PSYC 1315 1st Edition Lecture 22 Outline of Last Lecture I Temperament II Infant attachment III Socioemotional development IV Erickson s Theory V Parenting styles VI Moral development VII Kohlberg s Theory VIII Adolescence IX Adult development X Island of Okinawa XI Biological theories of aging XII The aging brain Outline of Current Lecture I Motivation II Theories of motivation III Biology of hunger IV Biology of obesity V Disorder eating These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute Current Lecture I II III Motivation is the force that moves people to behave think and feel the way they do a Motivation energizes directs and sustains behavior i sustains behavior distinguishes motivated from unmotivated behaviors reflexes b There are several theories of motivation Theories of Motivation a Evolutionary Approach emphasizes the role of instincts b Instinct an innate unlearned biological pattern of behavior that is assumed to be universal throughout a species i Typically an instinct is set in motion by a sign stimulus something in the environment that turns on a fixed pattern of behavior ii Instincts are easily identified in animals what about humans c Drive Reduction Theory focuses on motivation through the constructs of drive and need Suggests that as a drive becomes stronger we are motivated to reduce it i Drive an aroused state of tension that occurs because of a physiological need Pertains to a psychological state ii Need a deprivation that energizes the drive to eliminate or reduce the deprivation Pertains to physiological state iii You may have a need for water but it is the feeling of being thirsty that drives the behavior iv The goal of drive reduction is homeostasis d Optimum Arousal Theory suggests that there should be a level of arousal that is ideal for facilitating goals i Ever been so anxious high arousal that you performed poorly ii Ever been so indifferent low arousal that you performed poorly iii Yerkes Dodson law performance is best under conditions of moderate arousal rather than either low or high arousal iv Overlearning means learning to perform a task so well that it becomes automatic despite arousal level 1 Navy SEALS overlearn combat techniques Biology of Hunger a The physiological state of being hungry has often been used as a path toward understanding a variety of human motivations b Gastric signals Cannon and Washburn 1912 i Stomach contractions are closely associated to hunger pangs Growling signals that we need to increase food intake ii Cholecystokinin CCK aids in digestion travels to the brain through the blood stream and signals that we need to decrease food intake IV c Blood Chemistry three chemical substances play a major role in hunger eating and satiety i Glucose blood sugar is crucial for hunger because the brain critically depends on sugar for energy 1 One set of sugar receptors in the brain triggers hunger when sugar levels fall too low 2 Another set of sugar receptors in the liver stores excess sugar and releases it into the blood when needed ii Insulin plays a role in glucose control 1 When we eat complex carbs like bread and pasta insulin level go up and fall of gradually 2 In contrast when we consume simple sugars such as candy insulin levels rise but decrease rapidly iii Leptin released by fat cells decreases food intake and increases metabolism Makes you not feel hungry 1 First discovered in ob mice which lacked fat cells that produced leptin d Hunger and the Brain i Hypothalamus involves in regulating hunger body temperature etc 1 Lateral hypothalamus outer layer is involved in stimulating hunger 2 Ventromedial hypothalamus located toward the middle is involved in reducing hunger and restricting food intake ii Neurotransmitters e Obesity and Eating Behavior i Obesity is a global issue ii 60 of Americans are overweight 1 3 of those individuals are obese iii If the current trend continues research projects that 86 of Americans will be overweight by 2030 iv The number of people overweight around the world is 20 higher than the number suffering from hunger v Researchers examine the motivation because obesity because it involves eating when one is not in need of nutrition Biology of Obesity a Factors that influence obesity i Genetics as seen in the ob mice gene mutations 1 Only 10 of children who do not have obese parents become obese whereas 40 of children who have one obese parent become obese and 70 of children who have two obese parents become obese V ii Set point the weight maintained when the individual makes no effort to gain or lose weight 1 Your set point is determined by the number of fat cells stored in the body 2 Consequently an obese person has to eat more to feel satisfied a Normal weight 10 20 billion fat cells b Obese weight over 100 billion fat cells b Obesity and Eating Behavior i Psychological Factors 1 In the past the focus was on a emotional state b external food cues 2 Current research is focusing on a time and place cues b sugar and fat content ii Brain Wansink 2005 2013 examined the factors that influence how much food people eat and found that the size of the plate influenced food intake iii Research on mindless eating 1 Subjects given a can of chips with every 7th chip red other subjects received a regular bag of chips Disorder Eating a Anorexia Nervosa an eating disorder that involves the relentless pursuit of thinness through starvation i More common among females 0 5 3 6 of Americans ii Main characteristics 1 Less than 85 of normal weight 2 unsupported fear of gaining weight 3 distorted body image 4 amenorrhea iii Can lead to 1 Growth of fine hairs all over the body 2 Thinning of bones and hair 3 Severe constipation 4 Low blood pressure 5 Damage to the heart and thyroid b Bulimia Nervosa is an eating disorder in which an individual typically female consistently follows a binge and purge eating pattern i More common among females 1 4 of Americans ii Purges by self induced vomiting or laxatives iii Because bulimia occurs within a normal eight range the disorder is often difficult to detect iv Bulimia can lead to 1 chronic sore throat 2 kidney problems 3 dehydration 4 gastrointestinal disorders 5 dental problems v Often have very high standards but low self esteem c Causes of Anorexia and Bulimia i Sociocultural media images of very thin women and family pressures This affects both disorders 1 This leads many