Unit 8A (Emotion is part 8B) Motivation Unit 8A (Emotion is part 8B)

Intro Motivation – need or desire that propels a behavior toward a goal Case study: Aron Ralston. Why?... …human will to live, to keep going. 4 ways psychologists approach motivation… Instinct theory – genetics, evolutionary approach Drive-reduction theory – inner & external motivations Arousal theory – stimulation, alertness Hierarchy of needs – Abraham Maslow’s triangle

Instinct theory Based on Darwin’s evolutionary theory of 150 years ago Supposedly, there’s an instinct for everything Instinct – complex behavior in a species that is unlearned Ex.: salmon swimming upstream; bird building a nest People have instincts, but seem less obvious than animals

Drive reduction theory A. L. Washburn and his crazy stomach experiment He swallowed a balloon, inflated it, recorded when he felt hunger. Conclusion… …stomach contractions cause hunger feelings. Your body matters. Brain Hypothalamus has “hunger controls” Electric shock I’m hungry! Gives out orexin hormone  I’m hungry! Lower-mid hypothalamus is “hunger-off switch” (on=not hungry)

Drive reduction (cont.) Hormones - ILOOP Insulin – regulates blood sugar Leptin – causes brain to change metabolism Orexin – hypothalamus – I’m hungry! Obestatin – stomach – I’m full! PYY – intestines – I’m full! Balance Set point – your body’s natural weight Eating matters Exercise matters BMR – basal metabolic rate – how we burn energy while at rest Semi-starved people – drop ¼ of wt., then level off at 75% BMR

Drive reduction (cont.) Psychology of hunger… If people eat but don’t remember… 20 minute amnesia – they’ll eat again! In a group? Depressed? More with group or depressed. Cravings? Fatty and salty foods (genetics? Culture?) Portion size matters – smaller plates & utensils

Eating disorders Anorexia nervosa Binge-and-purge ½ the time Person is unable to see they’re skinny Women, ¾ of the time Upper-middle class Bulimia nervosa Binge-and-purge Person usually has a more normal weight (hard to recognize) Binge eating disorder Binge eats buts does not purge All: often followed by depression, guilt

Cont. Why? Culture Africa – larger is attractive Western nations – skinny is attractive History Bigger meant health/$/babies. Today, obesity is seen as bad. Gender Women can be more critical of themselves (?) Barbie factor… …Expectations

Cont. Risks of obesity Heart problems, diabetes, BP, gall stones, arthritis, some cancer, Alzheimer’s in women, shame. U.S. – highest obesity rate in world Physiology Fat cells are like balloons, but also divide. This makes it hard to keep the weight off. Just not eating…body adjusts BMR. Genetics “Fidgetiness”avoiding obesity. Sitting still obesity ID twins weight correlates at .74 (high) Obese parents? Boys 3X likely, girls 6X likely to be obese

Cont. Environment Lack of sleep increases chance of obesity Fast food, cooking in oil, sugar, TV time (2 hrs. 23% increased chance) Amish – low obesity rates (1 out of 9) Tips to avoid obesity Eat moderately Set reasonable goals (10% over 6 months) Eat right & exercise