Motivation and Emotion: The Case of D.W.

1. Chapter 5 Motivation and Emotion

2. The Case of D.W. • 1930s • young child subsisted on diet of salt and water • Ate salt directly, drank water at any opportunity • became agitated if denied • Died following attempt to control diet • Salt need due to cancer of adrenal glands

3. Motivation • The factors that cause organisms to behave the way they do • the “why” of psychology • Hedonism • the basic motivation to seek pleasure and avoid pain • Motivation is closely linked to emotion • affective psychological experience • associated with arousal

4. Motivation • Motivating factors come from a variety of sources: • evolutionary • physiological • psychological • sociolocultural

5. Physiological Basesof Motivation • Neuroendocrine System

6. Neuroendocrine System • Communication system • Endocrine glands and brain structures • network of neurons that communicate with hormones through the circulatory system

7. Hormones • Biologically active chemicals • e.g. peptide, protein or steroid • Bind to target tissues around the body • Regulate hunger and thirst • Influence development of primary and secondary sexual characteristics • Influence mating behaviors • Regulate immune function

8. Neuroendocrine Regulation • Hypothalamus • structure at the base of the brain • regulates sexual behavior, temperature, hunger and thirst • monitors blood levels of hormones and nutrients • directs other glands to produce appropriate hormones

10. Homeostasis • The maintenance of a balanced system through self-regulation • Homeostasis is maintained through negative feedback • movement away from a set point results in compensatory responses to restore the balance

11. 98 set point 98 set point 98 set point Temperature:An Example of Homeostasis Involuntary Mechanisms Sympathetic: Vasoconstriction Shivering

12. 98 set point 98 set point 98 set point Temperature:An Example of Homeostasis Parasympathetic: Vasodilation Sweating Involuntary Mechanisms

13. 98 set point 98 set point 98 set point Temperature:An Example of Homeostasis Voluntary Mechanisms CNS: Put on jacket

14. 98 set point 98 set point 98 set point Temperature:An Example of Homeostasis CNS: Take off jacket Voluntary Mechanisms

15. Behavioral Regulation • Adaptive behaviors that help achieve a homeostatic state • e.g. eating important nutrients, drinking water

16. Regulation of Water and Salt • Maintain salt balance similar to ocean • Two types of thirst: • Osmotic Thirst • when concentration of solutes in tissues exceeds 0.15M • can result in specific appetite for water(e.g. DW) • Hypovolemic thirst • results from abnormally low blood volume

17. Drive States • Primary Motivation • Instinctive or biologically motivated behavior • e.g. fixed action patterns • Drive Reduction (Clark L. Hull) • motivation based on reducing needs and restoring homeostasis

18. Acquired Motivation • Not all motivating factors are instinctive • Acquired Motivation: • Motives learned over a lifetime • e.g. money as reward • Sometimes called Incentive Motivation • Incentives: goals that motivate behavior

19. Eating as Motivated Behavior • Many factors lead to selection and ingestion of foods • Genetic • Psychological • Sociocultural

20. Closed Feeding Systems • Usually found in animals with simple nervous systems • Reflexive responses to a narrow range of foods • e.g. fly • feeding initiated by receptors on leg • only feeds on specific foods

21. Open Feeding Systems • Wide variety of food choices • Animals must learn what is good to eat • Omnivore’s Paradox • greater selection of food increases available nutrition but also increases likelihood of poisoning • omnivores are typically neophobic • suggests instincts still important in food choice

22. Nutritional Wisdom • Innate predisposition to make adaptive food choices • Infants • innate preference for sweet • dislike bitter and sour (indicative of poison)

23. Taste Cues • Rats prefer familiar tastes • Will switch to new foods if familiar foods are nutritionally deficient (e.g. reduced thiamine) • We tend to eat foods that made us feel good in the past

24. Feeding Jags • Eating one food type for extended periods • e.g. kids eating peanut butter sandwiches • jag ends when switch to another food type • May be a response to a specific nutritional deficiency • Variety increases nutritional intake • switching foods because of new deficiency

25. Sensory-Specific Satiety • Get full eating one type of food during meal • Can continue eating if offered another food (e.g. dessert) • Increases variety of intake

