1. Chapter 10 Motivation and Emotion

4. The Motivation of Hunger and Eating: Biological Factors
Brain regulation
Lateral and ventromedial hypothalamus
Paraventricular nucleus
Glucose and digestive regulation
Glucostatic theory
Hormonal regulation
Insulin and leptin
In the early 1900’s, Walter Cannon and A.L. Washburn hypothesized that there is an association between stomach contractions and the experience of hunger; Cannon hypothesized a causal relationship, yet people who have their stomachs removed still experience hunger. This realization led to more complicated theories focusing on the brain, blood sugar, and hormones.
Research in the 40’s and 50’s showed that the hypothalamus, particularly two areas called the lateral hypothalamus (LH) and the ventromedial nucleus of the hypothalamus (VMH), are important in hunger. The LH was thought to be the hunger center, while the VMH was thought to be the satiety center. Subsequent research indicated that this was an oversimplified picture, although the LH and VMH are part of the hunger circuit, they are not the key elements.
The paraventricular nucleus of the hypothalamus has recently been implicating as another influential part of the hunger circuit.
Other research has focused on the role of blood glucose and digestive regulation on hunger; when blood sugar goes down, hunger goes up. Glucostatic theory proposed that fluctuations in blood glucose level are monitored in the brain by glucostats – neurons sensitive to glucose in the surrounding fluid. It appears likely that hunger is regulated , in part, through glucostatic mechanisms.
Hormones circulating in the blood also appear to be related to hunger. Insulin, secreted by the pancreas, must be present for cells to use blood glucose. Increases in insulin increase hunger, and the mere sight and smell of food has been shown to increase insulin.
Recently, a new hormone, leptin, has been discovered to be released from fat cells into the bloodstream. Leptin is believed to signal the hypothalamus about fat stores in the body, causing decreases in hunger when fat stores are high.

5. Figure 10.2
The hypothalamus. This small structure at the base of the forebrain plays a role in regulating
a variety of human biological needs, including hunger. The detailed blowup shows that the hypo-thalamus is made up of a variety of discrete areas. Scientists used to believe that the lateral and ventromedial areas were the brain’s start and stop centers for eating. However, more recent research suggests that the paraventricular nucleus is more crucial to the regulation of hunger.

7. The Motivation of Hunger and Eating: Environmental Factors
Learned preferences and habits
Exposure
When, as well as what
Food-related cues
Appearance, odor, effort required
Stress and arousal
Link between heightened arousal and overeating
Clearly, hunger is related to biology; however, it is also regulated by environmental factors like learned preferences. Studies show that people like foods that are familiar to them; dog meat is a delicacy in some parts of the world. Exposure and observational learning appear to play a part in what we like to eat. Learning also appears to influence when and how much people eat.
Food related cues are environmental cues that have been associated with eating, such as appearance or odor of food, effort required to eat a particular food, etc. Research shows that these external cues influence eating behavior to some extent, beyond biological hunger.
Finally, stress and arousal have been shown to be related to increased eating, with some research indicating that women and chronic dieters are more likely to respond to stress with eating.

10. Eating and Weight: The Roots of Obesity
Genetic Predisposition
Body Mass Index and adoption study
The Concept of Set Point
Size not number of fat cells
Dietary restraint
Disinhibition
Obesity is the condition of being overweight. Criteria differ, but one definition assumes that people are overweight if their weight exceeds their ideal body weight by 20%.
Obesity is a significant health problem, elevating mortality risk.
Research suggests that some people can eat more than others without gaining weight and that this may have a genetic basis. Adults raised by foster parents were compared to biological and foster parents in regard to BMI (weight in kilograms divided by height in meters, squared). Adoptees resembled biological parents, not adoptive. Twin studies suggest that genetic factors account for 61% of the variation in body weight among men and 73% among women.
Lose weight on a diet, gain it back. The reverse is also true. Intentionally put on weight, and have a hard time keeping it on. Richard Keesy, 1995, suggests that our bodies have a set point, or natural point of stability in body weight. This appears to be related to fat cell levels, not number but size of fat cells. The hormone leptin allows the brain to monitor how full the fat cells are. Can you change your set point? Evidence is not encouraging…permanent changes in eating and exercise are usually required.
Researchers have also shown that dietary restraint may contribute to obesity. Chronic dieters restrain themselves from eating and go hungry much of the time, but they are constantly thinking about food. When they give in, they become disinhibited and eat to excess…the “I’ve already blown it” problem.

