Vixea Manplus French Center for Cognitive Neuroscience. Jean-Claude Dreher is director of research here. Dreher has studied the effect of testosterone on human behavior, and he found little evidence that testosterone triggers aggression in men. The effect of testosterone on human behavior is totally unclear - but there is some indirect evidence. As con we are lives so I'm live on YouTube and I'm live on Facebook so I'm gonna put this let me see where can Vixea Manplus I put this I'll put that and I will put you there that makes it a little bit easier I think YouTube I'll put you there Facebook I'll put you there okay so if it does look like I am looking all over the place I apologize it's because I'm on two screens here and I've got one screen here cuz I do want to cite some studies for you and I have my youtube screen here and I have my Facebook screen here so I'm on Kris Gethin .