Instruct: Given a question, retrieve relevant passages that answer the question.
Query: Is it normal to not experience sexual arousal?
However, when a person fails to be aroused in a situation that would normally produce arousal and the lack of arousal is persistent, it may be due to a sexual arousal disorder or hypoactive sexual desire disorder. There are many reasons why a person fails to be aroused, including a mental disorder, such as depression, drug use, or a medical or physical condition. The lack of sexual arousal may be due to a general lack of sexual desire or due to a lack of sexual desire for the current partner. A person may always have had no or low sexual desire or the lack of desire may have been acquired during the person's life. There are also complex philosophical and psychological issues surrounding sexuality. Attitudes towards life, death, childbirth, one's parents, friends, family, contemporary society, the human race in general, and particularly one's place in the world play a substantive role in determining how a person will respond in any given sexual situation.
This table shows the sex differences in erogenous zones and includes the top ten most arousing areas for both sexes. Each body part was rated out of ten for how arousing it is when touched. Apart from body parts exclusive to one gender such as the penis or clitoris, many of the erogenous zones are similar and contain lots of nerve endings. They suggested also that women experience more areas of greater arousal than men do. 
The excitation-transfer theory states that existing arousal in the body can be transformed into another type of arousal. For example, sometimes people can be sexually stimulated from residual arousal arising from something such as exercise, being transformed into another type of arousal such as sexual arousal. In one study participants performed some physical exercise and at different stages of recovery had to watch an erotic film and rate how aroused it made them feel. They found that participants who were still experiencing excitatory residues from the exercise rated the film as more arousing than those who had fully recovered from the exercise. This suggests that the remaining arousal from the exercise was being transformed into sexual arousal without any external stimulation.
Psychological sexual arousal involves appraisal and evaluation of a stimulus, categorization of a stimulus as sexual, and an affective response.[16] The combination of cognitive and physiological states elicits psychological sexual arousal.[16][17] Some suggest that psychological sexual arousal results from an interaction of cognitive and experiential factors, such as affective state, previous experience, and current social context.[18]
Olfactory information is critical to human sexual behavior. One study investigating olfactory sexual stimulation found that men experience sexual arousal in response to a female perfume. Individuals rated odourant stimulation and perceived sexual arousal. They also had functional MRI scans taken during the experiment. The results showed that olfactory stimulation with women's perfume produces activation of specific brain areas associated with sexual arousal in men.
Female arousal is complex, as evidenced by the findings that women’s reported feelings of sexual arousal have not been found to correlate with physiological genital arousal, and that for many women there is no reported distinction between their experiences of sexual desire and arousal.
Sexual arousal for most people is a positive experience and an aspect of their sexuality, and is often sought. A person can normally control how they will respond to arousal. They will normally know what things or situations are potentially stimulating, and may at their leisure decide to either create or avoid these situations. Similarly, a person's sexual partner will normally also know his or her partner's erotic stimuli and turn-offs. Some people feel embarrassed by sexual arousal and some are sexually inhibited. Some people do not feel aroused on every occasion that they are exposed to erotic stimuli, nor act in a sexual way on every arousal. A person can take an active part in a sexual activity without sexual arousal. These situations are considered normal, but depend on the maturity, age, culture and other factors influencing the person.
Research suggests that cognitive factors like sexual motivation, perceived gender role expectations, and sexual attitudes play important roles in women's self-reported levels of sexual arousal.[18] In her alternative model of sexual response, Basson[25][26] suggests that women's need for intimacy prompts them to engage with sexual stimuli, which leads to an experience of sexual desire and psychological sexual arousal. Psychological sexual arousal also has an effect on physiological mechanisms; Goldey and van Anders[27] showed that sexual cognitions impact hormone levels in women, such that sexual thoughts result in a rapid increase in testosterone in women who were not using hormonal contraception. In terms of brain activation, researchers have suggested that amygdala responses are not solely determined by level of self-reported sexual arousal; Hamann and colleagues[24] found that women self-reported higher sexual arousal than men, but experienced lower levels of amygdala responses.
Female sexual arousal disorder (FSAD) is a disorder characterized by a persistent or recurrent inability to attain sexual arousal or to maintain arousal until the completion of a sexual activity. The diagnosis can also refer to an inadequate lubrication-swelling response normally present during arousal and sexual activity. The condition should be distinguished from a general loss of interest in sexual activity and from other sexual dysfunctions, such as the orgasmic disorder (anorgasmia) and hypoactive sexual desire disorder, which is characterized as a lack or absence of sexual fantasies and desire for sexual activity for some period of time.
