The researchers played a sound and then, after a set period of time that varied between each group, blew a puff of air into the rats' eyes, making them blink.
One churchman was confronted with a village of people who genuinely believed the claims of a woman who claimed to be a witch and who said, amongst other things, that she could turn herself into a puff of smoke and leave a locked room through the keyhole.
But Vatican insiders aren't the only prospective pontiffs punters can wager on in the hopes that a puff of white smoke will finally put their bank accounts into the black.