Motivation

For several weeks we have discussed various aspects of the Ultimatum and Investors game. This week’s readings expand on these studies.

I think that studies such as those by Sanfey (2003) and Kosfeld and Fehr (2005) do not answer one of the most important questions: how does absolute wealth in a one-off game change empathic responses or one’s perception of trustworthiness? From an evolutionary standpoint, the marginal utility that the responder gets from each additional dollar varies depending on whether the responder is Bill Gates or a person below the poverty line. Increases in activity in areas associated with emotion and cognition should be able to be explained on the basis of Darwin’s concepts of fitness and/or survival.

We might thus expect one who is less in need of the money from the ultimatum game to elicit not as elevated activity levels in the anterior insula and dorsolateral prefrontal cortex after an unfair offer. In comparison, a responder who is starving, and needs at least a 30% offer to buy his next meal will likely experience increased activity levels, at least in the anterior insula (emotion).

Kosfeld can similarly expand his studies. Would you expect the effect of oxytocin to be less powerful depending on whether the investor were handing over 1% of his net worth as opposed to 99% of his net worth? I certainly would.