In 2000, Rosemary Basson presented an alternative model to the human sexual response cycle that is specific to women’s sexual response.[30] She argues that gender differences in sex drive, sexual motivation, sexual concordance, and capacity for orgasm underlie the need for an alternative model of sexual response. While the human sexual response cycle begins with desire, followed by arousal, orgasm, and finally resolution, Basson’s[26] alternative model is circular and begins with women feeling a need for intimacy, which leads her to seek out and be receptive to sexual stimuli; women then feel sexual arousal, in addition to sexual desire. The cycle results in an enhanced feeling of intimacy. Basson emphasizes the idea that a lack of spontaneous desire should not be taken as an indication of female sexual dysfunction; many women experience sexual arousal and responsive desire simultaneously when they are engaged in sexual activity.[30]
Thomas Nagel proposes that only sexual interactions with mutual sexual arousal are natural to human sexuality. Perverted sexual encounters or events would be those in which this reciprocal arousal is absent, and in which a person remains fully a subject of the sexual experience or fully an object.
A 28-item questionnaire that psychometrically evaluates the level of arousability produced by sexual experiences, whereas "SAI-E Sexual Arousability Inventory Expanded" measures anxiety and arousability and it is meant for men and women regardless their psychosexual orientation.
Human sexual activity, human sexual practice or human sexual behaviour is the manner in which humans experience and express their sexuality. People engage in a variety of sexual acts, ranging from activities done alone (e.g., masturbation) to acts with another person (e.g., sexual intercourse, non-penetrative sex, oral sex, etc.) in varying patterns of frequency, for a wide variety of reasons. Sexual activity usually results in sexual arousal and physiological changes in the aroused person, some of which are pronounced while others are more subtle. Sexual activity may also include conduct and activities which are intended to arouse the sexual interest of another or enhance the sex life of another, such as strategies to find or attract partners (courtship and display behaviour), or personal interactions between individuals (for instance, foreplay or BDSM). Sexual activity may follow sexual arousal.
Sexual arousal disorder is characterized by a lack or absence of sexual fantasies and desire for sexual activity in a situation that would normally produce sexual arousal, or the inability to attain or maintain typical responses to sexual arousal. The disorder is found in the DSM-IV. The condition should not be confused with a sexual desire disorder.
Research conducted by Donald G. Dutton and Arthur P. Aron in the 1970s aimed to find the relation between sexual attraction and high anxiety conditions. In doing so, 85 male participants were contacted by an attractive female interviewer at either a fear-arousing suspension bridge or a normal bridge. Conclusively, it was shown that the male participants who were asked to by the female interviewer to perform the thematic apperception test (TAT) on the fear-arousing bridge, wrote more sexual content in the stories and attempted, with greater effort, to contact the interviewer after the experiment than those participants who performed the TAT on the normal bridge. In another test, a male participant, chosen from a group of 80, was given anticipated shocks. With him was an attractive female confederate, who was also being shocked. The experiment showed that the male's sexual imagery in the TAT was much higher when self shock was anticipated and not when the female confederate shock was anticipated.
In general and across cultures, public indications of sexual arousal are commonly regarded as embarrassing, both to the person aroused and the onlooker, and for this reason those parts of the human body that would indicate arousal are normally covered. Arousal is most evidently indicated by the sex organs and women's breasts, which are routinely covered, even when other parts of the body may be freely uncovered. Yet the nudity taboo may have meanings deeper than the immediate possibility of sexual arousal, for example, in the cumulative weight of tradition and habit. Clothing also expresses and symbolizes authority, and more general norms and values besides those of a sexual nature.
One way to study sexual arousal in women and men is to conduct sexual psychophysiological research in a laboratory setting. This field of research looks at physical sexual responses in addition to mental and emotional experiences of sexual arousal.[38]
Sexually induced sneezing is a phenomenon characterized by sneezing during orgasm or sexual arousal.
The person experiences sneezing as a result of sexual thoughts, arousal, intercourse, or orgasm. 
Auditory stimulants may also serve to intensify sexual arousal and the experience of pleasure. Making sounds during sexual arousal and sexual activity is widespread among primates and humans. These include sighs, moans, strong expirations and inspirations, increased breathing rate and occasionally, at orgasm, screams of ecstasy. Many of these sounds are highly exciting to men and women, and act as strong reinforcers of sexual arousal, creating a powerful positive feedback effect. Thus, copulatory vocalisations are likely to serve mutual sexual stimulation for mating partners.
Though the traditional model of sexual response was founded on the belief that sexual thoughts and fantasies are normally sufficient to initiate arousal, which should then lead to orgasm and end in a resolution phase, “sexual hunger” in the form of initial arousal is not the sole reason women report for being sexual. A lack of spontaneous desire is not necessarily indicative of sexual dysfunction. Women often express a desire to engage in sexual intimacy as a means to get closer to their partners, to increase emotional closeness, commitment, tenderness, tolerance and to express their appreciation for their partner both physically and/or emotionally. Women are more likely to experience spontaneous desire early in relationships, midcycle, after a partner has been absent emotionally or physically, however, women may also follow no particular pattern in their experiences of spontaneous sexual desire.