26. Evolution of Food Selection • Biocultural Evolution • selection of certain foods increases the fitness of individuals in a culture • e.g. food combinations • Recipes and preferences transferred from one generation to next • Meme: extragenetic information transfer

27. Genetics • Lactose Intolerance • due to recessive gene leading to lower levels of lactase • common in Asian and some African populations

28. Brain Mechanisms • Hypothalamus

29. Hypothalamus and Eating • Dual-Center Model of Hunger • Damage to the Lateral Nucleus of the Hypothalamus in rats results in aphagia (loss of eating) • Damage to Ventromedial Nucleus of the Hypothalamus results in hyperphagia and obesity

30. Hypothalamus and Eating • Dual-Center Model of Hunger • Lateral Nucleus is the “start eating” center • stimulating leads to onset of eating • when damaged, rats will not start eating • Ventromedial Nucleus is the “stop eating” center • when damaged, rats will not stop eating

31. Problems with theDual Center Model • Stimulating the Lateral Nucleus of the Hypothalamus leads to a wide variety of motivated behaviors • drinking • copulation

32. Problems with theDual Center Model • Damaging the lateral hypothalamus also damages other pathways • especially dopamine-rich nerves that come from areas associated with arousal and pleasure

33. Problems with theDual Center Model • However, • Lateral Hypothalamus interacts with brain structures involved in feeding • also interacts with pancreas • Calling it the “start-eating” center was too simple

34. Problems with theDual Center Model • Ventromedial Hypothalamus • Ventromedial-damaged rats only overeat foods that taste good • Rats gain weight, even if put on a strict diet • produce abnormally high levels of insulin - leads to greater fat storage

35. Insulin and Blood Glucose • Homeostasis of blood glucose levels • Increased blood glucose following meal leads to an increase in insulin from pancreas • Results in storage of glucose as glycogen or fat • Low glucose levels leads to an increase in glucagon from pancreas • Results in conversion of glycogen back to glucose

36. Pleasure • Humans are genetically predisposed to seek pleasure and avoid pain • promote survival and reproduction

37. Brain Mechanisms for Pleasure • Electrical Stimulation of the Brain (ESB) • Simulating medial forebrain bundle (MFB) appears to be pleasurable to rats • Stimulating other brain structures can also be effective • Rats prefer to stimulate their brains over eating

38. Pleasure Seekingin Humans • ESB in humans results in reports of pleasure • Similarities to crack cocaine ingestion • crack activates dopamine receptors that have been implicated in ESB in rats

39. Acquired Pleasures • Not all behaviors are motivated by primary needs • Acquired pleasures can act as secondary reinforcers • Acquired pleasures need not be necessary for survival • But, you must meet the primary needs first

40. Hierarchy of Needs • Abraham Maslow • once biological needs are met, humans can gain social, esteem and self-actualization needs

41. Intrinsic vs. Extrinsic Motivators • Intrinsic Motivation • motivation to achieve self-satisfaction • e.g. simple curiosity • Extrinsic Motivation • motivation to meet the standards of others • e.g. working for money

42. Intrinsically-Motivated People • Task-oriented • Gain satisfaction from task, not rewards • Often achieve more than those motivated by extrinsic factors • Display: • A quest for mastery • A drive to work • Less interested in competition

43. Overjustification Effect • A decrease in intrinsic motivation when an extrinsic motivator is offered • e.g. 3- to 5-year-olds show less interest in school activities when they were rewarded than before

44. Need for Achievement • Motivation to accomplish a challenging task quickly and effectively • can be measured as a personality characteristic • People with a high need for achievement: • work harder • are more future oriented • are willing to delay gratification • tend to choose realistic goals, not challenging goals

45. Emotions • Are emotions innate? • Darwin: The Expression of Emotion in Man and Animals • Emotional behavior is adaptive • Emotions organize behavior and communicate intent

46. Emotions • Human emotional displays are similar to other animals

47. Emotion in Humans • Basic emotions: • Anger • Disgust • Fear • Interest • Joy • Surprise • Sadness

48. Expressions of Emotion • Cultural differences • not all cultures describe emotions in the same way

49. Expressions of Emotion • Facial Expressions • all cultures can display and recognize emotions in a similar manner

50. Expressions of Emotion • Facial Expressions • cultures differ in acceptability of emotional expression • e.g. Japan: polite smile as substitute for display of disgust