11. Figure 10.5
Dietary intake in modern versus paleolithic times. Eaton, Shostak, and Konner (1988) estimated the makeup of our paleolithic ancestors’ typical diet and compared it to that of the average person in modern society. They maintain that there have been some striking shifts in dietary intake, and that modern humans ignore nutritional requirements that are the product of millions of years of evolution.

12. Figure 10.6
The heritability of weight. Body mass index is a measure of weight that controls for variations in height. Twin studies reveal that identical twins are much more similar in body mass index than fraternal twins, suggesting that genetic factors account for much of the variation among people in the propensity to become overweight. (Data from Stunkard et al., 1990)

13. Sexual Motivation and Behavior: Determining Desire
Hormonal regulation
Estrogens
Androgens
Testosterone
Pheromones
Synchronized menstrual cycles
Aphrodisiacs
Erotic materials
Attraction to a Partner
The Coolidge effect
Evolutionary factors
Hormones exert considerable influence on sexual behavior in many animals, but human sexuality is influenced by much more than hormones. Research suggests that hormones do have at least a small role in human sexual behavior, as testosterone fluctuations are correlated with sexual activity.
A pheromone is a chemical secreted by one animal that affects the behavior of another, usually detected through the sense of smell. Research on pheromones in humans is inconclusive with regard to sexual desire; however, they have been linked to synchronized ovulation among women who live together.
Aphrodisiacs are substances thought to increase sexual desire. Research shows that oysters, vitamin E, etc., have no real impact on sexual desire. Pharmaceutical companies are, however, working on developing aphrodisiacs, and there are promising leads. Viagra is not a sexual stimulant, improving performance, not desire.
Erotic materials have been shown to elevate sexual desire only for a few hours, but they may have an enduring effect on attitudes about sex. Aggressive pornography may make sexual coercion seem less offensive and may contribute to date rape.
Attraction to a partner is a critical determinant of sexual interest. The phenomenon of a new sexual partner reviving sexual interest is termed the Coolidge effect.
Evolutionary factors in human sexual behavior are theorized to hinge on parental investment, with females being more discriminating in choosing partners and less likely to engage in casual sex. This has been used to explain sex differences such as males thinking about sex more frequently, males emphasizing youthfulness and attractiveness in a potential partner, and females emphasizing status and financial prospects in a potential partner.

14. Figure 10.7
Rape victim-offender relationships. Based on a national survery of 3187 college women, Mary Koss and her colleagues (1988) identified a sample of 468 women who indicated that they had beena victim of rape and who provided information on their relationship to the offender. Contrary to the prevailing stereotype, only a small minority (11%) of these women were raped by a stranger. (Data based on Koss et al., 1988)

15. Figure 10.8
Parental investment theory and mating preferences. Parental investment theory suggests that basic differences between males and females in parental investment have great adaptive significance and lead to gender differences in mating propensities and preferences, as outlined here.

16. Figure 10.9
The gender gap in how much people think about sex. This graph summarizes data on how often males and females think about sex, based on a large-scale survey by Laumann, et al., (1994). As evolutionary theorists would predict, based on parental investment theory, males seem to manifest more interest in sexual activity than their female counterparts.

17. Figure 10.10
The gender gap in desire for a variety of sexual partners. Buss and Schmitt (1993) asked college students about how many sexual partners they ideally would like to have for various time intervals ranging up to one’s entire lifetime. As evolutionary theorists would predict, males are interested in having considerably more partners than females.

18. Figure 10.11
Gender and potential mates’ financial prospects. Consistent with evolutionary theory, Buss (1989) found that females place more emphasis on potential partners’ financial prospects than males do. Moreover, he found that this trend transcended culture. The specific results for 6 of the 37 cultures studied by Buss are shown here.

