Hunger. Hunger is both physiological and social / psychological.

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1 Hunger Hunger is both physiological and social / psychological.

2 Physiological and Social Physiological: based on primary drives Social: preferences heavily influenced by experience and culture Ex: Grasshoppers in your eggs? Mmmmmm.. Ok in areas of Mexico Not Ok at Denny s in Salisbury Chapulines

3 What is the significance of Ancel Keys study? Describe Ancel Keys study. What did he demonstrate with his experiment?

4 Minnesota Starvation Experiment Ancel Keys WWII Tested 36 conscientious objectors. Given enough food to maintain their weight Food cut in half Men s weight dropped 25% of starting weight Psychological effects Obsessed with food (Hierarchy)

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6 Who were Cannon and Washburn? What occurred in their well-known study? What did it demonstrate about hunger?

7 Physiology of Hunger Cannon and Washburn s studies showed hunger was partially related to the stomach. But those with their stomachs removed still feel hunger.

8 What is the relationship between glucose and hunger? What does glucose do?

9 Body Chemistry Glucose A sugar that your body gets from fats, used for energy. ( Blood glucose or blood sugar ) The hormone insulin converts glucose to fat.

10 Appetite Hormones Orexin secreted by hypothalamus; triggers hunger secreted by fat cells; sends signals to brain diminishing reward of food Leptin PPY Insulin Obestatin Ghrelin secreted by stomach; sends full signals to brain secreted by empty stomach; sends hunger signals to brain secreted by pancreas; controls blood glucose secreted by digestive tract; sends not hungry signals to brain

11 The Brain In the 1960 s it was discovered that hunger comes from.. The Hypothalamus

12 What are the names of the two areas of the hypothalamus that help to control hunger? What is the function of the lateral hypothalamus? What is the function of the ventromedial hypothalamus?

13 The Hypothalamus & Hunger Along the sides of the hypothalamus is the lateral hypothalamus: which brings on hunger. Stimulate the lateral hypothalamus and even a well fed animal will begin to eat. Lesion the lateral hypothalamus and a starving animal will have no interest in food.

14 The Hypothalamus and Hunger Along the lower middle section of the hypothalamus is the ventromedial hypothalamus: which depresses hunger. Stimulate the ventromedial hypothalamus and the animal will stop eating Lesion the ventromedial hypothalamus the animal will continuously want to eat.

15 What is set point?

16 How does the hypothalamus work? Leptin Leptin is a protein produced by bloated fat cells, designed to reduce eating. Hypothalamus senses rises in leptin and should curb eating and increase activity. Those who eat a lot of sugar may become leptin resistant so the messages go unheeded. Two Theories Set Point Hypothalamus acts like a thermostat. We are meant to be in a certain weight range. When we fall below weight our body will increase hunger and decrease energy expenditure (Basic Metabolic Rate). What happens if we go above our set point?

17 Set point Obese Person Higher set point Eat more to feel satisfied If eat less, become very sensitive to external cues

18 Set Point theory Set Point # of fat cells Size of cells Body weight

19 Gaining weight Increase in body weight Increase in # and size of fat cells Raises set point # of fat cells Size of cells Body weight

20 Losing weight Any loss of weight after age of two No decrease in # of fat cells Decrease in size Weight set point doesn t drop Lowest possible weight gets stuck # of fat cells Size of cells Body weight

21 Hunger and Energy Balance Energy homeostasis Long-term matching of food intake to energy expenditure Baseline metabolic rate (BMR) The body s resting rate of energy expenditure Energy balance: calories consumed match calories expended Positive energy balance: calorie intake exceeds expenditure: weight gain Negative energy balance: calorie intake falls short: weight loss

22 Yo-Yo effect 95 % of wt lost is regained within a year Some dieters put on more wt than lost Famine hypothesis Fat cells think there must be a famine while dieting Rebound when person stops diet to help body survive the next famine

23 Set point and genetics IF High metabolic rate THEN Eat without gaining weight IF Low metabolic rate THEN Gain wt easily

24 Hormones and Sexual Motivation Sexual motivation may have evolved to enable creatures to pass on their genes. Sexual desire and response is not as tied to hormone levels in humans as it is in animals. During ovulation, women show a rise in estrogen and also in testosterone. As this happens, sexual desire rises in women and also in the men around them (whose testosterone level rises). Low levels of testosterone can reduce sexual motivation.

