Mind-Brain Lecture: Giorgio Coricelli (CNRS Lyon)
Hosted by Hauke R. Heekeren
We used fMRI to measure the neural correlates of strategic uncertainty in
games and lotteries. Participants played a series of stug hunt games,
entry games, and lotteries. The two games differ in their equilibrium
properties: stug hunt games are games of strategic complementarity (e.g.,
an investment pays off if and only if a sufficient number of agents invest
in the same industry, so all invest and nobody invest are two Nash
equilibria) while entry games are of strategic substitutability (e.g., if
too many agents invest in a new market all get nothing; here we should not
all do the same, but instead choose mixing strategies in equilibrium). A
mentalizing network (mPFC, TPJ, STS, precuneus) is activated in games
playing vs. Lotteries, thus distinguishing the social and the private
nature of the choice context. Furthermore, we found a behavioral
correlation and a similar pattern of activity in the striatum between
choosing lotteries and choosing the stug hunt game; while insula and
lateral OFC activity was mainly related to entry games choices.
Interestingly, we found a clear separation of insula activity in lotteries
and stug hunt games when distinguishing between risk averse and risk
loving players. However, in entry games this distinction is not at all
found. We conclude that the entry game creates more strategic uncertainty
as predicted by the nature of the theoretical equilibrium which also
involves levels of reasoning. While the strategic uncertainty of the stug
hunt game can be 'reduced' to standard risk, the uncertainty underlying
entry games is higher and analogous to ambiguous choices.
Dr Giorgio Coricelli, Centre de Neurosciences Cognitives, Institut des Sciences Cognitives , http://www.isc.cnrs.fr/sir/CVCoricelli2007.pdf
All are welcome!
