AP PSYCH Unit 8A.1 Motivational Concepts & Hunger

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1 AP PSYCH Unit 8A.1 Motivational Concepts & Hunger What is motivation? What motivates you? From what 4 perspectives do psychologists view motivated behavior?

2 Are You Motivated? Motivation - a need or desire that energizes and directs behavior towards a goal. There are very close ties between emotions and motivated behaviors. Aron Ralston Story How does his story make you feel? thismotivate you or make you feel like you ve done nothing with your life?!

3 1. Instincts & Evolutionary Psychology Instinct - A complex behavior that has a pattern in a specific species and is unlearned. Sea turtles, newly hatched on a beach, will automatically move toward the ocean. Humans: rooting, suckling, and sleeping Reflexes

4 1. Instincts & Evolutionary Psychology Is motivation simply an instinct? (Instinct Theory) Not exactly, it s a combo of psychological needs & psychological wants But yes, evolution and instinct play a role in behavior, just not motives

5 2. Drives & Incentives Instinct theory was replaced by drive-reduction theory. Drive-Reduction Theory - a physiological need creates an aroused state or a drive that motivates the organism to satisfy the need. Hunger or Thirst

6 The aim of Drive- Reduction Theory is to attain homeostasis. Homeostasis - balanced or constant internal state. The word literally means staying the same. Causes a drive Bodies temperature regulation Drives & Incentives

7 Drives & Incentives Incentive - positive or negative environmental stimulus that motivates behavior. We are not just pushed by our need to reduce drives we are also pulled by incentives. Somebody who is food deprived and smells baking bread feels a strong hunger drive and the bread becomes the incentive. Nature (inborn physiological need) vs. Nurture (incentives in the environment)

8 Some motivated behaviors can be explained by the want to be aroused. We are motivated and driven by curiosity, we are fascinated by novel or new things. Arousal Theory - Motivation aims not to eliminate arousal but to seek optimum levels of arousal. What got Aron Ralston stuck under that rock in the first place?? Boredom = lack of stimulation & arousal 3. Optimum Arousal

9 4. Maslow s Hierarchy of Needs Developed by Abraham Maslow Some needs take priority over others Thirst preoccupies you when desperately thirsty When lower needs are satisfied we focus on higher needs Hierarchy of Needs pyramid of human needs, beginning with physiological that must first be satisfied before moving higher to each tier, then up, then up

10 Maslow s Hierarchy of Needs What is selftranscendence? Are these levels universally fixed? Are they the same for every culture?

11 Maslow s Hierarchy of Needs Consider your own experiences in relation to the hierarchy. Have you ever experienced true hunger or thirst that displaced your concern for other, higher-level needs? Do you usually feel safe? Loved? Confidant? The higher tiers can become much less important in emergency situations.

12 Hunger

13 Ancel Keys Experiment Fed 36 volunteers just enough to maintain initial weight. Then cut rations in half. Body stabilized at 25% below starting weight Began conserving energy Became food obsessed All efforts were focused toward their next meal Lost interest in any activities not involving food (sex, social activities) Food and hunger has a powerful effect on us.

14 Physiology of Hunger Our stomachs contract when we feel hungry (see below) But this is only one source of hunger

15 Blood Chemistry & The Brain When our blood glucose (sugar that circulates in our blood, major source of energy for body) level drops, signals will be sent from the stomach, intestines, and liver to the brain to trigger hunger The hypothalamus triggers hunger - monitors the body s appetite hormones

16 Blood Chemistry & The Brain Damage to the hypothalamus can create weight difficulties either too much or little. LH (lateral hypothalamus triggers hunger)) vs. VMH (ventromedial hypothalamus lowers hunger) Mnemonic: Large Hunger, Lingering Hunger vs. Very Mini Hunger

17 The Appetite Hormones Insulin: Secreted by pancreas; controls blood glucose Leptin: Secreted by fat cells; when abundant, causes brain to increase metabolism and decrease hunger Orexin: Hunger-triggering hormone secreted by hypothalamus. Could we manipulate appetite hormones and treat anorexia or obesity?

18 The Appetite Hormones Ghrelin: Secreted by empty stomach; sends out I m hungry signals to the brain; decreases after meals Bypass surgery effects this Obestatin:secreted by full stomach, sends I m full signals, suppresses hunger PYY: Digestive tract hormone; sends I m not hungry signals Could we manipulate appetite hormones and treat anorexia or obesity?

19 Set Point & BMR Set point the point at which an individual s weight thermostat is supposedly set. When the body falls below this weight, a decreased metabolic rate may act to restore the lost weight The theory of the set point is not as widely believed anymore. Basal metabolic rate the body s resting rate of energy expenditure Researchers believe people reach a settling point, the level at which a person s weight settles in response to caloric intake and expenditure

20 They Psychology of Hunger Part of being hungry is knowing when our last meal occurred, and what time we normally eat at. Amnesia experiment if offered food people keep eating Psychological influences on eating behavior are most extreme when the desire to be thin overwhelms normal homeostatic pressures

21 Taste Preferences: Biology Both biology and culture play a role in food preferences. Carbs boost Serotonin levels, creating a calming effect. This leads to the label of comfort foods. Do you crave certain foods in certain stressful situations? Preferences for sweet or salty is genetically based. Some taste preferences are conditioned an acquired taste or the opposite a taste aversion

22 Taste Preferences: Culture Different cultures enjoy different foods Examples? With repeated exposure, taste appreciation for a food typically increases Are you a neophobe? Taste preferences can be adaptive hotter climates traditionally used more spice to kill bacteria Pregnancy relate nausea and cravings changing hormone levels affect taste preferences in pregnant moms

23 The Ecology of Eating Situational Eating: People eat more when they are eating with others social facilitation - explains why we may eat more during the holidays Unit Bias - Portion size Countries that offer servings in smaller sizes are thinner on average Experiment with bowl or spoon size bigger sizes mean you will take more So use a smaller plate!

24 Eating Disorders Anorexia Nervosa An eating disorder in which a person (most likely an adolescent) diets and becomes significantly (15% or more) underweight, yet still feeling fat continues to starve Bulimia nervosa an eating disorder characterized by episodes of over eating, usually high calorie foods, followed by vomiting, fasting, laxative use, or excessive exercise Binge-eating disorder significant binge eating, followed by guilt, without the purge of bulimia

25 Eating Disorders Genetics may influence susceptibility to eating disorders There are cultural factors In India, women rate their shape the closest to their actual shape In Africa, being a little larger means prosperity Generationally, the number of eating disorders have risen as 50% of women say they feel negative about their appearance

26 Gender Differences Muscle dysmorphic disorder bigorexia People with this disorder obsess about being too small and frail and undeveloped. Even if they have good muscle mass, they believe their muscles are inadequate. Men are more likely to be overweight, and women are more likely to perceive themselves as overweight

27 Media and Body Image Part of the issues with body image in today s society are what is portrayed sexy or attractive in the media People begin to idealize media portrayals which leads to dissatisfaction with personal body image If Barbie were real, she would be about 6 tall, have a 39 bust, 18 waist, 33 hips

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