I think this study is flawed and should have had both groups of men decide how much money to give other men too. Maybe the drug just makes you greedy! Or suspicious of everyone.

I think you're giving him a bit too much credit.

The actual study is up at Why Don't Men Understand Women? Altered Neural Networks for Reading the Language of Male and Female Eyes. (Peeve: an active link purporting to lead to "the study" should lead to the study itself— not an article someone else wrote about the study.)