who called the stages of development psychosexual stages
Psychosexual development In Freudian psychology, psychosexual development is a central element of the psychoanalytic sexual drive theory, that human beings, from birth, possess an instinctual libido (sexual energy) that develops in five stages. Each stage – the oral, the anal, the phallic, the latent, and the genital – is characterized by the erogenous zone that is the source of the libidinal drive. Sigmund Freud proposed that if the child experienced sexual frustration in relation to any psychosexual developmental stage, he or she would experience anxiety that would persist into adulthood as a neurosis, a functional mental disorder.[1][2]
Puberty On average, girls begin puberty around ages 10–11 and end puberty around 15–17; boys begin around ages 11–12 and end around 16–17.[1][2][3][4][5] The major landmark of puberty for females is menarche, the onset of menstruation, which occurs on average between ages 12 and 13;[6][7][8][9] for males, it is the first ejaculation, which occurs on average at age 13.[10] In the 21st century, the average age at which children, especially girls, reach puberty is lower compared to the 19th century, when it was 15 for girls and 16 for boys.[11] This can be due to any number of factors, including improved nutrition resulting in rapid body growth, increased weight and fat deposition,[12] or exposure to endocrine disruptors such as xenoestrogens, which can at times be due to food consumption or other environmental factors.[13][14] Puberty which starts earlier than usual is known as precocious puberty, and puberty which starts later than usual is known as delayed puberty.