Category-specificity refers to a person showing sexual arousal to the categories of people they prefer to have sex with. Sexual arousal studies involving category-specificity look at genital responses (physiological changes), as well as subjective responses (what people report their arousal levels to be). Category-specific sexual arousal is more commonly found amongst men than women.[51][52] Heterosexual men experience much higher genital and subjective arousal to women than to men. This pattern is reversed for homosexual men.[53]
The body's physical arousal response (vaginal lubrication and engorgement of the clitoris in women and erection in men) occurs due to two separate pathways which normally work together: psychogenic and reflex. Arousal due to fantasies, visual input, or other mental stimulation is a psychogenic sexual experience, and arousal resulting from physical contact to the genital area is reflexogenic. In psychogenic arousal, messages travel from the brain via the spinal cord to the nerves in the genital area. The psychogenic pathway is served by the spinal cord at levels T11–L2. Thus people injured above the level of the T11 vertebra do not usually experience psychogenic erection or vaginal lubrication, but those with an injury below T12 can. Even without these physical responses, people with SCI often feel aroused, just as uninjured people do. The ability to feel the sensation of a pinprick and light touch in the dermatomes for T11–L2 predicts how well the ability to have psychogenic arousal is preserved in both sexes. Input from the psychogenic pathway is sympathetic, and most of the time it sends inhibitory signals that prevent the physical arousal response; in response to sexual stimulation, excitatory signals are increased and inhibition is reduced. Removing the inhibition that is normally present allows the spinal reflexes that trigger the arousal response to take effect.
Some researchers found that men are more aroused by sexual media than are women, especially in response to sexually violent or dehumanizing materials. Also, sexual violence may only appeal to sex offenders and other violence-prone men and even to "normal" men if the victim is portrayed as being aroused by the assault. Slides or verbal descriptions of coercive sex are more appealing to sexually coercive men physiologically than "normal" men.
Since the Internet provides unlimited number of websites that feature any sexual desire that the user wants, it results in sexual arousal because the stimuli are new. Carnes think that the Internet can allow people to see any of their fantasy, which usually do not exist in most people's daily lives. These images can be reactivated during the sexual intercourse.
It is normal to correlate the erection of the penis with male sexual arousal. Physical or psychological stimulation, or both, leads to vasodilation and the increased blood flow engorges the three spongy areas that run along the length of the penis (the two corpora cavernosa and the corpus spongiosum). The penis grows enlarged and firm, the skin of the scrotum is pulled tighter, and the testes are pulled up against the body.[5] However, the relationship between erection and arousal is not one-to-one. After their mid-forties, some men report that they do not always have an erection when they are sexually aroused.[6] Equally, a male erection can occur during sleep (nocturnal penile tumescence) without conscious sexual arousal or due to mechanical stimulation (e.g. rubbing against the bed sheet) alone. A young man— or one with a strong libido— may experience enough sexual arousal for an erection to result from a passing thought, or just the sight of a passerby. Once erect, his penis may gain enough stimulation from contact with the inside of his clothing to maintain and encourage it for some time.[7]
Tertiary sexual dysfunction results from psychological and social factors. Reduced libido, desire, or experience of arousal could be due to psychological or situational factors such as depression, anxiety, and changes in relationships. Both sexes experience reduced sexual desire after SCI, and almost half of men and almost three quarters of women have trouble becoming psychologically aroused. Depression is the most common cause of problems with arousal in people with SCI. People frequently experience grief and despair initially after the injury. Anxiety and drug and alcohol abuse may increase after discharge from a hospital as new challenges occur, which can exacerbate sexual difficulties. Drug and alcohol abuse increase unhealthy behaviors, straining relationships and social functioning.
In the DSM-5, male hypoactive sexual desire disorder is characterized by "persistently or recurrently deficient (or absent) sexual/erotic thoughts or fantasies and desire for sexual activity", as judged by a clinician with consideration for the patient's age and cultural context. Female sexual interest/arousal disorder is defined as a "lack of, or significantly reduced, sexual interest/arousal", manifesting as at least three of the following symptoms: no or little interest in sexual activity, no or few sexual thoughts, no or few attempts to initiate sexual activity or respond to partner's initiation, no or little sexual pleasure/excitement in 75–100% of sexual experiences, no or little sexual interest in internal or external erotic stimuli, and no or few genital/nongenital sensations in 75–100% of sexual experiences.