An adaptive role of collective decisions: shared responsibility in the human brain

People often prefer to make decisions in a group, although many of these decisions do not lead to better choices when compared with decisions made as an individual.

I propose that the function of joint decisions is not to improve the outcomes of decisions. Instead, people cooperate to share the responsibility for their actions with others, thereby protecting themselves from any possible punishment. This implies that a person should feel less responsible for collective actions and choose to cooperate  when there is the possibility of punishment. It follows that individuals would be more severely punished as compared to a group. By experimentally testing these predictions at the behavioral and brain levels in human participants, this work will clarify the usefulness of cooperative behaviour.

The findings of this project have important implications for issues related to norm-enforcement in society and judicial impartiality.