What Drives Us: Hunger, Sex, Friendship, and Achievement

Transcription

1 CHAPTER 11 What Drives Us: Hunger, Sex, Friendship, and Achievement Preview Motivation is a need or desire that energizes and directs behavior. Under the influence of Darwin s evolutionary theory, the popular view was that instincts control behavior. Drive-reduction theory maintains that physiological needs create psychological drives that seek to restore internal stability, or homeostasis. In addition, some motivated behaviors increase arousal, and we are pulled by external incentives. According to Maslow, some motives are more compelling than others. Hunger seems to originate from changes in glucose and insulin levels that are monitored by areas deep within the hypothalamus, as well as changes in the levels of appetite hormones such as ghrelin. To control weight, the body also adjusts its basal metabolic rate. Body chemistry and environmental factors together influence our taste preferences. In studying obesity, psychologists have found that a number of physiological factors make it difficult to lose weight permanently. Those who wish to diet should set realistic goals, minimize exposure to food cues, exercise, and make a lifelong change in eating patterns. Like hunger, sexual motivation depends on the interplay of internal and external stimuli. In nonhuman animals, hormones help stimulate sexual activity. In humans, they influence sexual behavior more loosely. One s sexual orientation seems neither willfully chosen nor willfully changed; research links sexual orientation to biological factors. The need to belong is a major influence in motivating human behavior. Social bonds boosted our ancestors survival rates. We experience our need to belong when feeling the gloom of loneliness or joy of love, and when seeking social acceptance. People who excel are often selfdisciplined individuals with strong achievement motivation. Introductory Exercise: Fact or Falsehood? The correct answers to Handout 11 1 are as follows: 1. F 2. F 3. T 4. T 5. T 6. F 7. T 8. F 9. F 10. T 99

2 100 Chapter 11 What Drives Us: Hunger, Sex, Affiliation, and Achievement HANDOUT 11 1 Fact or Falsehood? 1. In wealthy nations, financial satisfaction more strongly predicts feelings of well-being. 2. Humans who have had ulcerated or cancerous stomachs removed do not experience hunger. 3. Part of knowing when to eat is our memory of our last meal. 4. It is possible for two people of the same height, age, and activity level to maintain the same weight, even if one of them eats much more than the other does. 5. Starving all day and eating one big meal at night slows metabolism. 6. Normal fluctuations in sex hormones have a significant effect on human sexual desire. 7. Descriptions of the feelings accompanying orgasm written by men cannot be distinguished from those written by women. 8. Research has shown that homosexuality is linked with problems in a child s relationships with parents. 9. When asked What is it that makes your life meaningful? most people mention meaningful work before anything else. 10. Self-discipline has surpassed intelligence test scores to better predict school performance, attendance, and graduation honors.

3 Chapter 11 What Drives Us: Hunger, Sex, Friendship, and Achievement 101 Guide Objectives Every question in the Test Banks is keyed to one of these objectives. Basic Motivational Concepts Define motivation as psychologists use the term today, and identify the perspectives from which they view motivated behavior. Hunger Describe the physiological factors that produce hunger Discuss cultural and situational factors that influence hunger Discuss the factors that predispose some people to become and remain obese. Sexual Motivation Describe how hormones influence human sexual motivation Describe the human sexual response cycle, and explain how sexual dysfunctions and paraphilias differ Explain how sexually transmitted infections can be prevented Describe how external and imagined stimuli contribute to sexual arousal Discuss the factors that influence teenagers sexual behaviors and use of contraceptives Summarize what research has taught us about sexual orientation Discuss whether scientific research on sexual motivation is value free. Affiliation and Achievement Describe the evidence that points to our human affiliation need our need to belong Describe how social networking influences us Define achievement motivation. Basic Motivational Concepts u Lectures: Why Do Students Go to College or University?; Evolutionary Psychology; Instincts u Feature Film: A Man for All Seasons u Exercises: Exploration Index; Sensation-Seeking Define motivation as psychologists use the term today, and identify the perspectives from which they view motivated behavior. A motivation is a need or desire that energizes behavior and directs it toward a goal. The perspectives useful for studying motivated behavior include (1) instinct/evolutionary perspective, (2) drive-reduction theory, (3) arousal theory, and (4) Abraham Maslow s hierarchy of needs. Under Darwin s influence, early theorists viewed behavior as being controlled by instincts, complex behaviors that are rigidly patterned throughout a species and are unlearned. When it became clear that people were naming, not explaining, various behaviors by calling them instincts, this approach fell into disfavor. The idea that genes predispose species-typical behavior is still influential in evolutionary psychology. u Exercise: How Do You (Should You) Reduce Your Drives? Drive-reduction theory proposes that most physiological needs create aroused psychological states that drive us to reduce or satisfy those needs. The aim of drive reduction is internal stability, or homeostasis. Furthermore, we are not only pushed by internal drives but we are also pulled by external incentives. When there is both a need (hunger) and an incentive (smell of freshly baked bread), we feel strongly driven.

