The four psychological processes of sexual intercourse: excitement phase, plateau phase, orgasm phase, and resolution phase.

[Psychological Process of Sexual Intercourse] Sexual intercourse, also known as sexual intercourse, refers to the union of male and female reproductive organs.

During sexual activity, people experience an extremely subtle, magical, and pleasurable psychological feeling.

Sexual activity is not only a necessary process for procreation and the continuation of the race, but also serves to satisfy sexual desire and temporarily extinguish the fire of sexual desire.

It can promote emotional and psychological compatibility between husband and wife, enabling both to have a pleasant and happy psychological experience, thereby strengthening their existing love.

Human sexual activity takes place in secrecy. Although it involves everyone, the old ethics and moral concepts of thousands of years have tried to avoid and cover up the issue of sex, and even equated sex with being low and vulgar.

Human sexual intercourse typically lasts from a few minutes to a dozen minutes. It is a continuous and unified psychological and behavioral process driven by sexual desire in both sexes, with sexual behavior progressing from weak to strong and then back to weak.

Modern sexologists divide the human sexual response process during intercourse into four stages: excitement, plateau, orgasm, and resolution. However, in actual sexual life, these four stages are difficult to define precisely.

[Psychological Manifestations During the Excitement Phase] The excitement phase is the preparatory stage before intercourse between the male and female reproductive organs.

For sexual intercourse to begin smoothly and end satisfactorily, sexual arousal is essential to keeping the sexual organs in a state of excitement.

Sexual arousal primarily stems from sexual attraction to the opposite sex. This means that when men and women come into contact with the opposite sex or engage in sexual intercourse, they are often attracted by a mysterious aura emanating from the other person, which involuntarily triggers sexual desire.

Generally speaking, men are easily aroused by a woman's beautiful face, full breasts, rounded buttocks, fair thighs, and naked body.

Women's sexual arousal often comes from men's teasing, hugging, kissing, and touching of erogenous zones (such as the breasts).

In addition, human association and symbolic sexual stimulation are also important sources of stimulation. For example, watching audio-visual products, paintings, and pictures related to sex, and listening to provocative language can all stimulate sexual arousal through a person's rich imagination.

The process of sexual arousal can last from two or three minutes to several hours.

The initiation, intensity, and speed of sexual arousal are also related to the central nervous system transmission process of sexual thoughts.

People with strong sexual desires are aroused quickly, while those with weak sexual desires are aroused slowly.

In addition, an individual's health condition, level of fatigue, sexual environment, and emotions are significantly related to the degree and speed of sexual arousal.

Some scholars believe that male sexual desire is related to the accumulation of semen. When semen accumulates to a certain extent, it puts pressure on the inner wall of the seminal vesicle, stimulates the spinal cord center, and transmits the signal to the brain, thereby generating sexual desire psychologically.

During sexual arousal, both men and women experience increased heart rate, muscle tension, and genital congestion.

When the corpora cavernosa of the penis in men become engorged with blood, the penis becomes erect and hard, the scrotum contracts and tightens, and the testicles rise.

In women, the breasts enlarge, the nipples become erect, the clitoris enlarges, the labia majora and minora become congested and edematous, the uterus rises, and vaginal secretions appear to lubricate the vagina, which is conducive to intercourse and sperm survival; the outer 1/3 of the vaginal wall becomes congested, and the vestibular glands secrete mucus to lubricate the vestibule, thus creating favorable conditions for penile insertion.

[Psychological manifestations of the plateau phase] The plateau phase begins after penile penetration of the vagina.

The plateau period is short, lasting about half a minute to three minutes.

During the plateau phase, as the penis thrusts in and out of the vagina and the reproductive organs contract and relax, both partners experience varying degrees of euphoria, intimacy, and dependence.

To enhance this pleasurable stimulation, both partners move their pelvis back and forth to increase contact between their genitals and the vaginal mucosa, while also increasing the intensity of penile stimulation.

Generally speaking, in the initial stages, the penile thrusting and pelvic movements are gentle, rhythmic, and controlled by the person's will.

As the psychological pleasure gradually intensifies, the movements become faster and more vigorous, which further enhances the feelings of euphoria and intimacy, to the point that the conscious mind can hardly control them, causing the body to move involuntarily and automatically.

The physical contact between the two became more intimate, often involving deep kisses.

Muscle tension and mental excitement increase further, and breathing becomes deeper, faster, or even labored.

The flush that occurs when the chests and abdomens of both partners rub against each other is called sexual flush.

The penis swells and thickens, and vaginal discharge continues. The outer third of the vaginal ring of muscles tightly grips the penis, creating a "gripping" effect that increases sexual stimulation for the man.

The uterus begins to contract forcefully in the later stages of the plateau.

At this point, both partners will experience an impending orgasm, both physiologically and psychologically.

[Psychological manifestations during orgasm] The orgasm is the shortest period experienced during intercourse, lasting only a few seconds. During this brief moment, the euphoria of intercourse reaches its peak, and the psychological experience is very complex, subtle, and difficult to describe.

Before the climax, due to the rapid thrusting of the penis inside the vagina, the stimulation of the penis on the vagina and the stimulation of the vagina on the penis interact, giving both partners a premonition that an orgasm is about to occur.

This is followed by male ejaculation, marking the arrival of orgasm.

If the sexual activity of both partners is coordinated, at the peak of sexual pleasure, the woman's physical tension will suddenly stop first, followed by the man's ejaculation. Ejaculation stimulates the highly sensitive areas of the vaginal mucosa and cervix, giving the man a high level of pleasure and also stimulating the woman to reach a peak of pleasure.

A woman's pleasure begins at the clitoris and then radiates throughout the vulva, sometimes even causing a momentary feeling of dizziness.

A moment later, a warm wave flowed from the genitals to the whole body, and finally, the genital muscles spasmed (i.e., twitched), the level of awareness of the surrounding environment decreased significantly, and a large amount of semen was clearly felt being ejaculated from the penis.

During the orgasm phase, as the climax approaches, both men and women experience faster breathing, increased heart rate, elevated blood pressure, expanded sexual flush, and voluntary and involuntary muscle contractions throughout the body.

The woman first experiences contraction of the lower vaginal muscles, followed by rhythmic uterine contractions from the fundus of the uterus to the cervix.

In men, muscle contractions begin at the junction of the ureter and the prostate opening. The muscles of the ureter and urethra contract in a wave-like manner, generating pressure, expelling semen, and causing ejaculation.

[Psychological manifestations during the resolution phase] After the orgasm, the sexual organs and related parts of the body gradually return to the state before sexual arousal. This process is called the resolution phase, which lasts for 10 to 15 minutes.

However, if no orgasm occurs during intercourse, the resolution period can be prolonged, even lasting half a day to a day.

During the resolution phase, the flushing in both men and women gradually fades, and the congested reproductive organs gradually return to normal.

After ejaculation, the erect penis quickly softens and enters the refractory period.

During the refractory period, sexual arousal temporarily disappears, but after 1 to 2 hours or longer, sexual desire can be rekindled, and the desire for intercourse may arise again, depending on age and health conditions.

The engorged labia and vaginal walls of a woman can return to normal within minutes.

When a woman lies on her back, a mixture of exudate and semen accumulates in her vagina, temporarily forming a pool of semen.

If the relationship between the two partners is intimate and their sex life is harmonious, during the resolution phase, because both partners have experienced the pleasure of sex and gained psychological satisfaction, the psychological affinity between them is further enhanced. They will cherish each other, caress, tenderly hug, and hold each other, and this will continue for a longer period during the resolution phase.