A significant field of research has been emerging on the subjective meaning of asexuality. Discussing this new paradigm of human sexuality requires deep philosophical, ethical, historical and cultural debates that underpin the postulates of this dimension. Far from this objective, this paper aims to raise a brief reflection on the challenges that asexuality brings to the study of human sexuality and its relationship with medical (pathologizing) and social (sexual diversity) practices.

By the end of the twentieth century, the lack of libido or sexual desire has been defined by science as an irrefutable condition of a psychological and physiological disorder related to sex. This statement assumes that sexual involvement is a natural and immutable force, prior to social life, and is expressed as an innate instinct that represents a biological and essential need to humans [1].

In the course of time, this line of thinking has shaped the academic, scientific and social imagination, directing health actions and studies related to sexuality, determining standards of normality and abnormality for its exercise. Several theoretical principles have been built from this perspective, such as the case of the Maslow’s Theory of Hierarchy of Basic Human Needs, a current of thought widely used by nursing and other medical fields as criteria for setting priorities related to admission and care for patients in a health facility [2].

Importantly, this theory categorizes human needs in a descending order. According to its concept of relative necessity, a need can only be met from the satisfaction of other needs considered most important, which are located at the base of the hierarchical pyramid [3,4]. Maslow places the sexual act at the base of this pyramid, as a basic, natural and physiological need, disregarding the complexity of the human being, refusing to analyze the individual from a holistic, historical, social and cultural perspective and reducing them solely to the biological dimension [3].

From this line of thought, the lack of desire/sexual interest is characterized as a disorder that necessarily produces negative impacts on individuals’ self-realization and happiness, which implies a process of medicalization of sexuality, aiming to normalize the said 'sexual dysfunction', according to paradigms established by the medical field. In this sense, the contextualization of asexuality is defined as 'Hypoactive Sexual Desire Disorder' defined by the 'Diagnostic and Statistical Manual of Mental Disorders', published by the American Psychiatric Association, as a deficiency or absence of sexual fantasies and desire to engage in sexual activities [5].

Still, asexuality has been associated, for example, with the natural aging process, in which the loss of libido is identified as a result of the drastic hormonal reduction in men and women, requiring the need for its replacement [6]. For this author, other factors contribute to this condition. Health professionals believe that a status of 'asexuality' is also related to psychogenic and mental factors, religion, type of sexual partners, and cultural issues, although there are not standard recommendations for assessing the status of 'asexuality' in this perspective.

It is noteworthy that the use of the term 'asexuality status' has been often associated with sexual dysfunctions that hinder the maintenance of sexual activity, such as erectile dysfunction, which is common in older men and is as a condition that awakens in the individual the need to search for medical treatment, given that sexual desire remains active. In these cases, it is worth (re) considering the use of the term asexuality.

Without ignoring the existence and importance of sexual disorders, there is need for a brief reflection on medical-centered interventions aimed at 'asexualities', bringing into question the extent to which science should intervene in the human condition in the pursuit to achieve or maintain what is known as health, defined as a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity [7]. Here is the crux of the matter involving asexuality. How to treat and medicalize something that cannot be set as pathology? How to interfere in the life of an individual who is in complete physical, mental and social well-being by not expressing any sexual interest directed to someone else? How to establish that a person has 'Hypoactive Sexual Desire' disorders if they definitely do not identify themselves as having this disorder?

Questions like these must be present in medical practice, giving rise to the view of asexuality in its non-pathologizing essence. Corroborating this statement, a research approaching sexual practices of the US population during the 40’s and the 50’s by the American biologist Alfred Kinsey found that 1% of respondents did not show any interest in sexual practice. However, concerned about the 99% who were actually sexually active, Kinsey did not explore in depth this minority of 1%. This was the first evidence in scientific research about a group of individuals who later were to disrupt the foundations of the most important postulate of human sexuality [8,9], now known to express an asexual identity.

Thus, since the twenty-first century, there has been a subtle emergence of a new conception for the lack of sexual desire. This new line of thought points out that, instead of pathology, the lack of interest in sexual intercourse is related, in fact, to a direction of the affective sexual desire, and it receives the name of asexuality [10]. Visions of asexuality can be seen in the figure 1 below.

Figure 1: Traditional and current views of asexuality.
*The term script may be used to describe the behavior of humans, since little of this behavior can be considered spontaneous. Such scripts are cultural and historical. Faced with sexual scripts, the normative cultural contexts give meaning to sex by engendering norms, rules and sexual doctrines (GAGNON, John; SIMON, William. Sexual conduct – the social sources of human sexuality. Chicago: Aldine Publishing Company, 1973).

It is noteworthy to point out some theoretical conflicts for defining and characterizing asexuality in the field of sexual diversity, especially as a category in the list of sexual orientations. Although most works on sexuality define asexuality as sexual orientation, as valid as heterosexuality, homosexuality and bisexuality, some authors, like Oliveira [11], point out that the constructions of the sexual orientation category are based on the assumption of compulsory sexual interest in a target, which is the main aspect that hinders the understanding of asexuality as a sexual orientation. Gazzola and Morrison [12], in an attempt to include asexuality in the sexual orientation category, reshaped the concept of sexual orientation, defining it as "the aspect of one’s personal and social identity that indicates the presence or absence of targets of one’s sexual attractions or behaviors”.

