Psychology in Your Life

Transcription

1 Sarah Grison Todd Heatherton Michael Gazzaniga Psychology in Your Life SECOND EDITION Chapter 10 Sex, Gender, and Sexuality 2016 W. W. Norton & Company, Inc. 1

2 10.1 How Does Biology Make Us Male or Female? Gender Does Not Equal Biological Sex Biological sex: the physical aspects of being male or female, as determined by genetics, hormones, and brain/environmental interactions. Gender describes the psychological and social differences between being male or female. Most people feel that their gender matches their biological sex. But approximately 1 percent to 3 percent of the population reports being transgender, meaning they feel their gender is different from their biological sex. 2

3 Gender Does Not Equal Biological Sex In addition, gender can extend beyond the two traditional choices of male and female. Some people don t feel especially male or female. Other people may feel more male in some situations and more female in others. We simply do not know how many people experience gender nonconformity. 3

4 The Sex Chromosomes The 23rd chromosome from each parent determines the zygote s biological sex. The mother s egg cell always contributes an X chromosome as the 23rd chromosome of the zygote. In about half of conceptions, the father s sperm cell also contributes an X chromosome, so the zygote has XX sex chromosomes. This means that the zygote is female (Figure 10.2a). And in about half of conceptions, the father s sperm cell contributes a Y chromosome instead, so the zygote has XY sex chromosomes. In this case, the zygote is male (Figure 10.2b). 4

5 Sex Glands (1) Once the sex chromosomes of a zygote are determined, they further influence biological sex by affecting what sex glands, or gonads, the zygote will eventually develop. Until about the sixth week of development, male and female embryos are the same, except at the genetic level. Around six to seven weeks, embryos with XY sex chromosomes start to develop the male sex glands, called testes; and embryos with XX chromosomes start to develop the female sex glands, called ovaries. The Y chromosome contains a special gene that affects how the gonads develop. This gene is called SRY, which stands for sex determining region on the Y chromosome. Female-ness is the default human biological state: the embryo will develop a female reproductive system unless it is masculinized by hormonal action. 5

6 Sex Glands (2) These sex glands are part of the endocrine system, and they release chemicals called hormones into the bloodstream. During puberty, the ovaries begin to release more of one class of sex hormones, called estrogens. In males, the testes release greater amounts of another class of hormones, called androgens. However, all people have estrogens and androgens, and both are crucial to proper development. As the developing human undergoes puberty, the hormones released by the sex glands cause physical changes to occur that are referred to as secondary sex characteristics. 6

7 Secondary Sex Characteristics (2) Because they are not directly related to sexual reproduction, these characteristics are called secondary. These changes start to appear in girls at about 8 years of age and in boys at about 9 or 10. For both sexes, this includes the development of darker and thicker body hair on the legs, in the armpits, and in the pubic area. In addition, both sexes experience a growth spurt. Females gain more fat, their waists become more defined, and their breasts develop. Males gain more muscle mass and develop facial hair; their voices deepen, and their jaws become more angular. 7

8 Primary Sex Characteristics (1) Because they are directly related to sexual reproduction, these characteristics are called primary. The genitals do not reach full maturity until about two years after the adolescent growth spurt. In females, increases in estrogens cause primary sex characteristics such as the maturation of the uterus, the vagina, and the two ovaries, including the egg cells contained in the ovaries. In males, increases in androgens cause primary sex characteristics that include the maturation of the penis and the two testes and the beginning of sperm cell production in the testes. The clearest sign of primary sex characteristics in a female occurs when she experiences menarche, the first menstrual period. 8

9 Primary Sex Characteristics (2) 9

10 Menarche and Spermarche The clearest sign of primary sex characteristics in a female occurs when she experiences menarche, the first menstrual period. Menarche usually occurs at about 12 and a half years of age, but is beginning earlier than it did 50 years ago. In males, outward signs like muscle development and voice changes are more obvious, but the most important aspect of physical development is not outwardly visible. This important change, the beginning of sperm cell production in the testes, is called spermarche, and usually occurs at about age

