WEDNESDAY, JANUARY 13TH, 2021.-
The study notes that animals would have acquired sleep-related mechanisms before the nervous system
🖊 CODIGO ESPAGUETI 📸 Universidad Kyushu
Being able to sleep has always been linked to brain activity; however, a recent study, conducted in a Hydra vulgaris - a small cnidarium no larger than 30 millimetres - revealed that brain functions and sleep may not be related.
Scientists from Kyushu University of Japan and the Ulsan Institute of Science and Technology in South Korea conducted a study on Hydra vulgaris and found that the brain may even have developed after the need for sleep occurred.
Hydra vulgaris, the study says, has a primitive organization, lacking a central nervous system, and is still able to reach a sleep-like state.
"We now have solid evidence that animals must have acquired the need to sleep before acquiring a brain," said Taichi Q. Ito, a professor associated with research.
This new study found that several chemicals – such as melatonin and the inhibitory neurotransmitter GABA – that cause drowsiness and sleep in humans or other animals, had similar reactions in Hydra vulgaris.
According to research, in which a video system was used to see the movement of Hydras vulgaris, it was possible to determine that these animals have an active cycle, similar to that of sleep lasting 4 hours.
Researchers also used vibrations and temperature changes to disrupt hydras' sleep and induce signs of sleep deprivation, causing hydras to sleep more during the next day and even suppressing cell proliferation.
"These experiments provide strong evidence that animals acquired sleep-related mechanisms prior to the evolutionary development of the central nervous system and that many of these mechanisms were preserved as brains evolved," Ito said.