sexual arousal in the mind and body without any sensory input to the mind and body, as in the case of female wet dreams, which occur without stimulation of the five senses. While some women are able to experience orgasm as a result of visual images or thought alone, mental sexual arousal and orgasm are always associated with physical changes in the body, indicating the resulting arousal and orgasms are not "imagined."

Reflex Responses

Some functions of the body occur automatically without any influence or input from the brain. When we touch a hot surface we automatically pull our body away, as a protective mechanism. The brain is not involved in this response, as it must occur very quickly to protect our body from severe injury. When we become scared or anxious our heart rate increases rapidly so we are physically capable of running away, protecting ourselves. When we become sexually aroused or experience sexually arousing events many changes within our body occur automatically without the brain or our conscious self having control over them.

When the vulva is stimulated this causes messengers to be sent to the spinal cord and the brain. These sensory messengers cause the spinal cord to automatically send control messengers back to the vulva and pelvic organs requesting the physical changes associated with sexual arousal, i.e. blood engorgement and vaginal lubrication. This occurs without any input from the brain. This automatic response to physical stimulation of the vulva is called a "reflex" response, or reflex arc. It is a hard wired response and is not something women have control over.

This physical sexual arousal may occur without a woman being consciously aware of it or wanting it. This is why women experience physical sexual arousal in situations in which they do not desire it, and in which they may consider it inappropriate, such as during a gynecological examination and sexual abuse. Since her brain does not need to be involved in this process she may experience physical sexual arousal without being aware of it on a conscious or mental level, and this may influence her perception of arousal. During partnered sex a woman's partner may be aware of her reflex arousal even if she isn't. This is why women with injuries or diseases that affect their nervous system can experience physical sexual arousal that involves their pelvic organs even though they cannot feel it and aren't mentally aware of it; the communication pathways of the mind and body are disconnected, but functional above and below the point of injury or disease. Even in situations where there isn't damage to the body the mind may block awareness of sexual arousal, or the brain is simply overwhelmed by daily life or the sexual situation and cannot process this information; it is overloaded with information.

Pathways to Erogenous Zones

In a survey on this website women have indicated the areas of their body that are sensitive to sexual touch, and that stimulation of some areas of their body increases their level of sexual arousal, at least in appropriate circumstances. These areas of the body are commonly called erogenous zones. Stimulation of erogenous zones results in physical pleasure, which we arbitrarily define as sexual pleasure if it results in a sexual response, i.e. sexual arousal. They are connected to the central nervous system by specific pathways or nerves.

Shown below is a table that lists the nerves that are connected to common erogenous zones. They are listed in the order that women report they are likely to be sensitive to sexual touch, with the areas with the greatest likelihood listed first. Since each woman is unique she is likely to have her own unique map of erogenous zones, and many women may find their body is different from what is described. Each woman and her partner need to explore and discover her own erogenous zones; a woman's erogenous zones may vary depending on whether it is her or her partner's touch that is stimulating them, or the means of stimulation, i.e. fingers, mouth, vibrator, etc.

The detailed information about the nervous pathways is provided since injuries and diseases may damage or sever the pathways resulting in impaired or absent erogenous zones. Conversely, if a woman knows which pathways are not impaired she may want to know which potential erogenous zones to explore and develop if she seeks to experience sexual arousal and orgasm.

A visual map of the innervation of the skin is called a dermatome map. Your can see some on the web sites linked to below:

Dermatomes of the Lower Extremities

Dermatome Map

Dermatomic Area

You can learn about dermatomes and myotomes at the following website:

Dermatomes And Myotomes - An Overview

Note: A "plexus" is a network of nerves that is similar to a major highway interchange within a large city. While a highway interchange can be very confusing to drive through you can still get from point A to point B. You often have to pass through a major interchange to get to your destination while driving, and the same is true of your electrical and chemical messengers as they travel about your nervous system.