4 102 Chapter 11 What Drives Us: Hunger, Sex, Friendship, and Achievement Arousal theory states that rather than reducing a physiological need or minimizing tension, some motivated behaviors increase arousal. Curiosity-driven behaviors, for example, suggest that too little or too much stimulation can motivate people to seek an optimum level of arousal. Two earlytwentieth-century psychologists studied the relationship of arousal to performance and identified the Yerkes-Dodson law, suggesting that moderate arousal would lead to optimal performance. u Lecture: Maslow s Hierarchy u Exercises: Self-Transcendence Inventory; Meaning in Life Abraham Maslow s hierarchy of needs expresses the idea that, until satisfied, some motives are more compelling than others. At the base of the hierarchy are our physiological needs, such as for food and water. Only if these are met are we prompted to meet our need for safety, and then to meet the uniquely human needs to give and receive love, to belong and be accepted, and to enjoy self-esteem. Beyond this lies the need to actualize one s full potential. Near the end of his life, Maslow suggested that some people reach a level of self-transcendence in which they strive for meaning and purpose that is beyond the self, that is, transpersonal. Hunger The Physiology of Hunger u Feature Film: Alive u Exercise: Factors Influencing Human Eating Behaviors u PsychSim 6: Hunger and the Fat Rat u LaunchPad: Hunger and Eating Describe the physiological factors that produce hunger. Although the stomach s pangs contribute to hunger, variations in body chemistry are more important. Increases in the hormone insulin diminish blood glucose, partly by converting it to stored fat. We do not consciously feel this change in blood chemistry. Rather, our body s internal state is monitored by areas deep within the hypothalamus (for example, the arcuate nucleus), which regulates the body s weight as it influences our feelings of hunger and fullness. One task of the hypothalamus is to monitor levels of the appetite hormones such as ghrelin (which is secreted by an empty stomach). Other appetite hormones include leptin, PYY, and orexin. Some researchers have abandoned the idea that the body has a precise set point a biologically fixed tendency to maintain an optimum weight preferring the term settling point to indicate an environmentally and biologically influenced level at which weight settles in response to caloric input and expenditure. Human bodies regulate weight through the control of food intake, energy output, and basal metabolic rate the body s resting rate of energy expenditure. The Psychology of Hunger u Lecture: Environmental Factors in Eating Discuss cultural and situational factors that influence hunger. Part of knowing when to eat is our memory of our last meal. As time passes, we anticipate eating again and feel hungry. Although some taste preferences are genetic (for example, sweet and salty tastes), conditioning and culture also affect taste. For example, Bedouins enjoy eating the eye of a camel, which most North Americans would find repulsive. Most North Americans also shun dog, rat, and horse meat, all of which are prized elsewhere. A taste may be conditioned, as when people given highly salted foods develop a liking for excess salt or when people who have been sickened by a food develop an aversion to it. We also tend to avoid unfamiliar foods (neophobia), which was adaptive for our ancestors.

