HDV 313 - Human Sexuality with professor Becky Burch PDF

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Human Sexuality with professor Becky Burch...

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Aug 27 Ch. 1 Cross Species Universals: As a rule in humans and in others animals, the sex that puts forth more investment in offspring, both in reproduction and in raising the offspring, is the “choosier” sex-the more discriminating sex. The sex that invest less, usually competes for acceptance from this choosier sex. Masturbation: Many mammal species masturbate. The most vivid examples are primateschimpanzees (bonobos). Homosexuality: Can be seen in primates and other mammals, but not lifelong as seen in humans. Most documented cases of homosexuality in primates are part of the dominance hierarchy, with submissive males being receptive to sexual advances by dominant males. A great deal of homosexual behavior is seen in bonobos, both in females and males, and between juveniles and adults. Cross Cultural Universals: ● Incest taboos (#1)

condemnation of rape

● Postpartum sex taboo

exchange of sex for resources Cultural Differences:

Sexual behaviorsForeplay: Kissing. Touching. Pull out hair. Bite off partner’s eyebrows/eyelashes In the south pacific, the woman sticks her fingers in the man’s ear. In other areas, the man puts a fish in the woman’s vulva and licks it out. Aug. 29 Masturbation: in some areas females may be forbidden. In others, females may be able to masturbate in public, but can’t use their hands. Homosexuality: some cultures forbid it, and they report they have no homosexuals. Others encourage male/male relations as rites of passage. Others allow experimentation through childhood/adolescence, then forbid or frown upon homosexuality in adulthood. Standards of beauty: some cultures prize perky young breasts, other prefer sagging, pendulous breasts. Some cultures also prefer elongated labia. Ideal body size and amount of fat varies widely. Keep in mind the overwhelming similarities in behaviors in different species, genders, orientations, cultures, and generations while we examine the differences between them. History of Sexuality Sexuality in the Ancient Mediterranean

Some ancient medical texts discuss cures for STDs. Male circumcision was first performed in egypt. Egyptian women inserted sponges, etc. into their vaginas as forms of contraception. Abortion was forbidden. Egyptians condemned adultery, but it appears to have been relatively common. Prostitution was common, and temple prostitutes often greeted worshippers.

Greece (1000-200 B.C.E.) The greeks were more sexually permissive than the Hebrews, with stories and myths full of incest, rape, and beastiality Greek pederasty was considered a natural form of sexuality, where an older man would mentor a post-pubescent boy. They would engage in sexual activities. Love was discussed in homoerotic terms where man’s nonsexual love for another man was seen as the ideal by Plato, which led to the term platonic for nonsexual friendships. Sexuality in Ancient Asia Early China had many sex manuals with explicit pictures and instructions, aphrodisiacs and sexual devices. Stressed importance of female orgasm. Same-sex relations were not discouraged but viewed as a wasteful use of sperm. The Chinese developed Polygamy was practived until very late in Chinese history- the average middle class male had 3-12 wives and concubines. India Sex in India was viewed as a positive pursuit and a source of power and magic. India’s social system was basically patriarchal. Female infanticide was common. The Kamasutra: fourth century B.C.E.- describes eight kinds of love-biting, eight stages of oral sex, and nine way to move the penis in the vagina. Widows in India were forbidden to remarry, leading many to the ritual act of sati, throwing themselves on their husband’s burning funeral pyre to die. The Enlightenment (1700s) Considered sexual pleasure as natural and desirable. Sexuality became so free there was an unprecedented rise in non-marital pregnancy. Homosexuality was condemned and persecuted. Sex in American History The Colonies: The Puritan Ethic Severe sanctions for sexual transgressions including death for sodomy, bestiality, adultery, and rape, although they did believe that sexuality was good and proper with marriage. Bundling: young couples were allowed to share a bed as long as they were clothed and wrapped in sheets or had a wooden “bundling board” between them. Sept. 3 Ch. 2

Evolutionary Perspective Evolutionary Theory: there will always be certain members of a population that have more offspring than others. If an organism possesses a characteristic that helps it survive and reproduce in an environment, it is likely to live longer and have more offspring. Those genes stay in the gene pool- these are the genes we have inherited. It is important to remember that evolutionary theory can provide an explanation for behavior, but it does not provide a justification. In some cases, it was beneficial to someone’s reproduction and survival of offspring to murder others- more food to go around, less competition, less danger, etc. this does not dictate that murder is morally correct.