19. Figure 10.12
Gender and potential mates’ physical attractiveness. Consistent with evolutionary theory, Buss (1989) found that all over the world, males place more emphasis on potential partners’ good looks than do females. The specific results for 6 of the 37 cultures studied by Buss are shown here.

20. Figure 10.13
Evolutionary hypotheses about gender differences in relationship jealousy. Evolutionary theory suggests that the issue of paternity uncertainty creates basic differences between males and females in the types of infidelity that will elicit the strongest feelings of jealousy, as outlined here.

21. Figure 10.14
The gender gap in jealousy. Buss et al. (1992) asked subjects to vividly imagine scenarios involving either sexual or emotional infidelity by their partner. Subjects’ distress while imagining these scenarios was assessed by monitoring various indexes of emotional and physiological arousal. As these results show, sexual infidelity generated the most distress in males, whereas emotional infidelity elicited the most arousal in females.

22. The Mystery of Sexual Orientation
Heterosexual – Bisexual – Homosexual
A continuum
Theories explaining homosexuality
Environmental
Biological
Interactionist
Sexual orientation refers to a person’s preference for emotional and sexual relationships with individuals of the same sex (homosexuality), the other sex (heterosexuality), or either sex (bisexuality).
Recent conceptualizations of sexuality hold that homosexuality and heterosexuality are endpoints on a continuum.
Data on the prevalence of homosexuality suggests that 5-8% of the population may have a homosexual orientation.
Many environmental theories explaining homosexuality have been put forth historically. Freud held that a person must identify with the same sexed parent, or homosexuality results. Behaviorists assert that homosexuality is learned through conditioning. Research has failed to support either theory. What has been found is that most men and women with homosexual orientations can trace their leanings back to early childhood, suggesting a biological basis.
Biological research suggests that there is a genetic predisposition to homosexuality, possibly based on the X chromosome. Anatomical differences between gay and straight men in the size of the anterior hypothalamus have also been found. This structure is larger in men than in women, and this study showed that gay men had a 50% smaller AH than straight men.
Some theorists believe that anatomical brain differences such as these may be due to the organizing effects of prenatal hormones on neurological development.
The interactionist view holds that genes and prenatal hormones shape a child’s temperament, which initiates a chain of events that ultimately shapes sexual orientation.

23. Figure 10.15
Homosexuality and heterosexuality as endpoints on a continuum. Sex researchers view heterosexuality and homosexuality as falling on a continuum rather than make an all-or-none distinction. Kinsey and his associates (1948, 1953) created this seven-point scale (from 0 to 6) to describe people’s sexual orientation. They used the term ambisexual to describe those who fall in the middle of the scale, but such people are commonly called bisexual today.

24. Figure 10.17
Genetics and sexual orientation. A concordance rate indicates the percentage of twin pairs or other pairs of relatives who exhibit the same characteristic. If relatives who share more genetic relatedness show higher concordance rates than relatives who share less genetic overlap, this
evidence suggests a genetic predisposition to the characteristic. Recent studies of both gay men and lesbian women have found higher concordance rates among identical twins than fraternal twins, who, in turn, exhibit more concordance than adoptive siblings. These findings are consistent with the hypothesis that genetic factors influence sexual orientation. (Data from Bailey & Pillard, 1991; Bailey et al., 1993)

25. Figure 10.18
An interactionist theory regarding the development of sexual orientation. As the text explains, Daryl Bem (1996, 1998) has recently proposed a radically different theoretical overview of how sexual orientation develops. His model proposes a developmental sequence in which biological predispositions shape youngsters’ temperament, which in turn shapes learning experiences. Critics have argued that Bem’s model underestimates the importance of biology, overestimates the similarity of males’ and females’ experiences, and posits a rather implausible final step. Nonetheless, it is a thought-provoking theory that is worthy of empirical research.

