| MadSci Network: Medicine |
The sensation of growling or vibration is a result of our brains telling the stomach to digest food when food is not present. If energy levels are low (that is, if glucose levels in the blood are less than normal), the brain sends signals to the stomach telling it to digest food so more energy can be released. The stomach muscles receive the nerve impulses and start to move. However, because the stomach is hollow, the motion of the stomach resonates the air and creates the sensation of vibrations.
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