CH 11 MOTIVATION THE PHYSIOLOGY OF HUNGER Body chemistry different metabolic rates o May be due to early childhood eating habits o Genetic Brain o Hypothalamus Lateral region brings on hunger Destroyed starve Ventromedial region depress hunger Destroyed continue to eat Role of Ghrelin o Hormone that increases before meals and decreases after o Linked to appetite o PYY chemical suppresses appetite in mice for a short time o Lectin secreted by fat cells seems to diminish the reinforcing impact of food Set point hypothesis diff people have a set point set weight that they gravitate back to if they gain or lose weight Not fixed in stone changes in adult life span But we do have a set point once we achieve a certain weight our body tries to keep it there may be determined by body chemistry genetics metabolic rate etc o of fat cells when we lose weight we don t lose fat cells they just get smaller in size more cells tiny When the cells become small they send out signals that say that you re hungry because they ve shrunk Can signal metabolism to slow down challenges weight loss yo yoing in weight 85 gain it back Long term weight loss difficult for us as a culture Body chemistry set points External incentives o Smell of food walking by a restaurant and smelling the food and wanting it even if you ate already o Visual of food seeing an ad for pizza order pizza o Some are more susceptible to the external signals might be due to Eating habits established over the life span Taste preference Culture o We learn to like different foods o Children reluctant to try new foods Why Adaptive cautious avoid any potentially toxic new foods Need to try foods well over 30 times before they actually eat it OBESITY o Drawn towards sweet things o When food is available we eat it Because our body thinks we may have to face famine historical drive o Genetics and heritability Weight correlates around 74 Concordance rate of identical twins 74 similarity Concordance rate in fraternal twins 32 o Fat cells o Culture Becker et al Fiji Adolescent Girls Study 2002 Ideal beauty heavy Western television came to Fiji during the course of the study Tv in every household while doing the study o Interviewed girls gave them the EAT eating attitudes test Use for people with eating disorders Increase in eating disorders body image disorders post western tv exposure Sigma of Obesity o Obese children are viewed negatively by peers o Gender and obesity o Obese women gender interaction with obesity Stronger effects for obese women o Receive lower salaries o Victims of discrimination o Less likely to marry o Often the victims of weightiest comments o Study on pre school children found that children didn t want to sit with heavier students o Asked to tell what the heavier kids ate said gross foods because they re gross people ate poop dirt sticks etc o Media consumption sedentary EATING DISORDERS o Anorexia o 1 50 girls affected only about 5 15 are boys o more common in Caucasian americans than in African americans o peaks in early adolescence o symptoms appear before menarchy first period if starving is severe enough the period ovulation doesn t occur Need a certain amount of body fat to support pregnancy Can affect fertility permanently if ovulation does not occur for an extended period Fat spurt natural weight gain in adolescence To support pregnancy and lactation Girls tend to hit puberty 2 5 years before boys o Might contribute to the development of anorexia seeing that the boys are thinner and smaller than they are o 4 die highest death rate of all the mental disorders anorexia can be life threatening Damage to the heart muscle Starve lose muscle incl heart muscle o What role does the media play There are girls with anorexia that give ADVICE to other girls on HOW to maintain an anorexic life style how to trick your friends and family eating lettuce with mustard ice cubes sucking on a rock exercising in the shower etc THIN models in the media o Kat s story 26 y o now healing But physical consequences remain But WILL have osteoporosis in her 40s guaranteed Physical consequences hair fall out in chunks toenails and fingernails falling off swelling aches sore in ankles wrists etc Calcium deficiency aches and soreness Brittle bones ribs were at risk of cracking Rotten teeth need to take them all out Bowels pooped out her own stomach acid because there was no food peed herself even when she coughed couldn t control her urine o 2 3 days enema s blames only herself but in reality culture has an influence In early adolescence we don t have the cognitive ability to determine the consequences o criteria profound fear of becoming obese disturbance of body image never thin enough weight loss of at least 25 body weight refusal to maintain a healthy body weight no physical illness that would account for the weight loss beyond anorexia o Bulimia o May not be under weight o Tissue damage in the throat from vomiting stomach acid o Damage to teeth from constant acid exposure Wears out the enamel translucent appearance begin to look black o One study found 19 of college age women exhibited symptoms of bulimia Bulimia and anorexia are Under diagnosed o Can be fatal 3 9 less than anorexia Throws body chemistry off potassium Heart problem arrhythmia failure to beat heart attacks o Criteria Episodic binge purging Use abuse of laxatives Not being able to stop binge purging voluntarily Depressed mood self deprecating thoughts shame and humiliation associated with purging Repeated attempts following binging to control weight dieting Then a fall back to bingeing and purging Does society contribute to eating disorders YES What messages do we take from the media Ex little mermaid Ursula Disney villians tend to have physical standards be obese or skeletally thin Original little mermaid story young girl who has each of her sisters who get to see the world above the ocean Goes to sea witch and makes a bargain tongue gets cut off Every step she takes on land is like stepping on knives if she doesn t get the prince she loses her soul In the end she didn t get the prince and turned into sea foam Ideal body image for women in the past pale didn t have to be in the sun no muscle tone didn t have to work heavier they had money to get food LOVE Multiple styles of love John Alan Lee o Ludus Game play love Rules someone has more power than someone else who calls who the chase is more fun than the actual relationship No real intimacy commitment psychological Who