1. The Physiology of Hunger Adam Novajovsky and Sam Heller 5th Hour AP Psychology

2. Our Stomach When our empty stomach contracts, our brain senses this and realizes that it is hungry. Not the only thing that causes hunger, as rats without stomachs still get hungry, Cannon And Washburn Study http://www.youtube.com/wat ch?v=L3abZswA5XYhttp://www.youtube.com/wat ch?v=L3abZswA5XY to 25

3. Blood Chemistry Our blood chemistry has a large impact on our hunger. Depending on the glucose levels in our blood, the hypothalamus in our brain controls hunger sensations. Glucose Hunger IfThen

4. Blood Chemistry HormoneTissueResponse Orexin increase Hypothala mus Increases hunger Ghrelin increase Stomach Increases hunger Insulin increase Pancreas Increases hunger Leptin increase Fat cells Decreases hunger PPY increase Digestive tract Decreases hunger Hormones are released into our blood, and our hypothalamus then either increases or decreases our hunger depending on those hormones. Leptin Molecule http://www.youtube.com/ watch?v=yk3vjA7o_NI

5. Hypothalamus The largest component in hunger is the hypothalamus. It reads blood chemistry and notices changes in hormone levels, then changes our hunger based on that.

6. How it functions One theory states that it is like a thermostat, and when our weight is not at the proper set point, it increases/decreases our hunger to compensate. The other theory states that the hypothalamus registers increases in leptin from fat cells, then adjusts our hunger from there.

7. Bringing on Hunger The lateral hypothalamus, which surrounds the hypothalamus, is what makes us hungry. When stimulated, animals eat, when damaged, they don’t.

8. Stopping Hunger The ventromedial hypothalamus, is in the lower middle part of our hypothalamus, stops hunger. When stimulated, animals stop eating, when damaged, they don’t stop.