5 We eat more when eating with others (through social facilitation). In addition, the size of food portions (called unit basis) and even of bowls, plates, and eating utensils affects how much we eat. Food variety also stimulates eating. Obesity and Weight Control Chapter 11 What Drives Us: Hunger, Sex, Friendship, and Achievement 103 u Lectures: Sleep and Weight Control; Genes, Exercise, and Weight Control; The National Weight Control Registry; Eating to Cope With a Losing Sports Team u Exercises: Healthy/Unhealthy Eating by College Students: Food Photos Experimental Design u LaunchPad: Eating and Weight Gain: A Role for Fidgeting; Eating and Weight Gain: Genetic Engineering u Feature Film: Supersize Me Discuss the factors that predispose some people to become and remain obese. Obesity can be socially toxic, by affecting both how you are treated and how you feel about yourself. Obesity has been associated with lower psychological well-being, especially among women, and increased depression. Obese 6- to 9-year-olds are 60 percent more likely to suffer bullying. And obesity has physical health risks. Yet few overweight people win the battle of the bulge. Fat is an ideal form of stored energy. It is a high-calorie fuel reserve that can carry the body through periods when food is scarce. In fact, in most developing societies today, obesity signals affluence and social status. However, the tendency to eat energy-rich fat or sugar becomes dysfunctional in a world of easily accessible food. Combined with a lack of exercise, the abundance of high-calorie food has led to higher rates of obesity, which raises the risk of illness and shortens life expectancy. According to the World Health Organization, an overweight person has a body mass index (BMI) of 25 or more; someone obese has a BMI of 30 or more. Although genes influence body weight, they do not determine it. People differ in their resting metabolic rates, and once someone gains fat tissue, less energy is needed to maintain that tissue than is needed to maintain other tissue. Unquestionably, environmental factors such as sleep loss, social influence, often eating high-calorie foods, and living a sedentary lifestyle also matter. Those who wish to diet should begin only if they feel motivated and self-disciplined. They should minimize exposure to food cues, boost energy expenditure through exercise, eat healthy foods spaced throughout the day, beware of the binge, make a lifelong change in eating patterns, and connect with a support group. Sexual Motivation u Lectures: Why Do People Have Sex?; Introducing Sexual Motivation; Why Do We Kiss? Sex is a part of life. For all but the tiny fraction of us considered asexual, dating and mating become a high priority from puberty on. The Physiology of Sex Describe how hormones influence human sexual motivation. The sex hormones direct the physical development of male and female sex characteristics and, especially in nonhuman animals, activate sexual behavior. Although testosterone is present in both sexes, males have a higher level of this hormone. The female hormones, the estrogens (such as estradiol) peak during ovulation. In humans, the hormones influence sexual behaviors more loosely, especially once sufficient hormone levels are present. In later life, as sex hormones decline, the frequency of sexual fantasies and intercourse also declines.

6 104 Chapter 11 What Drives Us: Hunger, Sex, Friendship, and Achievement u Lecture: Causes of Sexual Dysfunctions u Video: Mary Roach: 10 Things You Didn t Know About Orgasm Describe the human sexual response cycle, and explain how sexual dysfunctions and paraphilias differ. The human sexual response cycle normally follows a pattern of excitement, plateau, orgasm (which seems to involve similar feelings and brain activity in males and females), and resolution, followed in males by a refractory period, during which renewed arousal and orgasm are not possible. Sexual dysfunctions are problems that consistently impair sexual arousal or functioning. Premature ejaculation and female orgasmic disorder can often be treated by therapy. Erectile disorder is routinely treated by taking a pill. Paraphilias involve sexual arousal from fantasies, behaviors, or urges involving nonhuman objects, the suffering of self or others, and/or nonconsenting persons Explain how sexually transmitted infections can be prevented. Unprotected sex has also led to increased rates of sexually transmitted infections (STIs). Teenage girls, because of their less mature biological development and lower levels of protective antibodies, seem especially vulnerable to STIs. Attempts to protect teens through comprehensive sexeducation programs include a greater emphasis on teen abstinence. Condoms offer only limited protection against certain skin-to-skin STIs, such as herpes, but they do reduce other risks, such as for HIV (human immunodeficiency virus the virus that causes AIDS). The Psychology of Sex u Exercise: Hendrick Sexual Attitudes Scale u Exercise/Video: Hooking Up and Orgasm u Lecture: Gender Differences in Sexual Behavior Describe how external and imagined stimuli contribute to sexual arousal. External stimuli, such as sexually explicit materials, can trigger arousal in both men and women, although the activated brain areas differ somewhat. Sexually coercive material tends to increase viewers acceptance of rape and violence toward women. Images of sexually attractive men and women may lead people to devalue their own partners and relationships. Our imaginations also influence sexual motivation. Wide-awake people become sexually aroused both by memories of prior sexual activities and by fantasies. About 95 percent of both men and women say they have had sexual fantasies. Fantasizing about sex does not indicate a sexual problem or dissatisfaction. If anything, sexually active people have more sexual fantasies. u Lecture: Virginity Pledges Discuss the factors that influence teenagers sexual behaviors and use of contraceptives. Although physical maturation fosters a sexual dimension to adolescents emerging identity, sexual expression varies greatly with time and culture. Compared with European teens, American teens have a a higher pregnancy rate. One reason for this high rate is minimum communication about birth control, as many teenagers are uncomfortable discussing contraception with either parents or partners. Guilt related to sexual activity sometimes results in lack of planned birth control. When passion overwhelms intentions, the result may be conception. Sexually active teens also tend to use alcohol, which can break down normal restraints. Finally, television and movies foster sexual norms of unprotected promiscuity. Teens with high rather than average intelligence more often delay sex. Religious engagement, father presence, and participation in service learning programs are also predictors of sexual restraint.