Body Area	Cranial & Spinal Nerves	Peripheral Nerves	Function
Clitoris	S2, S3, S4	Sacral Plexus: Pudendal nerve Dorsal nerve of clitoris Perineal nerve	Skin on shaft of the clitoris and the surface of the clitoral glans. Senses pain, temperature, touch, and pressure. Controls blood vessels, and smooth muscles of skin.
Clitoris	S2, S3, S4	Uterovaginal nerve plexus: Cavernous nerves	Involuntary control and autonomic sensation; i.e. sense pain and pressure. May provide an indication of pressure when the erectile structures of the clitoris and vulva are engorged. Controls blood flow to the erectile structures of the clitoris.
Nipple/Areola	T2, T3, T4, T5 (1)	Intercostal nerves: Anterior and lateral cutaneous (skin) branches	Senses pain, temperature, touch, and pressure. Controls blood vessels, and involuntary muscles of nipples.
Neck	C2, C3, C4	Great auricular nerve Transverse cervical nerve Supraclavicular nerves Lesser occipital nerve	Senses pain, temperature, touch, and pressure.
Mouth	CN V2	Maxillary Nerve Infraorbital nerve	Senses pain, temperature, touch, and pressure. Controls blood vessels, and smooth muscles of skin.
Mouth	CN V3	Mandibular Nerve Mental nerve
Vagina	S2, S3, S4	Sacral Plexus: Pudendal nerve Perineal nerve	Outer 1/5 to 1/4 of vagina. Sensitive to touch and temperature. Voluntary control of some pelvic muscles.
Vagina	S2, S3, S4	Inferior Hypogastric (Pelvic) Plexus and Uterovaginal nerve plexus	Inner 4/5 to 3/4 of vagina. Involuntary control and autonomic sensation; i.e. sense pain and pressure.
Inner Labia	(2)
Thighs	L1, L2, L3, L4	Lumbar Plexus: Genitofemoral Obturator Lateral cutaneous nerve Femoral nerve	Skin on front and sides of the thighs. Senses pain, temperature, touch, and pressure. Controls blood vessels, and smooth muscles of skin.
Thighs	S2, S3, S4	Sacral Plexus: Posterior cutaneous nerve of thigh	Skin on back of the thighs. Senses pain, temperature, touch, and pressure. Controls blood vessels, and smooth muscles of skin.
Breasts	C3, C4 (1)	Supraclavicular nerves	Senses pain, temperature, touch, and pressure. Controls blood vessels, and smooth muscles of skin and nipples
Breasts	T1, T2, T3, T4, T5, T6, T7 (1)	Intercostal nerves: Anterior and lateral cutaneous (skin) branches
Outer Labia	L1, L2	Lumbar Plexus: Ilioinguinal nerves Genitofemoral nerves Anterior labial nerves	Front portion of outer labia. Senses pain, temperature, touch, and pressure. The genitofemoral nerve controls the cremaster muscle
Outer Labia	S1, S2, S3, S4	Sacral Plexus: Posterior cutaneous nerve of thigh Pudendal nerve Perineal nerve Posterior labial nerves	Back portion of outer labia. Senses pain, temperature, touch, and pressure.
Pubic Mound	L1, L2	Lumbar Plexus: Ilioinguinal Anterior labial nerves Genitofemoral	Senses pain, temperature, touch, and pressure. The genitofemoral nerve controls the cremaster muscle
Back	C2 - C8, T1 - T12 L1 - L5 S1 - S5	Spinal Nerves	Each spinal nerve supplies a small section of the neck, back, and buttocks. The nerves listed are for the neck, back, and buttocks, as there is no clear demarcation between these areas of the body. These nerves sense pain, temperature, touch, and pressure.
Hips	T12, L2, L3, L4, L5	Subcostal nerve Iliohypogastric nerve Lateral cutaneous nerve of thigh	Senses pain, temperature, touch, and pressure.
Buttocks	L1, L2, L3 S1, S2, S3	Clunial nerves	Senses pain, temperature, touch, and pressure.
Sides	T1 - T12	Spinal Nerves	Senses pain, temperature, touch, and pressure.
Perineum	S4	Sacral Plexus: Pudendal nerve Perineal nerve	Senses pain, temperature, touch, and pressure.

Body Area	Spinal Nerves	Peripheral Nerves	Function
Bladder	T11, T12, L1, L2, L3 S2, S3, S4	Hypogastric Plexus, Inferior Hypogastric (Pelvic) Plexus, Uterovaginal nerve plexus	Involuntary control and autonomic sensation; i.e. sense pain and pressure.
Bladder	S2, S3, S4	Sacral Plexus: Pudendal nerve	Voluntary control and somatic sensation.
Urethra (2)	T11, T12, L1, L2, L3 S2, S3, S4	Inferior Hypogastric (Pelvic) Plexus,Uterovaginal nerve plexus	Involuntary control and autonomic sensation; i.e. sense pain and pressure.
Urethra (2)	S2, S3, S4	Sacral Plexus: Pudendal nerve	Voluntary control and somatic sensation
Anus	S2, S3, S4	Sacral Plexus: Pudendal nerve Inferior anal nerves	Voluntary control and somatic sensation
Rectum	T12, L1, L2	Inferior Hypogastric (Pelvic) Plexus Uterovaginal nerve plexus Rectal Plexus	Involuntary control and autonomic sensation; i.e. sense pain and pressure.
Rectum	S2, S3, S4	Sacral Plexus: Pudendal nerve Inferior anal nerves	Voluntary control and somatic sensation
Cervix	CN X	Vagus nerve	Involuntary control and autonomic sensation; i.e. sense pain and pressure. Some women are more sensitive to stimulation of their cervix than others, and cervical stimulation results in orgasm in some.
Cervix	S2, S3, S4	Inferior Hypogastric (Pelvic) Plexus and Uterovaginal plexus	Involuntary control and autonomic sensation; i.e. sense pain and pressure.
Uterus	T12, L1, L2 S2, S3, S4	Superior Hypogastic Plexus, Inferior Hypogastric (Pelvic) Plexus, Uterovaginal plexus	Involuntary control and autonomic sensation; i.e. sense pain and pressure.
Female Prostate Gland (1) (2)	T11, T12, L1, L2, L3 S2, S3, S4	Inferior Hypogastric (Pelvic) Plexus, Uterovaginal nerve plexus, Prostatic plexus	Involuntary control and autonomic sensation; i.e. sense pain.

