Phases of Sexual Development
This issue has been researched both in the course of observation of human infant development [29-32,53,65-66,75-76] and in animal studies [4,8-9,49-50, and others]. It was discovered that pubescence does not occur at once in one’s ontogenesis (one’s development in the current incarnation), but on the contrary various parts of the reproductive system finish developing at different moments in time that sometimes are separated by several years.
The first primitive signs of the activity of the reproductive system can be observed in human infants and the young of mammals in the form of erection of cavernous tissue of genitals even in the first days after birth. This type of erection occurs in response to non-specific influence, for example, as a result of fright, during weeping, eating, experiencing pain, laughing, etc.
The second phase is known as the stage of “adolescent intersexuality”. In human ontogenesis, this takes place from the ages of 7-9 to 15-17. At this age, the generation of androgens increases (these are the male sex hormones, which are also present in the woman’s organism). Androgens are universal regulators of sexuality (at the endocrine system level) in both sexes (see ).
The influence of androgens intensifies sexual manifestations, especially in boys. What is typical of this phase is an absence of a distinct sexual orientation towards representatives of the opposite sex of the same biological species, which can be attributed to immaturity of the corresponding brain structures. A sexual arousal at this stage can be easily induced by inadequate stimuli, including inanimate objects, animals, and representatives of the same sex.
These features are typical not only of humans, but also of all animals that have been studied in this respect; they should not be viewed as some kind of pathology. However, transformation of these reactions into conditioned reflexes — due to an adolescent lacking information about normal sexual relations of adult people — may lead to an inversion of his or her sexual orientation for the rest of life.
It should be noted that it is during the first instances of sexual emotional arousal that the formation of very strong conditioned reflex connections may happen sometimes.
Masturbation is one of the typical sexual manifestations of adolescent age. More than 90% of men and approximately 50% of women have had this type of experience in their past [52,59-60]. Masturbation is typical not only of humans, but also of all mammals studied in this respect (see ).
In the past, masturbation was considered as a terrible vice, a sin, the cause of all known diseases. But today this view was rejected as completely unfounded. One can say with certainty that masturbation (except for cases of its excessive use) does not cause any specific disease directly. It is a natural manifestation of sexuality at a certain stage of sexual development. On the contrary, adolescents who get intimidated with the “terrible consequences” of masturbation while being unable to resist an intensive urge to relieve sexual tension may develop mental disorders.
It does not follow from the above said, though, that frequent masturbation at this age does not have negative consequences. Bioenergetic inputs of orgasms attained in this way are unproductive: the energy spent in such a way could have been sublimated and used for intellectual and physical development. But in dealing with adolescent masturbation, one has to use “positive” methods of correction: not intimidation and threatening, but switching young person’s attention to some kind of beneficial activities. Excessive juvenile sexuality can also be weakened by balanced diet, namely by substituting milk products and bird eggs for meat and fish dishes.
Men enter the third phase of their sexual development — the “adult sexuality” stage — when the process of maturing of the brain structures responsible for adequate sexual orientation completes. In women this corresponds to the moment when they become mentally ready to begin their sexual life.
In the case of mammals, the basis of formation of sexual orientation of males towards female representatives of the same species is the congenital reaction of sexual arousal that occurs as a result of a contact with the so-called “key stimuli” . (This reaction occurs rather late in the individual’s ontogenesis). In non-primate mammals, as well as in insects and fish, these “key stimuli” are represented by sex pheromones. These substances are generated by special glands of female genitals, get into urine, and help males find females that are ready for insemination.
In special experiments, I managed to discover that sex pheromones of female dogs are produced by the vaginal glands and not by the urinary tract. Urine only washes them away from the genitals.
Males of non-primate mammals (except for cetaceans, apparently) perceive sex pheromones through their olfactory system (see  in particular).
Sex pheromones are species specific. One may see how they influence the behavior of healthy adult males by watching the reaction of tom-cats when they are given a valerian tincture to smell. Valerian acid is the cat’s sex pheromone .
In primates, including human beings, the “key stimuli” for males are represented by the sight of female genitals (the visual system also plays the leading role in sexual behavior of male birds). In the course of the following relationships between sexes, formation of the sexual orientation typical of mature males takes place — this time on the basis of activating conditioned reflexes (of course, non-biological factors also have certain influence).
Primates and apparently all animals lack the “key stimuli” that would be peculiar to males and would cause an unconditioned reflex-type of sexual arousal in females. Female sexual orientation forms through a mechanism of conditioned reflexes basing on intraspecific social orientation that is formed according to the laws of “initial socialization” [2,4].
The intensity of organism’s reaction to the “key stimuli” is determined by the level of androgens in the organism. When the bioenergetic systems of the organism are exhausted due to tiredness, malnutrition, or disease, the level of androgens and correspondingly the intensity of this reflex decreases.
But, as I discovered in experiments on dogs, this reflex can be restored by means of pharmacological intervention with androgens and stimulators of the androgen generating system. Among these preparations are testosterone propionate, methyltestosterone, eleutherococc, ginseng. The same regularity is observed in male humans.
Variability of the intensity of this reflex depending on the general condition of the male organism is one of the factors that nature uses for selecting for reproduction only healthy individuals who can be expected to produce viable posterity.