7 Chapter 11 What Drives Us: Hunger, Sex, Friendship, and Achievement 105 Sexual Orientation u Lecture: Age Differences in Sexual Orientation u Exercises: Attitudes Toward Homosexual Persons u LaunchPad: Homosexuality and the Nature-Nurture Debate Summarize what research has taught us about sexual orientation. Sexual orientation is our enduring sexual attraction toward members of either our own sex (homosexual), the other sex (heterosexual), or both sexes (bisexual). Studies in both Europe and the United States suggest that about 3 or 4 percent of men and 2 percent of women are homosexual. Such studies also tell us that sexual orientation is enduring. Women s sexual orientation tends to be less strongly felt and potentially more fluid and changing than men s, referred to as erotic plasticity. Women are somewhat more likely than men to feel and act on bisexual attractions. There is no evidence that environmental influences determine sexual orientation. No links have been found between homosexuality and a child s relationships with parents, fear or hatred of people of the other gender, levels of sex hormones currently in the blood, or childhood sexual experience. On the other hand, biological influences are evident in studies of same-sex relations in several hundred species, straight-gay differences in body and brain characteristics, genetic studies of family members and twins, and the effect of exposure to certain hormones during critical periods of prenatal development. Sex and Human Values Discuss whether scientific research on sexual motivation is value free. Although research on sexual motivation does not attempt to define the personal meaning of sex in our lives, sex research and education are not value-free. Researchers values should be stated openly, enabling us to debate them and to reflect on our own values. Sex at its human best is lifeuniting and love-renewing. Affiliation and Achievement The Need to Belong u Lectures: The Need for Affiliation; Does Social Rejection Literally Feel Cold? u Exercise: Demonstrating Ostracism: The Train Ride u Feature Film: Cast Away and the Need to Belong Describe the evidence that points to our human affiliation need our need to belong. Social bonds boosted our ancestors survival rate. Adults who formed attachments were more likely to come together to reproduce and to stay together to nurture their offspring to maturity. Cooperation in groups also enhanced survival. People who feel supported by close relationships live with better health and at lower risk for psychological disorder and premature death. When relationships form, we often feel joy. Most people mention before anything else close relationships as making life meaningful. Even our self-esteem is a gauge of how valued and accepted we feel. Attachments can keep people in abusive relationships as the fear of being alone may seem worse than the pain of emotional or physical abuse. When something threatens our social ties, negative emotions overwhelm us. When ostracized, people may engage in self-defeating or antisocial behaviors and underperform on aptitude tests. Ostracism elicits increased activity in the brain s anterior cingulate cortex, which is also activated by physical pain.

8 106 Chapter 11 What Drives Us: Hunger, Sex, Friendship, and Achievement Describe how social networking influences us. Evidence of the human need to belong is the social networking that dominates most of our lives today. But the technology is changing; phone talking now accounts for less than half of U.S. mobile network traffic. In Canada and elsewhere, ing is being displaced by texting, social media sites, and other messaging technology. Among 2010 s entering American collegians, 94 percent were using Facebook or Twitter. Social networkers are less likely to know their real-world neighbors. However, the Internet is diversifying our social networks and is mostly strengthening our connections with people we already know. Social networking also stimulates healthy self-disclosure. We often are less focused on others reactions, less self-conscious, and thus less inhibited. And we are more likely to reveal our real personality. On the negative side, those who score high on narcissism are especially active on social networking sites. Achievement Motivation u Exercises: The Need for Achievement; Achievement and Intrinsic Motivation Define achievement motivation. Achievement motivation is the desire for significant accomplishment, for mastering skills or ideas, for control, and for rapidly attaining a high standard. Those who achieve the most are distinguished not so much by natural ability as by hard work and daily discipline. Self-discipline has been a better predictor of school performance, attendance, and graduation honors than intelligence scores have been. What distinguishes successful people from their equally talented peers is grit.