Why do eyes move in sleep?

Scientists from the University of Freiburg have discovered a nucleus (a collection of neurons) that selectively triggers rapid eye movements during REM sleep. As it turned out, it is located in the medulla oblongata and has projections (“pulls” its axons) into the nuclei of the oculomotor nerves. An article in the journal Nature Communications is devoted to a description of the features of its work and how exactly it controls paradoxical sleep.