Evolutionary theory of sexual behavior Sex differences can be traced to three basic biological differences between the sexes: 1. Genetic assurance: females have greater genetic assurance- they are sure that their children are theirs. 2. Parental investment: procreation requires a much greater biological investment from female than the male-pregnancy, childbird, breast-feeding, and child care. 3. Reproductive potential: a female’s reproductive capacity is limited-about one baby per year over a period of 25-30 years. Males produce hundreds of thousands of sperm daily and remain fertile over a much longer period of time. The reproductive potential of a male, therefore, far exceeds that of a female. Since eggs are scarce, and females must bear the primary burden of childcare, females should be careful when it comes to mate selection and emphasize a male’s ability to provide for, and willingness to commit to them and their child. Moulay Ismail - impregnated over 1000 women Valentina Vassilyeva - 69 babies Males should be more willing to have sex, have more partners, and behave in ways that would increase the number of progeny (offspring). In any species, the sex that invests more in the offspring will be more selective about who it has sex with. Evolutionary theory also predicts that there will be some similarities in male and female mate preferences. Everyone wants a healthy partner. Globally, good skin condition and health is of great importance. Psychoanalytic perspective: Sigmund Freud: saw sex as one of the key forces in human life. Human behavior was

motivated by instinctual drives, and that the unconscious was responsible for many behaviors. He coined the phrase “libido” meaning sex drive or energy. Freud divided the mind into three sections: id, ego, and superego. Id: unconscious, contains libido- primary source for all instinctual motivation. Seeks immediate gratification- how & whenever possible. Ego: negotiates between the id, the superego, and reality. Superego: internalization of the rules of society and personal goals. Determines what actions are permissible. Psychosexual stages: personality development involved stages where pleasure was derived from erogenous zones. Personality disorders were described as fixation at a psychosexual stage and that we all become fixated at some point in our development. 1. Oral stage- very early stage- infancy- erogenous zone: the mouth. First used for sucking then used for biting. Difficulty during this stage would result in fixation and compulsive talking, eating, smoking, etc. 2. Anal stage- begins during second year, during toilet training. People fixated during the anal stage become anal expulsive- destructive and cruel, or anal retentive- stingy. 3. Phallic stage- children discover their genitals and the genitals of their parents. They attach themselves to the parent of the opposite sex. The boy’s attachment to his mother is the Oedipus complex, a girl’s is the Electra complex. The child wishes to replace their same sex parent. Fixation at the phallic stage leads to males constantly demonstrating their manhood- “macho”. Freud also believed that females at this stage developed penis envy. They become jealous of the male penis and compensate by having children later in life. After this comes a penis of inactivity- the latency stage. At puberty, sexual activity becomes the prime motivator and adults remain in this genital stage. Learning Theory Learning- the process in which the tendency to perform a particular behavior is changed by experience Classical conditioning- involves reflexively learning about the conditions that predict events. This involves involuntary responses. A neutral stimulus is paired with an event that triggers an unconditioned response. This neutral stimulus is now able to trigger that response. Operant conditioning- learning involving the consequences of voluntary behavior. Favorable

outcomes increase the frequency of the behavior, unfavorable outcomes decrease the behavior. Sept. 5 Learning theory- can be used to explain several facets of sexuality. Sexual preferences may be learned- pairing different stimuli with orgasm (very reinforcing) create preferences, sexual habits, and even maladaptive sexual obsessions. Social learning theory People have expectancies- that a specific consequence will follow an action. A person may act a certain way because they expect to be rewarded or punished. Observational learning- people learn vicariously- the more complex the behavior, the more times we must observe it and practice it before we can master it. Research Studies The Kinsey report (1948, 1953): nonrandom sampling, non representative sample. A total of 5300 men and 5940 women participated. Only data from caucasians were published. Several groups were over represented- college students, young, and educated people. Under represented: laborers, less educated people, older people, and minorities. Critics felt Kinsey sought out those with unusual sex practices. The National Health and Social Life Survey (1994): planned to be study of 20,000, but finding disappeared- only 3432 people were interviewed. Not all interviews were private. Excluded college students, elderly, prisons, and small groups (such as Native Americans). Masters and Johnson (1966): direct observations of sexual behavior. Ran physiological tests during the sexual response. 694 subjects- definitely not a random sample. Bell, Weinberg, and Hammersmith (1981): only surveyed homosexuals in San Francisco area who frequented bars. Possibly memory problems for childhood events. Humphreys (1970): no informed consent. Deceived participants. Never briefed them. Acted as a “lookout” for police while he secretly observed sexual behavior. He then took down license plate numbers and traced them to the “subject’s” homes, then interviewed them. Difficulties in sex research: ● Funding ● Confidentiality ● Ethics, triggers, debriefing ● Biased samples: both positively and negatively biased ● Social desirability bias Ch. 4 Sex- the biological aspects of being male or female Gender- the psychological (behavioral, social) characteristics of men and women. Prenatal development:

