1. Mod. 38 – Hunger Motivation (p.396-405)

2. Motivation of HUNGER

3. Biological Basis of Hunger
Hunger does NOT come from our stomach.
The Hypothalamus

4. Ventromedial Hypothalamus
Lateral Hypothalamus
Ventromedial Hypothalamus
When stimulated it makes you hungry.
When lesioned (destroyed) you will never be hungry again.
When stimulated you feel full.
When lesioned you will never feel full again.

5. Set Point Theory
hypothalamus acts like a thermostat- to maintain a stable weight (set point weight)
When we drop below that set point weight (when your dieting), the hypothalamus, says for you to eat more, lowers your metabolic rate
Activate the lateral hypothalamus when you diet
Activate the ventromedial hypothalamus when you start to gain weight.
Metabolic rate- how quickly your body uses energy

6. Leptin Theory Leptin- protein hormone secreted by fat cells
Too much leptin causes brain to increase metabolism and decrease hunger
LePTin
L= Lard (fat) PT = ProTein

7. Body Chemistry Glucose- blood sugar
Insulin- hormone secreted by pancreas, controls blood glucose
The hormone insulin converts glucose to fat.
When glucose levels drop (hypoglycemic)- hunger increases.

8. Hunger Hormones: Insulin- secreted by pancreas, controls blood glucose
Grehlin- hormone secreted by empty stomach, sends “I’m hungry” signals to brain…. “my stomach is a grehlin, I’m hungry.”
Orexin- secreted by hypothalamus, makes you hungry… “T-orexin search for food.”
Leptin- protein hormone, secreted by fat cells, too much = metabolism increases, hunger decreases
PYY- digestive tract hormone, sends “I’m not hungry” signals to brain…..

9. Textbook Notes: Physiology of Hunger:

10. The Physiology of Hunger
Contractions of the stomach
Washburn study

11. The Physiology of Hunger Body Chemistry and the Brain
Glucose
Insulin
Hypothalamus
Lateral hypothalamus
orexin
Vetromedial hypothalamus

12. The Physiology of Hunger Body Chemistry and the Brain
Appetite hormones
Ghrelin
Obestatin
PYY
Leptin
Set point
Basal metabolic rate

14. Psychological Aspects of Hunger
Externals v. Internals
Externals: stress, smells, food being in front of you
Internals: motivated by internal cues, empty stomach, feelings of hunger
We’re a mix of both
The Garcia Effect/ Garcia’s Taste Aversion- classical conditioning, you become sick (UR) after eating spoiled oysters (UCS), you wont eat them again, you avoid all oysters (CS)

15. Taste Preferences: Biology & Culture:
Tense/depressed/Stressed crave carbs (starchy, carb foods)…. Carbs boost serotonin = calming effect (“Serotonin flavored mash potatoes ” “Serotonin flavored ice cream”).
Sweet & salty- genetic & universal
Cultural preferences- ewww dog meat!
Dairy producing cultures (milk) more people are lactose tolerance
Hot climates- spicy foods- spices keep food from spoiling
Neophobia- dislike of unfamiliar things

16. Culture and Hunger

17. Dog
Mice Wine
Fried Frog Legs
Criadillas- bull testicles.

19. Eating Disorders
DSM-V : Diagnostic & Statistical Manual for Mental Disorders; classifies, categorizes disorders, symptoms, describes & defines, NO CAUSES, NO TREATMENT
Disorder UMAD?
Unjustifiable
Maladaptive (harmful)
Atypical
Disturbing (disrupts functioning)
Feeding & Eating Disorders:
Anorexia Nervosa
Bulimia Nervosa
Binge Eating Disorder- binging, uncontrollable , distressed/upset after the binge
Pica- eating nonedible things, like the couch, bricks, hair

20. Anorexia Nervosa
Starve themselves to below 85% of their normal body weight.
See themselves as fat, preoccupied w/food
Vast majority are woman (9/10)
Develops in adolescence
Family= competitive, high achieving, protective
Beings with a weight loss diet
Click on the woman to watch a case study of an anorexic.

21. Bulimia Nervosa
Characterized by binging (eating large amounts of food at once) and purging (getting rid of the food: vomiting, laxatives, excessive exercise).
More common than anorexia
Mostly women in their late teens, early 20s
Preoccupied w/food, fearful of becoming overweight, depressed, anxious
Weight fluctuates w/in and above normal ranges
Family = alcoholism, obesity, depression
Begins after a restricted diet has been broken

22. Eating disorders (Anorexia & Bulimia) …
Mothers tend to be focused on their own weight, and also on daughter’s weight & appearance
Mostly women in weight conscious cultures
In British study: men more likely to be overweight; women more likely to perceive themselves as overweight

23. Textbook Notes: Psychology of Hunger:

24. The Psychology of Hunger Taste Preferences: Biology and Culture
Genetic: sweet and salty
Neophobia
Adaptive taste preferences

25. The Psychology of Hunger Eating Disorders
Anorexia nervosa
Bulimia nervosa
Binge-eating disorder

26. Level of Analysis for Our Hunger Motivation

27. Level of Analysis for Our Hunger Motivation

28. Level of Analysis for Our Hunger Motivation

29. Level of Analysis for Our Hunger Motivation

31. Obesity
Severely overweight to the point where it causes health issues.
Mostly eating habits but some people are predisposed towards obesity.
Click on the pictures to see some case studies on obesity.

33. Textbook Notes: Obesity:

34. Obesity and Weight Control
Historical explanations for obesity
Obesity
Definition
Statistics
Obesity and life expectancy

35. Obesity

36. Obesity

37. Obesity and Weight Control The Social Effects of Obesity
Weight discrimination
Psychological effects of obesity

38. Weight Discrimination

39. Weight Discrimination

40. Obesity and Weight Control The Physiology of Obesity
Fat Cells

41. Obesity and Weight Control The Physiology of Obesity
Set point and metabolism

42. Obesity and Weight Control The Physiology of Obesity
The genetic factor
The food and activity factor
Sleep loss
Social influence
Food consumption and activity level

43. Obesity and Weight Control Losing Weight
Realistic and moderate goals
Success stories
Attitudinal changes

44. Crash Course Review Book 2nd Ed.: OBESITY

45. Obesity: (Notes from Crash Course Review Book 2nd Ed.)
2/3 USA adults = overweight
½ of that group = obese
1/6 USA kids (6-19 yrs old) = overweight
Obesity  heart disease, diabetes, kidney failure, cancers
300K USA adult deaths attributable to obesity

46. Obesity: (Notes from Crash Course Review Book 2nd Ed.)
Factors in becoming overweight & obese:
Environment: abundant, easily obtainable high-fat, high-calorie foods: in last 20 yrs, avg. daily caloric intake has increased 10% (men) & 7% (women)
USA sedentary lifestyle: 4/10 never exercise
Lack of adequate sleep  increases production of ghrelin (appetite-increasing hormone) & decreases production of leptin (appetite- suppressing hormone)
Genetic predispositions to obesity: people w/family history of obesity are 2-3X more likely to be obese