Scientists from Columbia University (USA) in experiments on Drosophila (fruit flies) found that serotonin is a chemical that causes the body’s reaction to fear – an automatic reflex in which the body momentarily freezes in response to a potential threat.
These results offer a better understanding of the biology of reaction of fright – little-known phenomenon, which is observed in almost every animal, including humans.
“On the basis of this study it becomes clear that the rapid release of serotonin in the nervous system of Drosophila causes initial fading, commented the author of Richard Mann. And because serotonin is also in humans, the results shed light on what happens when we freeze”.
In the brain serotonin is most closely linked with the regulation of mood and emotion. But previous studies on animals have shown that it also affects the speed of movement of the animal. In this work it was important to understand exactly how this happens.
The team with the help of a special apparatus FlyWalker analyzed the steps of fruit flies in a special glass. Scientists have altered levels of serotonin and dopamine in the ventral nerve channel of the flies, which is similar to the spinal cord of vertebrates. As a result of the experiment revealed that when neurons flies aktiviziruyutsya and serotonin is released, the movement of the flies is slowed down. Whereas “silence” of these neurons, accelerates the movement of flies. Additional experiments have shown that serotonin levels can affect the walking speed of insects under different conditions.
Scientists believe that the pause in the fading important – it allows nervous system to collect information about the sudden change of environment and to decide how to react.
Although the results of the experiment are specific to fruit flies, the ubiquity of serotonin and reaction to fear give information about the chemical and molecular processes that occur when a sharp change of environment in animals and humans.