25 Sexual Motivation Physiology: The Sexual Response Cycle Female Sexual Responses: Three basic variations ORGASM PLATEAU EXCITEMENT ORGASM PLATEAU EXCITEMENT Typical Male Sexual Response

26 The Effect of External Stimuli All effects of external stimuli on sexual behavior are more common in men than in women. The short-term effect of exposure to images of nudity and sexuality increases sexual arousal and desire. Possible dangers include: the distortion of our ideas of what is appropriate and effective for mutual sexual satisfaction. the habit of finding sexual response through idealized images may lead to decreased sexual response to real-life sexual partners. Imagined Stimuli The brain is involved in sexuality; people with no genital sensation (e.g. spinal cord injuries) can feel sexual desire. The brain also contains dreams, memories, and fantasies that stimulate sexual desire. Fantasies are not just a replacement for sexual activity; they often accompany sex.

27 What motivates sexual behavior?

28 Adolescent Sexuality A Snapshot of Teenage Sexuality in the United States Proportion of teens aged 15 to 17 who have had intercourse Proportion of sexually active female (and male) teens who reported using contraception at last sex 1995 female 1995 male 2006 female 2006 male PERCENT The teenage pregnancy rate per per 1000

29 Origins of Sexual Orientation Theories suggesting that sexual preference is related to parenting behaviors or childhood abuse are not supported by evidence. Differences appear to begin at birth. This could be genetic, or it could be caused by exposure to hormones or antigens in the womb. The fraternal birth order effect: being born after a brother increases the likelihood of being gay. Cause or Effect? The brain and other differences in sexual orientation Heterosexual men have a certain cell cluster in the hypothalamus that, on average, is larger than in gay men and in women. Gay men are more likely than straight men to be poets, fiction writers, artists, and musicians.

30 Sexual Orientation: Current Views differences in brain 1 anatomy Possible causes of same-sex sexual orientation prenatal hormonal 2 influences genetic 3 influences John Tlumacki/The Boston Globe via Getty

31 Genetics and Homosexuality In fruit flies, a difference in one gene determined sexual orientation and behavior. Homosexuality seems to run in families and among identical twins, but still emerges spontaneously, even in one of a pair of twins. Genes related to homosexuality could be passed on by siblings or by people not living exclusively according to their sexual orientation. Homosexuality and Gender Hormones that affect gender may also affect sexual orientation. In mammals, female fetuses exposed to extra testosterone, and male fetuses exposed to low levels of testosterone, often grow up with: bodies, brains, and faces with traits of the opposite sex. the sexual attraction expected of the opposite sex to one s own sex.

32 Achievement Motivation (Motivation at Work) What motivates us to work? (School, job, sports, video games, relationships etc..) The healthy life, said Sigmund Freud, is filled by love and work. 32

33 Attitudes Towards Work People have different attitudes toward work. Some take it as a: 1. Job: Necessary way to make money. 2. Career: Opportunity to advance from one position to another. 3. Calling: Fulfilling a socially useful activity. 33

34 Flow & Rewards Flow is the experience between no work and a lot of work. Flow marks immersion into one s work. People who flow in their work (artists, dancers, composers etc.) are driven less by extrinsic rewards (money, praise, promotion) and more by intrinsic rewards. 34 Commonly referred to as the zone

35 What is Industrial-Organizational (I/O psychology?) Textbook definition: Application of psychological principles and theories to the workplace What I call it: Study of how people get along at work and are able to perform effectively

36 What is I/O psychology? Sub-areas within I/O Industrial or personnel psychology HR stuff: recruitment, job analysis, selection, training, performance appraisal, compensation, employment law Job performance Organizational psychology Micro: motivation, leadership, teams, worker attitudes, safety & well-being, work-family Macro: org theory, culture, org development & change Human factors & ergonomics Modifying equipment & env to fit workers

37 Personnel Psychology Personnel psychologists assist organizations at various stages of selecting and assessing employees. 37 Identifying people s strengths (analytical, disciplined, eager to learn etc.) and matching them to a particular area of work is the first step toward workplace effectiveness. Interviewers are confident in their ability to predict long-term job performance. However, informal interviews are less informative than standardized tests.

