, in general , the history of the polycymographic system is extremely interesting, kleitmand and azirinskyists who put electrodes on a cat’s head and noticed that she had different brain activity in different phases of sleep and became from... based on the fact that this is how brain activity was discovered, when we say that slow-wave and fast-wave sleep, yes, that is, it started from neurophysiologists who studied exactly activity, it was these waves that were already put together, that it was good to see how relaxed the muscles were in order to understand what phase of sleep it was, how the eyeballs moved, in order to understand, again , what phase of sleep a person was in, from this, strictly speaking startupology as a science, as an industry. sleep has been studied very little, yes, more and more new discoveries are appearing, they will appear, due to the fact that our visualization abilities are improving, that is, we have a functional mri, where we can look at activity certain areas of the brain, in the best state during sleep, are studied in neurobiology, genetics, epigenetics are s