Severed alligator head & dog head transplant

The Alligator head is moving for quite a long time i think!I dont know how long chickens can run without their heads or if its possible that the story about Stoertebeker is really true (According the legend he past 11 men of his crew after his head was severed )...  I tried to find out something about whats happening in the heads, but there are only some storys about brain reflexes . I wish there was  more information about this stuff because i have a lot of questions in my mind. Also there is this video