MEDICAL BIOLOGY, HUMAN ANATOMY, PHYSIOLOGY AND PATHOLOGY - Ya.I. Fedoniuk 2010

ANATOMY, PHYSIOLOGY, PATHOLOGY

CHAPTER 9. THE REPRODUCTIVE PROCESS

ANATOMY OF THE REPRODUCTIVE ORGANS

SEXUAL MOTIVATIONS AND THEIR REALIZATION

3. PHYSIOLOGY OF THE SEXUAL ACT

The sexual act is a paired physiological process that begins with the insertion of the Penis into the Vagina and concludes with ejaculation and orgasm.

The male sexual act consists of the following components: insertion of the penis into the vagina, a period of friction (Movements of the penis during intercourse), ejaculation, and orgasm. The sexual act is preceded by a preparatory period (a period of mutual caresses).

The sexual act comprises the following successive phases: excitement, peak sexual tension (plateau), orgasm, and resolution.

The excitement phase is triggered by physiological stimulation of erogenous zones and psycho-emotional cues. Sexual tension develops and progressively increases.

The orgasm phase lasts for several seconds and results from the interaction of various structures across different levels of the Central Nervous system (spinal, diencephalic, and cortical). Orgasm represents the peak of passionate pleasurable sensations.

The resolution phase is characterized by a decrease in sexual arousal; however, in women, continued stimulation during this phase can lead to a recurrent orgasm, which is impossible in men due to a refractory period (i.e., unresponsiveness).

The duration of the sexual act ranges from 1.5 to 4 minutes. Intercourse is accompanied by intense autonomic reactions, such as elevated Blood pressure, increased Heart rate, accelerated breathing, pupil dilation, and others.