Considerations of fairness in the adolescent brain - Crone (2013) - Article

Decision interactions have been investigated with various psychological games. These games are aimed at two or more people who exchange goods. This is a conflict where one person wins and the other person loses. This concerns, on the one hand, the own benefits and on the other the benefits of the other.

Already in childhood, there is a sense of 'fair sharing'. In a distribution game, children, adolescents, and adults give away some of their resources to the other because of honesty principles. However, when perspective is taken (thinking from the other person's perspective), adolescents behave more strategically in their social interactions. This indicates that perspective, also known as the Theory of Mind, is not fully developed in childhood but develops into adulthood.

Introduction

Decision interactions have been investigated with various psychological games. These games are aimed at two or more people who exchange goods. This is a conflict where one person wins and the other person loses. This concerns, on the one hand, the own benefits and on the other the benefits of the other.

Already in childhood, there is a sense of 'fair sharing'. In a distribution game, children, adolescents, and adults give away some of their resources to the other because of honesty principles. However, when perspective is taken (thinking from the other person's perspective), adolescents behave more strategically in their social interactions. This indicates that perspective, also known as the Theory of Mind, is not fully developed in childhood but develops into adulthood.

The development of perspective taking

The ultimatum game

In this game, two people must divide a certain amount of money. Person 1 chooses how the money is distributed and person 2 chooses whether he wants to accept the distribution. If this person accepts the distribution, the money is distributed according to this distribution. However, if person 2 does not accept the distribution, both players receive nothing. Adults generally do not accept unfair distributions. Honesty behaviour in this game increases as individuals get older. When children score better on a Theory of Mind task, they are also better in a more strategic game.

A study among different age groups (late childhood to late adolescence) looked at honesty and perspective taking during the ultimatum game. Person 1 was shown two distribution options. There was a condition where person 1 received two unfair options and a condition where person 1 received an honest and an unfair option.

In the condition with an honest and an unfair option, the unfair options were not accepted by most other players. This applied to all ages. In the condition with two unfair options, the unfair option was accepted more often, whereby the older the players, the more often this happened.

A neuroimaging study also looked at this game, where the participants were all in the place of person 2. Previous studies showed that an increased activation was observed in the anterior insula, the anterior cingulate cortex and the dorsolateral prefrontal cortex, related to waling, negative affect, conflict and control.

In another study, the dorsolateral prefrontal cortex and temporoparietal junction in adults were more active in the unfair distribution when only an unfair distribution was possible. These areas of the brain have to do with the suppression of selfish responses and perspective taking.

Comparison of adolescent participants in different age categories showed that the above activity in the dorsolateral prefrontal cortex and the temporoparietal junction was positively related to age.

The game of trust

In the game of trust, two people divide a sum of money. Person 1 may choose to share a certain amount with the other player or to have the other player divide the amount. When person 1 chooses the latter, the amount is tripled. Person 2 can then choose to divide the tripled amount fairly, or to keep most of it.

Research was conducted among persons in late childhood to late adolescence, with the participants all taking the place of person 2. The risk for person 1 was varied. The degree of general reciprocity increased between nine and sixteen years. After this the pattern became stable. At high risk for person 1, reciprocity increased with age.

A neuroimaging study was also conducted among adolescents and young adults. Here too, all participants were given the position of person 2. When the participant gained the confidence of person 1, there was increased activation in the dorsolateral prefrontal cortex and the temporoparietal junction. This increased with age.

The self-centeredness of the young adolescent

Young adolescents become better at taking a perspective through greater self-orientation. The trust game looked at brain activation of person 2, in reciprocity and when keeping the amount yourself. For all participants, there was increased activity in the dorsomedial prefrontal cortex in keeping the money themselves. However, in young adolescents, there was also increased activity in this brain structure in reciprocity. This brain structure is also more active in this group in thinking about themselves and in shame.

The importance of past interactions for honesty

There is a strong urge to 'belong' in adolescence. Therefore, there may be an influence of previous interactions with peers and honesty considerations.

Social rejection is associated with increased activation in the anterior cingulate cortex and the insula. This activation is comparable in adolescents and adults. Adolescents also have increased activation in the subgenital cingulate cortex, related to negative affect.

When adolescents played the dictator game with players who had previously excluded them, punitive behaviour was observed, especially among young adolescents (the other players were allocated less money). There was increased activity in the ventrolateral prefrontal cortex, the temporoparietal junction, the anterior cingulate cortex and the insula.

Conclusion

The activity in the dorsolateral prefrontal cortex and the temporoparietal junction when thinking of the intentions of the other increases with age. In early adolescence, there is increased activity in the dorsomedial prefrontal cortex. This structure is linked to self-directed thinking.

The activation of the dorsolateral prefrontal cortex is associated with the inhibition of egoism.

The different brain areas mentioned above develop in activity during the adolescence period. The activity of impulse control (dorsolateral prefrontal cortex) and perspective taking (temporal parietal junction), increases greatly during early adolescence, stabilizes in mid-adolescence and decreases slightly in late adolescence. The activity of 'self-focus' (MPFC) decreases enormously during adolescence.

These brain regions also interact with other brain regions and are therefore not isolated.

The process of making decisions in adolescence changes from self-directed processing to other-oriented processing.