Strategic thinking

How does the brain implement higher-order strategic thinking?

There are many occasions where one does not know what the opponent in a game is going to do. Theoretically, this occurs when the equilibrium involves mixed strategies, or when there are multiple equilibria. To play well in such a situation, one has to go beyond the standard “best response” analysis of Nash and of fictitious play and invoke “thinking about the opponent’s thinking.” Economists such as Colin Camerer would refer to this as “influence analysis” or “higher-order thinking.” Psychologists would recognize this as “Theory of Mind.”

In collaboration with John O’Doherty’s lab at Caltech, we have been able to demonstrate that the neural signals in the quintessential Theory of Mind regions in the human brain reflect the mathematics behind “influence analysis,” and that activation is stronger in humans who are better at it. As such, we have been able to both narrow the scope of Theory of Mind and put Theory of Mind on a solid mathematical foundation. The latter is important because we are now able to measure Theory of Mind in a precise, quantitative way. We published a seminal article on the matter in Proceedings of the National Academy of Sciences.

Our findings are likely to shed light on mental disorders that exhibit deficiencies in social interaction, such as autism spectrum disorder and schizophrenia. As a matter of fact, a group at UCL in London has published work on the relationship between autism spectrum disorder and higher-order strategic thinking.

At the moment, we are collaborating with Alex Fornito and colleagues at the Brain and Mental Health lab at Monash University to study strategic interaction in adolescents and which role it plays in the structure of friendship networks.

Hampton AN, Bossaerts P, O’Doherty JP (2008). Neural correlates of mentalizing-related computations during strategic interactions in humans. Proceedings of the National Academy of Sciences 105(18):6741-6746. article