11 Is Biological Sex Reflected in Our Brains? There are very small differences between the brains of males and females. However, these differences are not necessarily caused by sex difference: the social environment also shapes how our brain develops, and males and females experience different environments in our society. Across most measures, male and female brains are remarkably similar. According to the gender similarities hypothesis, males and females are similar in most psychological processes. 11

12 Why Are Males More Physically Aggressive Than Females? Some research has linked physical aggression with levels of testosterone, and males typically have more testosterone than females However, research on human subjects does not confirm a clear cause-and-effect relationship between hormone levels and aggressive behaviors. The effect of testosterone on aggression appears to be mediated by social and cultural factors. Higher testosterone levels are associated with more activation of the amygdala, and less activation of the prefrontal cortex when viewing angry faces. 12

13 Are You Male or Female? How Do You Know? Are your sex chromosomes XX or XY? What makes someone male or female? Should athletes have their chromosomes, internal genitals, and hormone levels tested? What rights to bodily privacy should we have? 13

14 Intersexuality When people do not clearly fall into the binary of being biologically male or biologically female, they are experiencing intersexuality. About 1 or 2 of every 100 people experience some ambiguity in their biological sex. One cause of intersexuality is when the merging sperm cell and egg cell do not provide the usual combination of XX or XY sex chromosomes to the new zygote (e.g., Kleinfelter syndrome XXY) 14

15 Section 10.2 Why Do We Act Masculine or Feminine? Gender is different from biological sex. It refers to the social, cultural, and psychological aspects of masculinity and femininity. We learn what is masculine and feminine by observing others and organizing the information we see into mental categories. These categories are called gender schemas. A gender schema is a knowledge structure that contains information about aspects of gender, including social expectations, traits, interests, thoughts, and feelings. 15

16 Gender Stereotypes (1) When we use gender schemas as mental shortcuts for processing information, we are using gender stereotypes. Gender stereotypes reflect commonly held assumptions about the qualities of men and women. However, it is important to note that we can update our schemas with new information so the schemas do not become stuck on rigid stereotypes. 16

17 Gender Roles Gender roles are all the positions, characteristics, and interests considered normal and appropriate for males or for females in a particular culture. Gender role socialization is the idea that we develop culture-specific expectations about gender roles by being exposed to social information in the environment around us. 17

18 Three Forces of Gender Role Socialization Cause Us to Act in a Gender-Conforming Manner 1. Observational Learning: we watch what other people do. 2. Modeling: we imitate people s actions 3. Operant Conditioning: our behavior has either positive or negative consequences, which make us either repeat or avoid the same behavior in the future. 18

19 Gender Role Socialization (1) The positions, characteristics, and interests considered normal and appropriate for males or for females may seem natural, but they are learned. Gender roles differ across time and place. Think of other historical periods and other geographic locations: how are gender roles different from those in our society today? 19

20 Gender Identity The story of David Reimer s life shows how an individual s desire to express an inner gender identity may conflict with their gender role socialization. An individual s gender identity is not exclusively dependent upon genitals, chromosomes, or hormones. 20

21 Cognitive Development of Gender Identity As children develop, they begin to categorize themselves and others in terms of gender. By about age 4, children think of themselves and others in a stable way as boys or girls. Between ages 5 and 7, children recognize that their gender identity does not change even if they dress or act in ways associated with the other gender. 21

22 Gender Expression (1) Gender expression is the way people communicate their gender through clothes, interests, and language. Gender expression is completely unrelated to their gender identity. Even when a person has a clear gender identity, a particular situation can alter the person s gender expression in a variety of ways. 22

23 Variation in Gender Identity (1) Most people identify with the sex they were defined as at birth. Others don t feel or think they are particularly male or female, or their gender identity may change. The term genderqueer is sometimes used to describe this gender identity. Additionally, some people think and feel that they have aspects of being male and aspects of being female. This gender identity is androgynous. 23

24 Variation in Gender Identity (2) 24

25 Transgender (1) Someone whose gender identity does not match the sex they were assigned at birth is considered transgender. Transgender individuals often change their behavior and appearance to fit with the identity they feel with. Some may also use surgeries or hormones to transform their bodies, though others may not. 25

