What's the science?

Leadership is critical within our society. Leaders such as teachers, soldiers, politicians and parents, to name a few, are continuously responsible for making decisions that will affect others. One aspect of leadership is the acceptance of responsibility, as leaders are responsible for others in the choices they make. Despite the fact that leadership is central to human societies, we still don’t understand the neurobiology of leadership and why some choose to lead and others chose to follow. This week in Science, Edelson and colleagues use a decision-making task to examine leadership choices and the brain regions involved.

How did they do it?

They developed a behavioural task to examine leadership preferences. The participants performed 2 tasks: a baseline task and a delegation task. In all tasks, the participant’s payoff was dependent on their choices, and therefore assessed preferences related to risk, loss and ambiguity. In the baseline task, they were required to choose whether they would accept a gamble with varying probabilities of loss or gain over several trials. In some trials the exact probability of gains and losses were shown to the participant (to assess risk), while in some trials these probabilities were not shown (i.e. ambiguous and closer to real life decisions). In the delegation task, participants were required to decide on the same gambles, however, they could choose to lead and make a decision on behalf of their group, or defer and follow the choice of the group members. In this task there were two trials, ‘self’ and ‘group’ trials, where the choice of the leader would directly affect the payoff of him or herself or affect the payoff of the group members. The group members as a whole had more information about the probabilities of an outcome, which mimics a real-life scenario where deciding as a group may be advantageous. The authors analyzed baseline choice data to determine whether preferences for risk, loss or ambiguity were associated with leadership scores (obtained using established scales, as well as real life data) and whether there is a shift in these preferences when making choices that impact others. They then used computational modelling and fMRI analysis to understand the preferences for leadership and the brain activity underlying these choices.

What did they find?

In the ‘group’ trials, participants deferred to the decision of the group more often compared to the ‘self’ trials (17.3% increase in deferral rate), demonstrating an overall preference for avoiding responsibility. Responsibility aversion (or avoidance of responsibility) was correlated with leadership scores, where those with lower responsibility aversion had higher leadership scores. Responsibility aversion was not related to individual preferences/ values related to risk, loss and ambiguity, nor was it related to regret, blame, and guilt in social situations (assessed in a separate experiment). They then used a computational model taking into account the participants preferences to try and model these decisions. From participants preferences they were able to derive subjective values (i.e. difference in value between accepting or rejecting a gamble for each participant) of choices to lead or defer. They found that deferral choices were greater when there was a low subjective value difference (i.e. less discriminability between the value of the two choices). In other words, when the participant was more certain of their choice (high discriminability), they were more likely to take on responsibility. They derived ‘deferral thresholds’ whereby a critical level of certainty decides whether they will defer or not in a gamble. Using computational modelling they found that when taking responsibility for others there was a shift in the deferral threshold, indicating a higher demand for certainty of a choice. These changes in deferral threshold were correlated with leadership scores. The greater the shift in the deferral threshold, the more likely an individual was to defer (i.e. not lead). Since individual values about risk, loss and ambiguity were not related to leadership scores, these results suggest that the key to determining whether one will lead or not lies in the shift in the amount of certainty needed (about their decision) now that they are responsible for others.