The Activation Of The Sympathetic Nervous System Results In
Hacking the Nervous System to Heal the Body. Kevin Tracey, a neurosurgeon based in New York, is a man haunted by personal events a man with a mission. My mother died from a brain tumor when I was five years old. It was very sudden and unexpected, he says. And I learned from that experience that the brain nerves are responsible for health. This background made him a neurosurgeon who thinks a lot about inflammation. He believes it was this perspective that enabled him to interpret the results of an accidental experiment in a new way. In the late 1. 99. Books/B0/E27R7642/MAIN/images/1508_Autonomic_Control_of_Pupil_Size.jpg' alt='The Activation Of The Sympathetic Nervous System Results In' title='The Activation Of The Sympathetic Nervous System Results In' />Tracey was experimenting with a rats brain. Design Patterns In Java Pdf. Wed injected an anti inflammatory drug into the brain because we were studying the beneficial effect of blocking inflammation during a stroke, he recalls. Install Sap Automation Activex Controls there. Your autonomic nervous systemthe part of your nervous system responsible for involuntaryvital functions such as the beating of your heart, digestion, elimination. Shift Toward the Social Engagement System. The ventral vagal system is involved with most aspects of social contact and pleasure. It guides eye contact, hearing. We were surprised to find that when the drug was present in the brain, it also blocked inflammation in the spleen and in other organs in the rest of the body. Yet the amount of drug wed injected was far too small to have got into the bloodstream and traveled to the rest of the body. After months puzzling over this, he finally hit upon the idea that the brain might be using the nervous system specifically the vagus nerve to tell the spleen to switch off inflammation everywhere. It was an extraordinary idea if Tracey was right, inflammation in body tissues was being directly regulated by the brain. Communication between the immune systems specialist cells in our organs and bloodstream and the electrical connections of the nervous system had been considered impossible. Netperf Windows 7 Download on this page. Now Tracey was apparently discovering that the two systems were intricately linked. The first critical test of this exciting hypothesis was to cut the vagus nerve. When Tracey and his team did, injecting the anti inflammatory drug into the brain no longer had an effect on the rest of the body. The second test was to stimulate the nerve without any drug in the system. Because the vagus nerve, like all nerves, communicates information through electrical signals, it meant that we should be able to replicate the experiment by putting a nerve stimulator on the vagus nerve in the brainstem to block inflammation in the spleen, he explains. Thats what we did and that was the breakthrough experiment. The Wandering NerveVagus is Latin for wandering and indeed this bundle of nerve fibers roves through the body, networking the brain with the stomach and digestive tract, the lungs, heart, spleen, intestines, liver and kidneys, not to mention a range of other nerves that are involved in speech, eye contact, facial expressions and even your ability to tune in to other peoples voices. It is made of thousands and thousands of fibers and 8. Not all vagus nerves are the same, however some people have stronger vagus activity, which means their bodies can relax faster after a stress. The strength of your vagus response is known as your vagal tone and it can be determined by using an electrocardiogram to measure heart rate. Every time you breathe in, your heart beats faster in order to speed the flow of oxygenated blood around your body. Breathe out and your heart rate slows. This variability is one of many things regulated by the vagus nerve, which is active when you breathe out but suppressed when you breathe in, so the bigger your difference in heart rate when breathing in and out, the higher your vagal tone. Research shows that a high vagal tone makes your body better at regulating blood glucose levels, reducing the likelihood of diabetes, stroke and cardiovascular disease. Low vagal tone, however, has been associated with chronic inflammation. As part of the immune system, inflammation has a useful role helping the body to heal after an injury, for example, but it can damage organs and blood vessels if it persists when it is not needed. Having found evidence of a role for the vagus in a range of chronic inflammatory diseases, including rheumatoid arthritis, Tracey and his colleagues wanted to see if it could become a possible route for treatment. The vagus nerve works as a two way messenger, passing electrochemical signals between the organs and the brain. In chronic inflammatory disease, Tracey figured, messages from the brain telling the spleen to switch off production of a particular inflammatory protein, tumour necrosis factor TNF, werent being sent. Perhaps the signals could be boosted Image by Alila Medical Media Shutterstock. Stimulating Results. Tracey designed the trial with his collaborator, Paul Peter Tak, professor of rheumatology at the University of Amsterdam. Tak had long been searching for an alternative to strong drugs that suppress the immune system to treat rheumatoid arthritis. The bodys immune response only becomes a problem when it attacks your own body rather than alien cells, or when it is chronic, he reasoned. So the question becomes how can we enhance the bodys switch off mechanismWhen Tracey called him to suggest stimulating the vagus nerve might be the answer by switching off production of TNF, Tak quickly saw the potential and was enthusiastic to see if it would work. Vagal nerve stimulation had already been approved in humans for epilepsy, so getting approval for an arthritis trial would be relatively straightforward. And patients on the trial had transformative experiences. The results are still being prepared for publication but Tak says more than half of the patients showed significant improvement and around one third are in remission in effect cured of their rheumatoid arthritis. Sixteen of the 2. Some are now entirely drug free. We have shown very clear trends with stimulation of three minutes a day, Tak says. Tak suspects that patients will continue to need vagal nerve stimulation for life. But unlike the drugs, which work by preventing production of immune cells and proteins such as TNF, vagal nerve stimulation seems to restore the bodys natural balance. It reduces the over production of TNF that causes chronic inflammation but does not affect healthy immune function, so the body can respond normally to infection. Changing the Tone. Having an electrical device surgically implanted into your neck for the rest of your life is a serious procedure. But the technique has proved so successful and so appealing to patients that other researchers are now looking into using vagal nerve stimulation for a range of other chronic debilitating conditions, including inflammatory bowel disease, asthma, diabetes, chronic fatigue syndrome and obesity. The implications of being able to simply and cheaply improve vagal tone, and so relieve major public health burdens such as cardiovascular conditions and diabetes, are enormous. It has the potential to completely change how we view disease. If visiting your doctor involved a check on your vagal tone as easily as we test blood pressure, for example, you could be prescribed therapies to improve it. But this is still a long way off We dont even know yet what a healthy vagal tone looks like, cautions researcher Bethany Kok.