26 Gender Dysphoria Being transgender is not a psychological disorder. However, feelings of discontent with one s assigned gender can become dysfunctional if they are present for 6 months or more and also cause significant distress. The distress, anxiety, and depression that transgender people may face as a result of living in a discriminatory society may result in gender dysphoria, which is recognized by the APA as a psychological disorder. 26

27 Transgender Rights The U.S. Equal Employment Opportunity Commission (EEOC) prohibits inappropriate treatment of people who are transgender and gender nonconforming. In addition, 19 states and Washington, D.C., have adopted employment laws that prohibit discrimination on the basis of gender identity. Communities in California, Philadelphia, Texas, Oregon, and Washington, D.C., have passed legislation requiring gender-neutral bathrooms. 27

28 Section 10.3 How Do We Vary in Sexual Orientation? Sexual orientation is a person s enduring sexual, emotional, and/or romantic attraction to other people. Like biological sex and gender identity, sexual orientation can be viewed as a continuum. Sexual behavior sometimes veers away from orientation norms, so we cannot always easily ascertain a person s orientation (may need more information) 28

29 The Four Main Types of Sexual Orientation 29

30 The Four Main Types of Sexual Orientation 1. Heterosexual: A sexual orientation whereby a person is sexually, emotionally, and/or romantically attracted to people of another sex. 2. Homosexual: A sexual orientation whereby a person is sexually, emotionally, and/or romantically attracted to people of the same sex. Males refer to themselves as gay, females refer to themselves as lesbian (usually). 3. Bisexual: A sexual orientation whereby a person is sexually, emotionally, and/or romantically attracted to people of the same sex and people of another sex. 4. Asexual: A sexual orientation whereby a person does not experience sexual attraction but may experience emotional and/or romantic attraction. 30

31 Queering Sexual Orientation One difficulty in describing sexual orientation is based on the terminology itself. The terms homosexual and heterosexual mean that a person has a specific biological sex or gender and is attracted to people of either the same sex or gender or another sex or gender. But as you have learned, some people experience variations in biological sex or gender. In addition, some people who experience fluidity in sexual orientation may prefer the term queer. 31

32 What Causes a Certain Sexual Orientation? Environment may play a role. Early psychoanalytic theories suggested that parenting influences sexual orientation. However, the overwhelming majority of studies have found little or no evidence that parents affect sexual orientation of their children. Almost no psychologists or physicians believe that sexual orientation is a choice or that it can be changed. If environment does influence sexual orientation, research has not revealed what these environmental factors are. 32

33 What Causes a Certain Sexual Orientation? (2) Biological Factors may play a role Genes, and Brain Structures / Functions Prenatal factors including mother s immune system, and Hormones Why does the cause of a homosexual orientation matter? Why are biological theories of sexual orientation more popular today? Why does it matter if people chose their sexual orientation, or could change it? 33

34 Section 10.4 What Motivates Us to Have Sexual Relations (or Not to)? Desire is a person s psychological experience of wanting to engage in sexual activity. The desire to engage in sexual relations is one of the most durable and powerful motivators that we humans experience. What motivates us to have sex varies considerably among individuals and across circumstances. Our sexual motivation is generally influenced by three factors: biology, our environment and culture, and individual differences. 34

35 The Sexual Response Cycle (1) Masters and Johnson s research proposed a four-stage pattern of physiological and psychological responses during sex. 1. Excitement 2. Plateau 3. Orgasm 4. Resolution Note that males experience a Refractory Period following orgasm 35

36 Hormones and Sexual Behavior (1) Hormones affect sexual behavior by influencing the physical development of the brain and body during puberty. But hormones also help motivate sexual behavior. Some research suggests that testosterone, in particular, can play a role in promoting sexual behavior. Girls with Congenital Adrenal Hyperplasia have a tendency toward being lesbian or bisexual as they become adults 36

37 Hormones and Sexual Behavior (3) While males generally have more testosterone than females, and males are more likely to engage in sexually risky behavior, there are many possible confounding variables. For example, going home with a stranger carries a much different level of risk for men and women in our society. Women are much more likely to experience sexual assault or rape or to be socially sanctioned for engaging in promiscuous behavior. 37

