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 stagethe
oral, the
anal, the
phallic, the
latent, and the
genitalis 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.