Most people have an idea of what is fair and unfair in a typical situation…

Well, according to a new study, the ability for teenagers to consider the intentions of others when it comes to fairness is linked to structural changes within brain.

The study involved individuals between age 9 through 23. The participants played an “ultimatum game” that involved money. The game consisted of dividing $10 into two different amounts. After the division was made, the other participant had to choose whether to reject the amount offered to them, or to accept the division. As this was occurring, the researchers investigated the participants decision making skills, and measured the amount of cortical thickness through a magnetic resonance imaging (MRI).

The results showed the younger participants tended to divide the money evenly, while older adolescents were more meticulous when considering the opposing player’s intentions. This more “sophisticated strategy that considers both the other player’s intentions and notions of reciprocity” seen in older players showed a change in their brain structure; these individuals were found to have cortical thinning in the brain within the prefrontal cortex, and the temporal cortex, which determines how we view others, and how we process their expressions.

“We were surprised that this shift in preference for considering others’ intentions occurred so late in development. Of course, younger children can infer the intentions of others, but we see that this ability continues to be refined well into late adolescence…this finding has potential implications regarding how much autonomy this age group should be given when making important social and ethical decisions, such as purchasing weapons, going to war, and serving on juries…” stated Luke Chang, an assistant professor in the Department of Psychological and Brain Sciences and the director of the Computational Social Affective Neuroscience Laboratory at Dartmouth University.