Researchers found that smells or sights of food make the brain prepare the body before a meal. Special neurons in the hypothalamus, called POMC neurons, become active when food is expected.
These neurons use small pockets of glycogen, the bodys stored energy, to work during anticipation. In mice, showing food behind a wire mesh activated glycogen synthase, the enzyme that makes glycogen. Mice without this enzyme in POMC neurons approached food less, spent less time eating, and did not make insulin before feeding. Removing the enzyme in adult mice caused the same problems.
Difficult words
- neuron — cell that sends signals in the brainneurons
- hypothalamus — part of the brain that controls body
- anticipation — feeling or state before something happens
- glycogen — stored form of sugar used for energy
- enzyme — protein that helps chemical reactions happen
- insulin — hormone that helps control blood sugar
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Discussion questions
- Have you ever smelled food and felt hungry before eating? What happened?
- Why do you think the brain prepares the body before a meal?
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