Notes:

(1) Presumed, based on the male prostate gland. Some references say these nerves do not exist in women, but since women have a functional prostate gland this is unlikely to be true.

(2) The female urethra and prostate gland are part of the front wall of the vagina and are not separate and distinct organs. The nerves for these three "organs" may then occupy the same space and result in complex innervation. This may explain why the front wall of the vagina is often the most sensitive portion of the vagina, and be the reason why some women have a G-Spot and others feel a need to urinate when their vagina is stimulated.

Nerves of the Vulva & Clitoris

The quotated information in this section is from the book The Clitoris by Thomas P Lowry, M.D. and Thea Snyder Lowry, M.A., copyright 1976 Warren H. Green, Inc.

"The clitoris has somatic sensory, somatic motor, visceral motor (autonomic), and vasosensory components. The pudendal nerve, a mixed somatic nerve, and the hypogastric autonomic plexus serve perineum and vulvar structures."

This means the clitoris has nerves that transmit the sense of touch to the spinal cord and brain, that there are muscles that you can voluntarily control and those you cannot control, and nerves that monitor the state of the blood vessels, i.e. blood flow and pressure. The nerve supply is very complex, a lot goes on that women aren't necessarily consciously aware of, and that they don't feel happening or have control over. The hypogastric network provides nerves to the organs we don't have voluntary control over, like the erectile structures of the clitoris and inner labia, and the involuntary muscles of the vagina, uterus, urethra, and bladder.

"General sensation to the skin of glans, prepuce, and body passes in the pudendal nerve to lumbosacral plexus and to anterior rami of spinal nerves S.2-4, via anterior sacral foramina. Probably many vasosensory fibers are also conveyed, though most return to cord in autonomic nerves. Somatic motor fibers are conveyed to perineal muscles, arising in cord anterior gray S.2-4."

This means the sense of touch for the clitoris is transmitted to the spinal cord through the pudendal nerve through a network of nerves near and joining with the spinal cord in the lower back. Some of the nerves that monitor the blood vessels pass through the pudendal nerve, but most pass through autonomic nerves to the spinal cord. (A nerve is much like a large telephone cable having hundreds of wires that allow hundreds of conversations to occur at the same time. Each "wire" in a nerve is called a neuron.) The pelvic muscles that you can voluntarily control, like when doing Kegel exercises, are controlled by nerves that originate in the same area of the spinal cord. The pudendal nerve and its branches that innervate the vulva are shown in the following illustrations. There are two pudendal nerves, and each is mirrored on the left and right sides of the body.

From the book: For Women Only
Copyright 2001 by Jennifer Berman, M.D.,
and Laura Berman, Ph.D..
Illustration Copyright Lori A. Messenger, CMI

From the book: A New View of a Woman's Body
Copyright 1981, The Federation of Feminist Women's Health Centers
Illustration By: Suzann Gage, L Ac, RNC, NP

"Erectile bodies have sympathetic and parasympathetic (visceral motor, autonomic), and vasosensory (visceral sensory) innervation, terminating profusely in the specialized smooth muscle wall of the arteries and veins, and the semi-erectile blood spaces of labial and vestibular tissues. These autonomics arise from thoracolumbar outflow [L.1-2(3)], and craniosacral outflow (S.2-4) to enter the inferior hypogastric nerve plexus, and reach the vulva and perineum by cavernous nerves and the pudendal nerves."

The areas of the vulva and clitoris that become engorged with blood during sexual arousal are controlled by nerves we don't have voluntary or direct control over. They are controlled by the sympathetic and parasympathetic nervous systems. These nerves sense the state of the erectile organs and control the smooth muscles (involuntary muscles) within the walls of the blood vessels and regulate blood flow and engorgement. These autonomic nerves also control involuntary muscles in organs like the vagina, uterus, bladder, and urethra. These nerves originate in the brain and lower back, but primarily in the area of the lower back; the main exception being the vagus nerve that innervates the cervix and uterus. The cavernous nerves supply the crura of the clitoris, the internal erectile portion of the clitoris, and control clitoral engorgement; how firm or erect it is. The sympathetic and parasympathetic nervous systems also play an important role in the experience of orgasm, namely the rhythmic contraction of the involuntary muscles during orgasm.


From the book: For Women Only Copyright 2001 by Jennifer Berman, M.D., and Laura Berman, Ph.D.. Illustration Copyright Lori A. Messenger, CMI	From the book: A New View of a Woman's Body Copyright 1981, The Federation of Feminist Women's Health Centers Illustration By: Suzann Gage, L Ac, RNC, NP