First I came across a lecture he gave for Class Day 2009 at Stanford on the Uniqueness of Humans. Don't let the idea that he spoke at Stanford put you off of watching. It's aimed at a general audience and well worth it.
Then I went looking for some other videos and came across a couple where he discusses some ideas on where religion may have come from. My university lecturers weren't anywhere near as interesting. Professor Sapolsky Explains the Origins of Religion part 1, and part 2.
But back to the topic of today's symposium... here's an interview from Edge.org where he talks about the Toxoplasma parasite in rats and then in humans. (with detours to a few other areas of research). It turns out that Toxo does affect us humans. It may not be as specifically directed an effect as the one found in rats. Mammalian chemistry is similar enough so there are changes to the brains of humans who are infected.
I wonder what other parasites and diseases also alter our behaviour? There may be more than we think. To quote from the beginning of the interview:
In the endless sort of struggle that neurobiologists have — in terms of free will, determinism — my feeling has always been that there's not a whole lot of free will out there, and if there is, it's in the least interesting places and getting more sparse all the time. But there's a whole new realm of neuroscience which I've been thinking about, which I'm starting to do research on, that throws in another element of things going on below the surface affecting our behavior. And it's got to do with this utterly bizarre world of parasites manipulating our behavior.Bizarre indeed. I may have to have a chat with my three cats. Who knows what else they are carrying around.