Here is my hypothesis why human's sleep pattern and brain activity changes and apperently peaks at full moon.
It's probably the electro magnetic field of the moon itself that influences earth's electro magnetic field and this subsequently influences the operat ion of the human brain which also communicates via electrons which are know n to be influenced by all kinds of electro magnetic fields.
(The moon wobbles a bit, not sure if the moon is closer when it's full moon , full moon might have nothing to do with it, then again it does, another h ypothesis could be the increased photons reflecting from the moon onto eart h is also changing electro magnetic field, and finally carbon is also emitt ed from the moon and might also hit earth's field and maybe change it too : P)
(Perhaps the moon even influences electronics, heck if it's strong enough t o pull vast quantities of water in ebs and ties then who knows ! ;) :) LOL)
Bye, Skybuck.