In particular , low levels of melatonin may stop the depolarization current in the nerves , preventing the stimulation of the muscles and any consequent enactment of the dream activity by the body -LRB- e.g. preventing a sleeper from flailing his legs when dreaming about running -RRB- .

In particular , low levels of melatonin may stop the depolarization current in the nerves , which prevents the stimulation of the muscles .