26. The Human Sexual Response
Masters and Johnson – 1966
Stages:
Excitement
Plateau
Orgasm
Resolution
William Masters and Virginia Johnson conducted groundbreaking research in the 1960s using physiological recording devices to monitor the bodily changes of volunteers engaging in sexual activity. They outlined 4 stages in the sexual response cycle.
The excitement phase is the initial arousal, which escalates quickly. Muscle tension, respiration rate, heart rate and blood pressure increase. Vasocongestion – engorgement of blood vessels occurs in the genitals.
The plateau phase occurs when physiological arousal continues to build, but at a slower pace.
The orgasm phase occurs when sexual arousal reaches its peak intensity and is discharged in a series of muscular contractions that pulsate through the pelvic area. The subjective experience of orgasm is very similar for men and women, although women can be multiorgasmic. On the other hand, they are more likely to engage in intercourse without experiencing an orgasm.
The resolution phase is characterized by subsiding physiological arousal. Men experience a refractory period after orgasm, when they are largely unresponsive to further stimulation. This may last from a few minutes to a few hours and increases with age.

27. Affiliation and Achievement Motivation
Affiliation motive = need for social bonds
Devote more time to interpersonal activities
Worry more about acceptance
Achievement motive = need to excel
Work harder and more persistently
Delay gratification
Pursue competitive careers
Situational influences on achievement motives
Thematic Apperception Test (TAT)
Affiliation motivation is the need to associate with others and to maintain social bonds. People who are relatively high in affiliation motivation tend to devote more time to interpersonal activities and to worry more about acceptance than others do.
Achievement motivation involves the need to excel, especially in competition with others.
People who are relatively high in the need for achievement work harder and more persistently, they tend to delay gratification well and to pursue competitive careers.
Both affiliation and achievement motivation are generally measured using the TAT, a projective test which requires a subject to write or tell stories about what is happening in pictures of people in ambiguous scenes.
Situational factors have been shown to influence achievement motivation, causing it to increase when the probability of success and the incentive value of success are high. Additionally, the pursuit of achievement can be influenced by a fear of failure, so that the motive to avoid failure stimulates achievement.

28. Figure 10.22
Determinants of achievement behavior. According to John Atkinson, a person’s pursuit of achievement in a particular situation depends on several factors. Some of these factors, such as need for achievement or fear of failure, are relatively stable motives that are part of the person’s personality. Many other factors, such as the likelihood and value of success or failure, vary from one situation to another, depending on the circumstances.

29. The Elements of Emotional Experience
Cognitive component
Subjective conscious experience
Physiological component
Bodily (autonomic) arousal
Behavioral component
Characteristic overt expressions
The cognitive component of emotion involves subjective feelings that have an evaluative aspect…a cognitive appraisal of an event is an important element in emotional experience.
The physiological arousal associated with emotion occurs through the actions of the autonomic nervous system. The autonomic nervous system is responsible for the highly emotional fight-or-flight response. The involuntary nature of autonomic response is the reason that measures of autonomic activity like the GSR (galvanic skin response) or polygraph can be used to detect whether someone is uncomfortable with what they are telling you (although polygraph measures are not all that accurate).
In the brain, the limbic system is the emotional circuit, with the hub in a structure called the amygdala.
Behaviorally, emotions are expressed through body language and facial expressions. Research indicates considerable cross-cultural similarities in the ability to differentiate facial expressions of emotion.
Cross-cultural similarities have also been found in the cognitive and behavioral components, although display rules, or norms for regulating appropriate expression of emotion vary from culture to culture.

30. Figure 10.23
Emotion and autonomic arousal. The autonomic nervous system (ANS) is composed of the nerves that connect to the heart, blood vessels, smooth muscles, and glands (consult Figure 3.7 for a more detailed view). The ANS is divided into the sympathetic system, which mobilizes bodily resources in response to stress, and the parasympathetic system, which conserves bodily resources. Emotions are frequently accompanied by sympathetic ANS activation, which leads to goose bumps, sweaty palms, and the other physical responses listed on the left side of the diagram.

32. Figure 10.24
Emotion and the polygraph. A lie detector measures the autonomic arousal that most people experience when they tell a lie. After using nonthreatening questions to establish a baseline, a polygraph examiner looks for signs of arousal (such as the sharp change in GSR shown here)
on incriminating questions. Unfortunately, the polygraph is not a very dependable index of whether people are lying.

