“There are only a few things that are so important for your body that there is a completely innate disk to get it if you fall into deficiency,” said Knight. “Oxygen, food, water and sodium.”
However, animals like us do not experience the desire for salt as a powerful, controlling drive, just like we with oxygen, food and water. Sensors signal salt levels to the brain; In addition to OVLT and SFO, sensors in the heart detect the extension of atrials and cells. But when we need, there is no analogous salt, the way the stomach rises to food or outline throat, cries into the water. Instead, the taste and brain reward trails in the need for salt consumption. “The taste of salt is bimodal,” said Knight. “It tastes good in low doses; with high doses it tastes disgusting, like drinking sea water.”
Imagine the need to eat a immense bag of potato chips. If the body needs salt, these tokens will cause that the tide of a pleasant dopamine has flooded the brain. If the body does not need salt, the dopamine drip disappears. “It’s practically learning to strengthen,” he said Yuki eyeA neurobiologist from the California Institute of Technology, who examines how the body maintains homeostasis. “More dopamine means repetitive behavior.”
Everyone wants differently
Scientists monitoring the river collect data and then have a choice whether to act on the basis of their findings. Similarly, only because the brain measures the level of sodium blood does not mean that it must act on the basis of this information.
Take thirteen Elena Grachaava squirrels. GachevaThe neurophysiologist from the Yale School of Medicine, studies these rodents, from North American green operate, to understand how specific regions of the brain control their desire. She said that the thirteen lined squirrel is ground for this perfect model, because she hibernated for over half a year, without eating or drinking. “They are like monks,” said Gacheva. “They do not go outside for eight months. They have no water in the underground hole.” How do they not become thirsty?
CC-By 2.0 Via Wikimedia Commons
It is not that squirrels do not need water. Yes. Their bodies call for it. But according to Gacheva’s research, during hibernation, their brain ignores the signals of the body.
In mammals, a decrease in blood water level (which means a simultaneous raise in salt concentration, all things are even) causes two combined processes. The hypotalamus pumps out the vasopressin of the hormone, which tells the kidneys to stop water, and not get it as urine, and SFO begins the desire to direct the animal to drink. However, while the ground squirrels are hibernating, their Vasopressin levels jumpBut the animal still doesn’t drink. “The vasopressin circuit was normal, but the desiring neurons were adjustable,” said Gacheva. “These two paths are disconnected.” The body tries to stop the water it has, but it does not work to absorb more.
The logic of the disturbed circumference is extremely powerful. “Even if you wake them up during hibernation, they won’t drink,” said Gacheva.
The basic network that Grachiva studies in squirrels is universal in mammals, up to people. But the same neurological logic does not lead to the same behavior. People drink a glass of water when they are thirsty. Cats and rabbits mainly come from food that they eat. Camels can burn their fat stores for water (which produce carbon dioxide and water), but they also consume its galns and store it in the stomachs when they need it later. Sea otters can drink ocean water and that is, urine excretion more salt than the water in which they flow; They are the only sea mammals that actively do it.
The way each animal manages water and salt is specialized in the ecosystem, lifestyle and selective pressure. The question “What does it mean to be thirsty?” There is no single answer. We want each of us in our own way.
Original story reprinted with consent from How much warehouseeditorly independent publication Simons Foundation whose mission is to raise public understanding of science by covering the development of research and trends in mathematics and physics and life sciences.