Final Answer:
The phases of the human sexual response, as described by Masters and Johnson, consist of four stages: excitement, plateau, orgasm, and resolution.
Step-by-step explanation:
The first phase, excitement, involves the initial arousal marked by increased blood flow to the genitalia, muscle tension, and heightened heart rate. This is typically accompanied by physical responses like erection in males and lubrication in females.
The plateau phase follows, characterized by sustained arousal, increased vasocongestion, and heightened physiological responses. This phase serves as a bridge between excitement and orgasm, intensifying sexual tension.
The third phase, orgasm, is the peak of sexual response and involves the release of accumulated sexual tension through rhythmic contractions of pelvic muscles. This phase is accompanied by intense pleasure and a sense of release. Finally, the resolution phase marks the return to a pre-arousal state. Physiological responses, such as muscle relaxation and a decline in heart rate, occur.
It's important to note that these phases can vary among individuals, and factors such as age, health, and relationship dynamics can influence the sexual response cycle. Understanding these phases is crucial for fostering healthy sexual relationships and addressing concerns related to sexual function.