33. Feel afraid because pulse is racing Cannon-Bard
Theories of Emotion
James-Lange
Feel afraid because pulse is racing
Cannon-Bard
Thalamus sends signals simultaneously to the cortex and the autonomic nervous system
Schacter’s Two-Factor Theory
Look to external cues to decide what to feel
Evolutionary theories
Innate reactions with little cognitive interpretation
The James-Lange theory of emotion holds that you see a snake, your pulse races, and you feel afraid because your pulse is racing.
The Cannon-Bard theory holds that you see a snake, the information is sent to the thalamus, which relays the signals simultaneously to the cortex and to the autonomic nervous system.
Schacter’s Two-Factor Theory holds that you feel autonomic arousal and look around to see why…if there’s a snake you feel fear.
Misattribution of arousal can occur, where people misinterpret their autonomic arousal. Dutton and Aron (1974) conducted a study where they arranged for young men crossing two bridges to meet an attractive female with a questionnaire in hand…one bridge was 10 feet above a stream, while the other was a swaying, 230 foot suspension bridge. The suspension bridge men called the woman for a date significantly more often than the low bridge men, suggesting misattribution of arousal as attraction rather than fear.
Evolutionary theories of emotion assume that emotions are innate reactions that require little cognitive interpretation. Robert Plutchik (1984, 1993) has devised a model of how primary emotions blend together to form secondary emotions (depicted in figure 10.30).

34. Figure 10.28
Theories of emotion. Three influential theories of emotion are contrasted with one another and with the commonsense view. The James-Lange theory was the first to suggest that feelings of arousal cause emotion, rather than vice versa. Schachter built on this idea by adding a second factor—interpretation (appraisal and labeling) of arousal.

35. Figure 10.29
Primary emotions. Evolutionary theories of emotion attempt to identify primary emotions. Three leading theorists—Silvan Tomkins, Carroll Izard, and Robert Plutchik—have compiled different lists of primary emotions, but this chart shows great overlap among the basic emotions identified by these theorists. (Based on Mandler, 1984)

36. Figure 10.30
Emotional intensity in Plutchik’s model. According to Plutchik, diversity in human emotion is a product of variations in emotional intensity, as well as a blending of primary emotions. Each vertical slice in the diagram is a primary emotion that can be subdivided into emotional expressions of varied intensity, ranging from most intense (top) to least intense (bottom).

37. Commonsense notions incorrect
Happiness
Commonsense notions incorrect
Income, age, parenthood, intelligence, and attractiveness largely uncorrelated
Physical health, good social relationships, religious faith, and culture modestly correlated
Love, marriage, work satisfaction, and personality strongly correlated
Subjective rather than objective reality important
Research on happiness indicates that commonsense notions about what makes people happy are largely incorrect.
Income, age, parenthood, intelligence, and attractiveness are largely uncorrelated with happiness.
Physical health, good social relationships, religious faith, and culture are modestly correlated with happiness.
Love, marriage, work satisfaction, and personality are the only factors shown to be strongly predictive of happiness.
Research indicates that subjective rather than objective reality is what is important in deciding happiness.

38. Figure 10.31
Measuring happiness with a nonverbal scale. Researchers have used a variety of methods to estimate the distribution of happiness. For example, in one study in the United States, respondents were asked to examine the seven facial expressions shown and select the one that “comes closest to expressing how you feel about your life as a whole.” As you can see, the vast majority of participants chose happy faces. (Data adapted from Myers, 1992)

39. Figure 10.33
Happiness and marital status. This graph shows that the percentage of adults characterizing themselves as “very happy” as a function of marital status. Among both women and men, happiness shows up more in those who are married as opposed to those who are separated, divorced, or who have never married. These data and many others suggest that marital satisfaction is a key ingredient of happiness. (Adapted from Myers, 1999)

40. Figure 10.34
Possible causal relations among the correlates of happiness. Although we have considerable data on the correlates of happiness, it is difficult to untangle the possible causal relationships. For example, we know that there is a moderate positive correlation between social activity and happiness, but we can’t say for sure whether high social activity causes happiness or whether happiness causes people to be more socially active. Moreover, in light of the research showing that a third variable—extraversion—correlates with both variables, we have to consider the possibility that extraversion causes both greater social activity and greater happiness.