1. DO NOW: HOW DO YOU KNOW WHEN YOU ARE HUNGRY? Unit 7: Lesson 2 Hunger 1

2. AIM How is hunger controlled? 2

3. Importance of hunger Maintenance of homeostasis 3

4. What triggers hunger? Hypotheses? Contraction of an empty stomach Exp: remove stomach Result: Hunger Inference: Hunger controlled by something else in addition to the stomach 4

5. Brain and Hunger Exp: Plate of food in front of a subject Observation: Depending on the location of the stimulation people ate while others did not Dual control of the hypothalamus 1. Lateral (hunger center) 2. Ventromedial (satiety center) Set point theory 5

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7. Hypothalamus set point 1. Glucostatic hypothesis: monitor glucose levels, when drop stimulates hunger 2. Lipostatic hypothesis: fat levels regulate feelings of hunger (Leptin levels) Leptin is a hormone; high level less food consumed 7

8. Eating behaviors External: more motivated to eat when see food Internal: less motivated by sight but more by internal hunger cues Environmental and social cues 8

9. Adaptive Taste Preferences Neophobia Example: cultures that use many spices on foods Spices create an environment that reduces bacterial growth on food Theory of taste preferences is based on calculation of cost and reward….thoughts? 9

10. Eating Disorders Bulimia Anorexia Nervosa Obesity 10

11. Investigations into Obesity How could we test if genetics has a role in bodyweight maintenance? Twin studies Obesity a complex condition Basal metabolic rate Weight management 11