Sexual reproduction: 2 parents each donate a gamete (sperm or egg), each carrying half a genome (23 chromosomes) which combine to create the offspring (zygote). Most cells in humans contain 46 chromosomes arranged in 23 pairs. The 22 pairs are autosomes. The two sex chromosomes are made up of an X or Y chromosome donated by the man’s sperm. If the male contributes an X chromosome, the child will be female (XX), and if it is a Y, the child will be male (XY). Sexual differentiation in the womb Around week 5-6 of gestation primitive gonads form. The Mullerian (female) or the Wolffian (male) reproductive systems develop by the 10th or 11th week. Sept. 10 The Müllerian (female) or the Wolffian (male) reproductive systems develop by the 10th or 11th week. In female embryos, hormones lead to the disappearance of the Wolffian ducts, and the Müllerian duct fuses to form the uterus, the inner third of the vagina, and the Fallopian tubes. In male embryos, the testes begin producing Müllerian inhibiting factor (MIF) and testosterone, which causes the Müllerian ducts to disappear External sex organs Male and female organs are homologous: they form from the same prenatal tissue. In females, hormones cause the genital tubercle to develop into the clitoris, labia minora, vestibule, and labia majora. In males, androgen stimulates the genital tubercle to develop the penis, the urethra, and the scrotum Hormonal Development and Influences The ovaries produce androgens, estrogen, and progesterone. Estrogen: important for breast, uteral, vaginal development, fat distribution, and the menstrual cycle Progesterone regulates the menstrual cycle and prepares the uterus for pregnancy. The testes produce androgens, estrogen and progesterone. Androgens trigger penile, testicle, muscle growth, body hair, and voice changes. Variations in sexual differentiation These will be explained using the gender binary for simplicity, but clearly they negate the binaryHermaphrodite: born with ovarian and testicular tissue. This can happen in XX, XY, or XXY...BUT having both tissues functional is very, very rare.

Intersexed: born exhibiting a mixture of male and female external genitals. Part of the transgendered community. Many undergo surgery to match their genitalia to that of their gender identity if they choose. Intersexed people were called ‘pseudohermaphrodites’ leading to confusion. Genetic bases: Turner’s syndrome: 1/2500 female births. Usually an ovum without any sex chromosome, resulting in XO (X_). Typical external genitalia, but ovaries do not fully develop- do not produce steroid hormones, causing amenorrhea, infertility. Women have short stature, immature breast development, abnormalities of certain internal organs, and sometimes low IQ. Depending on which parent the only X came from, symptoms differ. If the X is from mother: neurodevelopmental disorders of social cognition. Estrogen and progesterone can trigger development of secondary sexual characteristics. Klinefelter’s syndrome: 1/600 male births. Ovum contains extra X chromosome resulting in XXY. Men with XXY are infertile, tall with feminized contours, have small testicles, low testosterone, some gynecomastia. Testosterone therapy can trigger secondary sex characteristics. XYY syndrome: “super males”. 1/1000. Very tall, low IQ, reproductive issues may result in sterility- thought to be more aggressive (not true) Triple-X syndrome: 1/1000 female births. May cause slightly low IQ, psychological issues and fertility problems. Often goes undiagnosed. Hormonal bases Adrenogenital syndrome (AGS) or Congenital Adrenal Hyperplasia (CAH): 1/5000 1/15000 births. Genetic female (XX) is exposed to large amounts of androgens during prenatal development due to low cortisol levels. The internal organs remain female, but external organs may appear masculinized. 5 alpha reductase syndrome: 1/5500. Genital folds fuse to form the scrotum during male development in utero- DHT is critical for genital fusing. Testosterone is converted by DHT by 5 alpha reductase which is abundant in both sexes. Males that lack 5 alpha reductase undergo incomplete differentiation of external genitalia. These males, in some cultures, are raised in females until puberty. At puberty, the drastic increase in testosterone results in an increase in DHT and these males develop male genitalia and treated as males. They are called Guevedoces- “balls at 12” in the Dominican Republic. Females who lack 5 alpha reductase suffer no grave consequences. Androgen-insensitivity syndrome (AIS): 1 in 41000/99000. Genetic male (XY) does not respond to androgens and develops internal testes with female external genitalia. AIS is typically diagnosed in adolescence when girls do not menstruate. Cause: single error in the gene for the androgen receptor. The testes exist and release normal amounts of androgens,

