The human brain has been a mystery for those who try to understand it. It ultimately controls all functions of the human body such as reflexes, the heart, thoughts and feelings. A new study conducted at Ohio State reports that the human brain may also be responsible for nausea.”This (the brain) is one of the most investigative fields in medicine,” said Richard Rogers, professor of neuroscience for the College of Medicine.Rogers, along with colleagues Gerlinda Hermann, research assistant professor of neuroscience, and Greg Emch, OSU graduate student in neuroscience, have found that a chemical produced by the immune system directly stimulates the part of the brain controlling digestion.Tumor necrosis factor (TNF), may be the link connecting the immune, brain and digestive systems to produce the perception of illness in the body. TNF has also been associated with anorexia, vomiting and gastrointestinal stasis.Rogers’ study explains the relationship between the brain and the digestive system.Thousands and thousands of people are affected, he said those most susceptible to the release of TNF are people with HIV, Lupus and others. From the common cold to severe cancer, the chemical TNF can create the feeling of nausea.”It really degrades their quality of life. It can actually be fatal,” Rogers said. This system is the activation of a immune function. Cells in the system are then activated and coordination of the attack is controlled by the release of the hormone TNF. By using research and data found 10 years ago, Rogers and his colleagues have found that the brain stem may actually be the problem.”Neurons are extremely sensitive,” he said.According to Rogers, prior to the first hint of illness, the immune system readies itself for attack by sending out the hormone TNF.Earlier studies conducted by Rogers and his colleagues found that TNF suppresses movement of food through the stomach and acts directly upon neurons in the part of the brain stem called the nucleus of the solitary tract (NST). The researchers showed that when TNF acts on NST neurons, they cause the stomach to stop a digestion condition called “stasis.” The dramatic stomach relaxation is perceived as nausea.Rogers, Hermann and Emch, published their work in September issue of the American Journal of Physiology, Gastrointestinal and Liver Physiology.