38 Hormones, or Violence and Sexual Double Standards? 38

39 Environmental Context Influences Our Motivation for Sexual Activity (1) Social and cultural norms exert a strong influence on when and how people engage in sexual behavior. For example, the frequency with which we have sex varies by cultures. People in Greece and Croatia report having the most sex, between 134 and 138 times per year, whereas people in Japan have the least amount of sex at 45 times per year. Americans reported that they have sex about twice per week, or 113 times per year. 39

40 Environmental Context Influences Our Motivation for Sexual Activity (2) Even within the United States, there are cultural differences in sexual behavior. For example, adult males view casual sex before marriage as being more acceptable than do adult females. By contrast, young adult males and young adult females tend to have similar views about the acceptability of casual sex before marriage. Beliefs about the acceptability and risk of engaging in particular behaviors thus vary by age and gender. 40

41 Mate Preferences Affect Our Motivation for Sex (1) Culturally constructed ideas about what traits are attractive or desirable shape our willingness to engage in sexual behavior with potential sexual partners. For example, in our culture, men are taught to value physical attractiveness and youth while women are taught to value commitment, emotional stability, and social factors like financial stability. 41

42 Mate Preferences Affect Our Motivation for Sex (2) Evolutionary accounts of human mating are not widely accepted because they fail to account for the complexity of human desire and choice, as well as the influence of culture. For example, humans today often prolong reproducing until later in life, and many choose partners who are not evolutionarily advantageous It also normalizes and focuses on heterosexual relations to the detriment of queer sexualities and gender identities. 42

43 Inner Thoughts and Environmental Stimuli Affect Our Motivation for Sex People have inner fantasies about sex, and those fantasies may be influenced by environmental stimuli like pornographic videos, erotic books, or sexting. Research shows that pornography that focuses on male pleasure and male perspectives is not as popular with women. Viewing porn does not diminish a male s interest in long-term committed relationships, but it may skew views about attractiveness, or reduce people s satisfaction with their sexual partner. 43

44 Individual Differences Influence Our Motivation for Sexual Activity (1) As you have learned, biological and environmental factors motivate people to have sex or not. Inner thoughts also play a role, as people experience sexual fantasies and particular desires. A paraphilia is an unchanging sexual interest, arousal, and/or behavior associated with an object, type of person, and/or situation not usually associated with sex. Paraphilias may increase motivation for specific sexual experiences. 44

45 Individual Differences Influence Our Motivation for Sexual Activity (2) Sexual sadism and sexual masochism, and some of the other paraphilias, are not inherently psychologically unhealthy. They can be practiced in psychologically healthy ways by consenting adults. However, healthy participation requires each person s consent as well as a great deal of communication, emotional maturity, and honesty between the adults engaging in these sexual practices. 45

46 Individual Differences Influence Our Motivation for Sexual Activity (3) The Fifty Shades book trilogy and movie adaptation have received lots of attention for portraying two people, Christian and Ana, engaging in bondage, domination, sadism, and masochism (BDSM). However, some critics have suggested that Fifty Shades does not depict psychologically healthy sexual activities, in part because Ana does not seem truly comfortable with their sexual activities. If Ana is not fully consenting, Fifty Shades may be depicting sexual sadism disorder and sexual masochism disorder. 46

47 Sexual Dysfunction Can Reduce Motivation for Sex (1) A sexual dysfunction is a significant and enduring problem in sexual functioning or pleasure (specifically related to desire, arousal, orgasm, and/or sexual pain). According to a large survey, approximately 43 percent of women and 31 percent of men report experiencing some kind of sexual problem at some point in their lives. These statistics have been criticized by researchers as misrepresenting sexual problems. Some argue that reduced sexual desire can be a completely healthy and functional response for people who are tired, face high levels of stress, or experience psychological or physical threats from their partners. 47

48 Sexual Dysfunction Can Reduce Motivation for Sex (3) Many psychological factors are associated with sexual dysfunction. Changes in finances are associated with increased risk for certain dysfunctions, perhaps due to the stress associated with such changes. Feeling less physical and emotional satisfaction and happiness is associated with all types of sexual dysfunction except premature ejaculation. And a traumatic sexual experience can decrease sexual functioning, even years after the event. Research that focuses solely on the genital-function aspects of sexual dysfunction may fail to identify how thoughts, feelings, and actions may contribute to the issue. 48