but the body does not respond. The testes still produce Mullerian inhibiting hormone. The MIH does have some effect, so the vagina is short and the uterus is undeveloped. This occurs in other species- chimps, rats, cows. Gender roles and gender traits Gender binary: idea that there are only two genders. Other cultures and species do not adhere to a strict binary. Gender roles: culturally defined behaviors seen as appropriate for males and females. Gender traits: biologically determined gender-specific behaviors. Gender identity: one’s private sense of gender. Gender Schema Theory: Our Cultural Maps Sandra Bem (1981; 1983; 19878): children think according the schemas, which are cognitive mechanisms that organize our world. Gender schemas organize our thinking about gender as determined by culture. The gender schema becomes so ingrained that people do not even realize they are created by stereotypes. Sept. 24 Testes: manufacture sperm and steroid hormones. Contained within the scrotum. Rise and fall away from the body depending on temp and arousal- maintains optimal spermatogenesis Leydig cells: produce testosterone Seminiferous tubules: sperm-producing tubes winding through the testes Epididymis: storage tube for sperm, connected to the seminiferous tubules Vas deferens: long tube lined with cilia that convoys mature sperm from the epididymis to the seminal vesicles Seminal vesicles: two glands lying behind the bladder: secrete fluid that mixes with sperm. Secretion of the seminal vesicles constitutes the main (50%) and the last fraction of the ejaculates. At ejaculation, semen is a liquid and after contacting with the seminal vesicular secretion, it coagulates Spermatozoa: mature sperm with cell nucleus housing 23 chromosomes, including the sex chromosome that determines gender of baby. There are 12 different shapes. (morphologies) Ejaculatory ducts: conjunction of a vas deferens with a seminal vesicle: runs through the prostate gland. This is where fluid from the seminal vesicles mixes with sperm. Prostate gland: gland under the bladder that secretes prostatic fluid. Also contributes fluid to ejaculate- responsible for liquefaction after coagulation Cowper’s glands: (also bulbourethral glands) lie below the prostate. They empty fluid known as preejaculate, which may contain active sperm, into the urethra. Ampullae: upper part of vas deferens, which contracts during ejaculation and forces sperm into the urethra. Spermatogenesis: (sperm production) sperm is produced in the seminiferous tubules. A

spermatogonium develops in the cells lining the outer wall of the seminiferous tubules and moves toward the center while being nourished by Sertoli cells. Spermatogonium develop into spermatocytes and eventually divides into spermatids. The sperm is composed of a head, which contains and enzyme aiding in fertilization of the egg, a midpiece, which generates energy, and a flagellum, or tail, which propels it. Sperm formation in men typically takes about 72 days. Men produce about 300 million sperm per day. Ejaculation Stimulation builds to a threshold leading to the first stage, when the epididymis, seminal vesicles, and prostate empty fluid into the urethral bulb while the bladder is closed off to prevent urine from being expelled. The second stage leads to contradictions, the expulsion of semen, and usually orgasm. Ejaculate (semen): averages about 1-2 teaspoons or 2-5 milliliters in quantity- 50-150 million sperm per milliliter. What else is in semen? Fructose, citric acid, estrogen, testosterone, prolactin, luteinizing hormone, prostaglandins, follicle stimulating hormone, dopamine, serotonin, melatonin, opioids, pregnancy maintaining proteins, human chorionic gonadotropin, immunosuppressants. The Male Maturation Cycle Male Puberty: during a boy’s early life, his testicles do not produce sperm or testosterone. Around ten years of age the hormonal cycle begins in the brain. The hypothalamus begins releasing gonadotropin releasing hormone (GnRH). GnRH stimulates the anterior pituitary gland to send out follicle-stimulating hormone (FSH) and luteinizing hormone (LH). FSH and LH flow through the circulatory system to the testes where LH stimula...