Getting infected by a parasite doesn’t sound like a sure fire way to get over your fears, but it totally works -- at least in mice. A bizarre parasite called Toxoplasma Gondii actually makes mice unafraid of cats -- once they are infected with it -- by taking over a part of their brains. Scientists aren’t sure exactly why this happens, but get this: The change seems to be permanent. I guess we know who will put the bell on the cat now, don't we??