38 Appraising performance Helps decide who to train How to reward and pay people How to harness employee strengths Risks in Appraising performance Halo errors overall evaluation colors their evaluation on work-related behaviors Leniency or severity errors Recency errors when raters focus on easily remembered occurrences.

39 Organizational Psychology - Managing Well Every leader dreams of managing in ways that enhance people s satisfaction, engagement, and productivity in his or her organization. 39 Larry Brown offers 4-5 positive comments for every negative comment. Ezra Shaw/ Getty Images

40 Management Theory Management/Teaching styles relate closely to Intrinsic/Extrinsic Motivators. Theory X Assumes that workers are basically lazy, errorprone, and extrinsically motivated by money. Interested in Maslow s lower needs. Must never be trusted and always be watched. To work more, they must be given money.

41 Management Theory Management/Teaching styles relate closely to Intrinsic/Extrinsic Motivators. Theory Y Assumes that, given challenge and freedom, workers are motivated to achieve self-esteem and to demonstrate their competence and creativity. Interested in Maslow s higher needs.

42 Management Styles

43 When Motives Conflict pproach/approach conflict Approach/approach conflict : According to Lewin, the result of simultaneous attraction to two appealing possibilities, neither of which has any negative qualities. Do I want to go to beach or AP Psychology class? Each option is equally enticing.

44 When Motives Conflict Avoidance/avoidance conflict Avoidance/avoidance conflict: According to Lewin, the result of facing a choice between two undesirable possibilities, neither of which has any positive qualities. Should I stay up all night studying for my science or my math final? (Both are equally unappealing)

45 When Motives Conflict Approach/avoidance conflict Approach/avoidance conflict: According to Lewin, the result of being simultaneously attracted to and repelled by the same goal. Should I ask her to go to the dance with me? (She may say yes; she may say no.)

46 When Motives Conflict Double Approach/ avoidance conflict Double-Approach/avoidance conflict: According to Lewin, the result of having to choose between multiple options, each of which has enjoyable and disagreeable aspects. Should I stay home and wait for my girlfriend to call, or should I go out with my friends and maybe miss the call?

47 Stress In psychology, stress is not a situation, but a response. Psychologists talk about stress and stressors a little different than you or I might: Stress: A physical and mental response to a challenging or threatening situation Stressor: A stressful stimulus or situation demanding adaptation

48 Types of Stress Despite the bad name that stress has, it is actually a vital part of our lives, as long as it is controlled. There are two main types of stress: Acute Stress: A temporary pattern of stressor-activated arousal with a distinct onset, and limited duration» Short term stress Chronic Stress: A continuous state of stressful arousal, persisting over time.» Long term stress

49 Traumatic Stressors Certain events go beyond a normal stressor; examples would be the World Tsunami in 2004, 9/11, Columbine, Hurricane Katriana, 9/11, etc. These are called traumatic stressors. To be considered a traumatic stressor, it must be a situation that threatens yours, or others physical safety and promotes a feeling of helplessness. Human created catastrophes are always worse, why?

50 Response to Traumatic Stressors In the face of catastrophic situations, most people pass through five stages: 1) Psychic Numbness: shock, confusion, lack of understanding 2) Automatic Action: little awareness of the experience, poor memory/recall 3) Communal Effort: people work together, but with little planning 4) Letdown: the setting-in of the magnitude and impact of the situation 5) Recovery: Survivors adapt to changes caused by the disaster

51 PTSD Post Traumatic Stress Disorder: Individuals who have undergone severe ordeals-rape, combat, beatings, torture-may experience a delayed pattern of stress symptoms that can appear as long as years after the event. Victims of PTSD often have the following symptoms: Distracted Disorganized Suffer memory difficulties Experience psychic numbing (diminished hedonic capacity) Feelings of alienation

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53 Response to a Normal Stressor The physical response to a normal stressor is fairly universal as well and follows the same sequence: An initiation of arousal A protective behavioral reaction (fight or flight) Internal response of the autonomic nervous system A decrease in the effectiveness of the immune system This is best explained by Hans Selye s GAS!!!!

54 Selye s General Adaptation Syndrome GAS-A pattern of general physical responses that take essentially the same form in responding to any serious chronic stressor. Alarm Reaction the body mobilizes it s resources to cope with a stressor Resistance the body seems to adapt to the presence of the stressor Exhaustion the body depletes it s resources Level of normal resistance Alarm Reaction Successful Resistance Resistance Illness/death Exhaustion