Regardless of whether or not being in the list of sexual orientations, this new concept for the lack of sexual desire arose from the Asexual Visibility and Education Network (AVEN), the largest and most important asexual community in the world, created with the aim to promote discussions about asexuality, stimulate growth and visibility to the asexual community, and serve as an informational resource for people who identify themselves as asexual and for the scientific community, the media and society in general. This portal has its forum composed of 71,973 members in the United States (US) and in dozens of other countries [11,13].

According to AVEN, asexuality is understood as the sexuality of individuals who do not experience sexual attraction. This definition suggests that there is a difference between sexual desire and sexual attraction. According AVEN members, sexual desire or libido refers to a biologically determined natural response triggered from external stimuli. Sexual attraction, in turn, is one’s direction of sexual desire. Regarding asexual individuals, these have their asexual orientation set due to the lack of sexual attraction, not by sexual behavior, since this last issue, asexual are perfectly capable of having sex even without feeling sexual attraction [13].

Although there is no sexual attraction among asexual people, they may manifest libido (sexual desire) and thus, their condition does not characterize a disease, however, this desire is not directed at anyone. This premise justifies the occurrence of masturbation between asexual individuals [13]. Since it is an autoerotic practice, masturbation does not conflict with the definition of asexuality, as some asexual people practice masturbation, but consider it an end in itself and not a practice that necessarily must evolve to a sexual involvement with a partner [13].

Furthermore, AVEN takes a stand in relation to the difference between asexuality and other practices related to sexual abstinence, for example, celibacy, since these practices are based on one’s abstention or conscious and deliberate suppression of sexual attraction. In this case, the individual feels sexual attraction, but for some specific reason, chooses to abstain from sexual activity. In the case of asexuality, there is no sexual attraction to be suppressed [10].

According to AVEN, asexuality is the most heterogeneous class in the hall of sexual orientation, in which the only common feature of all asexual people is that they do not feel sexual attraction directed to others, however, even this feature has several variations [13].

In this perspective, AVEN members divide asexual people into two basic categories, romantic asexual people, who are individuals who feel romantic attraction and therefore feel love interest and wish to maintain a loving relationship with others, and others who have no interest in getting involved romantically with anyone, characterized as aromantic asexual people [13].

In addition, the asexual members of the aforementioned two asexual communities recognize that the definition of asexuality proposed by AVEN does not include the full range of possibilities of the asexual spectrum. There are individuals who identify themselves as asexual, but are able to feel sexual attraction in very specific circumstances, such as the demisexual people and the gray-asexual (gray-a) people. AVEN characterizes demisexual people as individuals likely to feel sexual attraction to certain people, but only when there is already an affective or emotional contact. There is not a consensus from the asexual people and the scientific community regarding the definition of gray-a people, however, a common feature attributed to all of them is that sexual attraction in these individuals can also occur in very specific situations, in very limited and not entirely clear circumstances. Although they are in the intermediate zone between sexual and asexual people, the gray-a and the demisexual people prefer to identify themselves as asexual due to low frequency of their sexual attraction [9]. The figure 2 includes the various possibilities of existence of asexuality and its relationship with the phases of human sexual response, including sexual desire.

Figure 2: Cycle of human sexual response *(desire, arousal, orgasm, and resolution) applied to asexual individuals in their possibilities of existence.
*Masters and Johnson (Human sexual response. Boston: Lippincott Williams & Wilkins; 1966) described the sexual response into four phases: arousal, plateau, orgasm and resolution. Kaplan, in 1977, established a new scheme: desire, arousal, orgasm, and resolution;
**The sign (+) represents the satisfaction of the respective phase of the cycle and the sign (-) represents the non-experience of that phase;
***Although sexual attraction is not set as a phase of the cycle of human sexual response, it was incorporated in this illustration within the phase "desire" as sexual attraction is sexual desire targeted to someone. In this sense, the sign (+) denotes the presence of sexual attraction, the sign (-) its absence and the sign (+/-) the possibility of sexual attraction in specific situations;
****The asexual individual can adopt standard sexual behavior and have sex, though often forcibly, by the absence of sexual desire and attraction. However, due to the physiological mechanisms, they can evolve in a (+) manner in the other phases of human sexual response.

Moreover, asexual people are in the same arena of fight for rights than the Lesbian, Gay, Bisexual, Transvestite, Transgender and Intersex (LGBTTI) movement, which ultimately turns them in targets of the same prejudice and discrimination perpetrated against the group [9]. However, it is worth highlighting the greater invisibility of asexual people, since they are not included in the social movement for legitimization of sexual orientation and are absent in the acronym that characterizes and determines this group.

This brief reflection points to the plurality and heterogeneity of asexuality, which still faces obstacles to its recognition, especially in the medical field. Amid this scenario, there is need for the production of further studies to aid in the elucidation of relevant and intrinsic issues to the complexity of asexual universe, as well as to fulfill the lack of scientific data related to the theme and that can contribute to the deconstruction of an essentialist, biological and reductionist paradigm of sexuality and sexual desire.

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