News Humans Moonsleeping bad for spacewalking Day three of the Society for Neuroscience annual meeting offered news about Down syndrome and sleep cycles. By Laura Sanders November 17, 2008 at 4:47 pm - More than 2 years ago Share this:Share Share via email (Opens in new window) Email Share on Facebook (Opens in new window) Facebook Share on Reddit (Opens in new window) Reddit Share on X (Opens in new window) X Print (Opens in new window) Print Day three of the Society for Neuroscience annual meeting offered news about Down syndrome and sleep cycles Melatonin by moonlight Moonlight may interrupt astronauts’ sleep cycles by messing with their melatonin, a new study shows. Sleep cycles are regulated by the type and amount of light that people encounter.