Pheromonal influences on sociosexual behavior in postmenopausal women

[Modern studies of the role of the vomeronasal system in the perception of pheromones and their impact on social and sexual behavior]

The vomeronasal system (VNS) provides regulation of a wide range of autonomic and affective functions, behavioral reactions in response to the specific chemical stimuli pheromones secreted by mammals, including humans. The results of experimental studies confirming the existence of VNS and explaining the basic mechanisms of its functioning are presented. The results of studies of healthy volunteers, explaining the effect of pheromones on a number of functions of the human body, are considered.

A missense polymorphism in the putative pheromone receptor gene VN1R1 is associated with sociosexual behavior

Pheromones regulate social and reproductive behavior in most mammalian species. These effects are mediated by the vomeronasal and main olfactory systems. Effects of putative pheromones on human neuroendocrine activity, brain activity and attractiveness ratings suggest that humans may communicate via similar chemosignaling. Here we studied two samples of younger and older individuals, respectively, with respect to one nonsynonymous polymorphism in the gene encoding the human vomeronasal type-1 receptor 1, VN1R1, and one nonsynonymous polymorphism in the gene encoding the olfactory receptor OR7D4. Participants in both samples had self-reported their sociosexual behavior using the sociosexual orientation inventory, including questions regarding lifetime number of one-night stands, number of partners last year and expected number of partners the coming 5 years. In women, there was a significant association between the VN1R1 polymorphism and sociosexual behavior in both samples, driven specifically by the question regarding one-night stands. Our results support the hypothesis that human social interaction is modulated by communication via chemosignaling.

Beyond Emotion: Love as an Encounter of Myth and Drive

Starting with a review of research on love as an emotion, with an emphasis on romantic love, it is argued that despite strong emotional correlates evidence is lacking to conclude that love would meet the criteria of basic emotions. Theoretical developments are proposed where love is conceived of as a combination of an objectless drive, a desire for love, and a mythical and scripted representation that offers the possibility of labeling the current core affect. I argue that the basic motive for love is not so much the partner’s personal attributes, but rather the benefits of the transformative power of being in love.

Human Body Scents: Do they Influence our Behavior?

Pheromonal communication in the animal world has been of great research interest for a long time. While extraordinary discoveries in this field have been made, the importance of the human sense of smell was of far lower interest. Humans are seen as poor smellers and therefore research about human olfaction remains quite sparse compared with other animals. Nevertheless amazing achievements have been made during the past 15 years. This is a collection of available data on this topic and a controversial discussion on the role of putative human pheromones in our modern way of living. While the focus was definitely put on behavioral changes evoked by putative human pheromones this article also includes other important aspects such as the possible existence of a human vomeronasal organ. If pheromones do have an influence on human behavior there has to be a receptor organ. How are human body scents secreted and turned into odorous substances? And how can con-specifics detect those very odors and transmit them to the brain? Apart from that the most likely candidates for human pheromones are taken on account and their impact on human behavior is shown in various detail.

Female perception of male body odor

Olfaction is one of the most crucial forms of communication among nonhuman animals. Historically, olfaction has been perceived as being of limited importance for humans, but recent research has documented that not only do humans have sensitive olfactory abilities, but also odors have the potential to influence our physiology and behavior. This chapter reviews research on olfactory communication among humans, focusing on the effects of male bodily odors on female physiology and behavior. The process of body odor production and the detection of olfactory signals are reviewed, focusing on potential sex differences in these abilities. The effects of male body odors on female physiological and behavioral effects of body odors are considered. Finally, with specific regard to female mate choice, evidence regarding the influence of the major histocompatibility complex and fluctuating asymmetry on male olfactory cues is reviewed.

Apocrine sweat gland obstruction by antiperspirants allowing transdermal absorption of cutaneous generated hormones and pheromones as a link to the observed incidence rates of breast and prostate cancer in the 20th century

Breast and prostate cancer share similarities and likely represent homologous cancers in females and males, respectively. The role of hormones such as testosterone and estrogen in carcinogenesis is well established. Despite worldwide research efforts, the pathogenesis of these diseases is largely not well understood. Personal care products containing estrogens or xenoestrogens have raised concern as a breast cancer risk, especially in young African-American women. In the United States (US) there is a parallel rise in the incidence in breast and prostate cancer compared to selected non-hormone dependent tumors. Observed US and global breast and prostate cancer incidence increases were occurring before exogenous hormone replacement and xenoestrogen exposure were commonplace. An unintentional, inadvertent, and long term hormone exposure may occur from transdermal absorption of sex hormones and pheromones (androgens) from axillary apocrine sweat gland obstruction by aluminum-based antiperspirants. The global rise in antiperspirant use parallels rises in breast and prostate cancer incidence and mortality rates. A multi-disciplinary literature based set of evidence is presented on how such a link is possible, to prompt confirmatory investigations in the pursuit of unmet needs in breast and prostate cancer etiology and prevention.

A dual physiological character for sexual function: libido and sexual pheromones

Human sexual response is a complex function involving many cerebral, spinal and peripheral aspects; the last are relatively known and benefit from good pharmacological control, as in the case of erectile dysfunction. Spinal cord sexual reflexes also have a good theoretical and experimental description. There is minimal understanding of the cerebral sexual processes (libido, sexual arousal, orgasm). The initial perspective was that the cerebral areas implied in sexuality exert descending stimulatory and inhibitory influences on spinal cord sexual centres/reflexes. This was a wrong supposition, which inhibited progress in this subject, with a considerable impact on a subject's individual and social life. A new approach to sexual function arises from the idea that simple neurological structures can support only simple functions, while a more complex function requires correspondingly complex anatomical structures. For this reason the spinal cord would not be able to realise the integration of multiple (spinal and psychosensorial) stimuli into a unique and coherent ejaculation response. Consequently, all mechanisms implied in human sexuality would be cerebral processes, ejaculation reflexes ascending in evolution to the cerebral level. This new evolutionary concept was developed after 2001 in five distinct articles on the cerebral duality of sexual arousal, sexual hormones, ejaculation and serotonergic receptors. During this period other published results suggested a possible cerebral duality for sexual pheromones and libido in humans. All these dual physiological aspects are integrated in this review into one neurophysiological model, thus trying to further develop the new concepts of sexual function and perhaps relational behaviour. In conclusion, ejaculation is a dual cerebral process with arousal sensation (hormonally modulated) and libido perception (pheromonally modulated) as the afferent part. Two neurophysiological axes could exist in both men and women. In this assumption the mechanisms for libido and sexual arousal are not the only ones invoked, their correlations and implications are also suggested, perhaps critical aspects for further developments in the field.

Central hormonal regulation and dimorphism of arousal

From studies in animals, we have learned that differences in sexual behaviour between males and females reflect anatomical and biochemical differences between the male and female brain. A masculine behaviour (and therefore a masculine brain) results from the biological effect on the developing brain exerted by testosterone, which is secreted by the gonads and aromatized into oestrogens in the brain. However, congenital disorders of the androgen as well as oestrogen signalling in human males have failed to show any appreciable derangement in sexual behaviour. Based on other evidence in animals, sexual differences in brain (and behaviour) are not hormonally triggered but genetically determined. This other theory states that sexual behaviour is determined by the chromosomal sex existing in cells, including brain cells. A number of excitatory and inhibitory signals modulate the activity of certain brain structures. Scientists have begun to test some of these chemicals or their synthetic analogues/antagonists in humans.