Summary: It’s a common trope that teenagers can be self-centered, but new research provides a computational look at why. A study reveals that while adolescents are just as good as adults at noticing when someone is being kind, they are significantly less likely to return the favor.
Using the “Prisoner’s Dilemma” game, researchers found that teens often prioritize their own immediate interests even when their partners consistently cooperate, suggesting that the “reward of reciprocity” hasn’t yet fully developed in the adolescent brain.
Key Facts
- The Reciprocity Glitch: Teens and adults were equally accurate at estimating how cooperative their partners were. The difference wasn’t in perception, but in action—teens noticed the kindness but felt less motivated to mirror it.
- Selective Cooperation: Adolescents were just as quick as adults to stop cooperating if a partner “betrayed” them. However, they failed to increase their cooperation when a partner remained consistently helpful.
- Computational Insights: Using mathematical models, researchers found that the “reward value” of cooperating with others is much lower for 14–17-year-olds than for 18–30-year-olds.
- Self-Interest Peak: Adolescents focused more on personal gain during social dilemmas, even when a win-win scenario was clearly available through mutual work.
Source: eLife
Researchers have found that adolescents focus more on their own interests compared to adults when navigating social dilemmas, even when their interaction partners show greater willingness to cooperate.
The study, published today in its final Version of Record after appearing previously as a Reviewed Preprint, supports previous findings that teens tend to cooperate less than adults, and sheds new light on how our willingness to work with others changes from youth into adulthood.
eLife’s editors describe it as important work, with a solid experimental approach to investigate cooperative behaviours in adolescents.
In everyday life, people often need to choose between acting in a way that serves their own interests and cooperating with others. While cooperation can help build positive relationships and reach shared goals, it can also mean giving up some immediate personal gain.
“Adolescence is a time when young people learn how to navigate friendships and work with others in groups, but research suggests they remain less cooperative at this stage of life. We wanted to build on those findings to understand why this is the case,” says Xiaoyan Wu, who completed her PhD at State Key Laboratory of Cognitive Neuroscience and Learning, and IDG/McGovern Institute for Brain Research, Beijing Normal University, China, and is now a postdoctoral researcher at the University of Zurich, Switzerland.
Wu is a co-first author of the study alongside Hongyu Fu, a doctorate student at State Key Laboratory of Cognitive Neuroscience and Learning, and IDG/McGovern Institute for Brain Research.
The team recruited 261 participants to the study: 127 adolescents aged 14–17 years and 134 adults aged 18–30 years. They used a repeated cooperation game called the Prisoner’s Dilemma Game, where each participant was partnered up and placed in a situation where they could either work together for a shared benefit, or try to gain more for themselves at their partner’s expense.
The researchers used this approach to see whether the younger participants failed to notice when a partner behaved kindly and in a cooperative manner, or whether they noticed it but were more tempted than adults to take advantage of the situation and gain more for themselves.
They saw, first of all, that teens cooperated less than adults, in line with the previous findings. This lower level of cooperation was not observed generally during the task, but occurred especially after their adult partners had cooperated in previous rounds.
They also found that teens and adults were similarly good at estimating how cooperative the other person was – suggesting that adolescents notice when others are willing to work together, but feel less motivated to reciprocate.
The researchers also developed computational models to investigate the dynamic variables guiding participants’ cooperative decision making in the repeated Prisoner’s Dilemma Game. They incorporated both the participants’ expectations of their partner’s cooperation and the reward of reciprocity.
Their models revealed that adults cooperated more in response to their partner’s consistent cooperation, while this pattern was absent in adolescents. However, both groups decreased cooperation in response to their partner’s consistent defection, indicating shared responses to non-cooperative behaviour.
“Our findings contribute to an understanding of the developmental aspects of cooperation and the cognitive-affective processes underlying cooperative decision making,” says co-first author Hongyu Fu.
“By comparing the cooperative behaviours between adolescents and adults during the game and integrating computational modelling, we share valuable insights into the mechanisms driving cooperative behaviour across different developmental stages.”
The researchers note that there are some limitations to their work. For example, their study involved using artificial opponents with pre-determined cooperation patterns, while it is possible that participants might behave differently in more natural scenarios.
Additionally, although participants were recruited from Beijing and nearby regions, minimising regional and cultural variations, they may still differ in their socioeconomic status and social experience. These differences could interact with developmental processes in shaping their cooperative behaviours.
Taking these limitations into account, the authors say their work provides an initial step in understanding cooperation motivations, with the potential for future research to explore these behaviours in more real-world contexts.
“Increasing our understanding of these behaviours could have implications for designing effective interventions to better support teenagers’ social development,” concludes senior author Chao Liu, Professor at State Key Laboratory of Cognitive Neuroscience and Learning, and IDG/McGovern Institute for Brain Research.
“Our results suggest that it may help to teach teens to understand others’ intentions, as well as to strengthen how much they value fairness and reciprocate when others are kind and cooperative. It will be interesting for future studies to test whether the patterns we’ve observed also appear in more realistic situations and in more diverse groups of young people.”
Key Questions Answered:
A: Not at all. The study found that teens are actually quite sharp at reading social cues. They knew exactly how cooperative their partners were being. The “disconnect” happens in the decision-making phase; they recognize the olive branch but choose to keep the extra “reward” for themselves anyway.
A: It’s less about malice and more about brain development. Adolescence is a transition period where the brain is still learning to value long-term social harmony over immediate personal gain. They have the “defensive” side of cooperation down (quitting when someone is mean), but the “proactive” side (being nice back) takes more time to mature.
A: Senior author Chao Liu suggests that interventions should focus on two areas: helping teens better understand others’ intentions and specifically strengthening how much they value fairness. It’s not enough for them to see the kindness; they need to be taught why reciprocating that kindness is valuable in the long run.
Editorial Notes:
- This article was edited by a Neuroscience News editor.
- Journal paper reviewed in full.
- Additional context added by our staff.
About this social neuroscience research news
Author: Emily Packer
Source: eLife
Contact: Emily Packer – eLife
Image: The image is credited to Neuroscience News
Original Research: Open access.
“The self-interest of adolescents overrules cooperation in social dilemmas” by Xiaoyan Wu, Hongyu Fu, Gökhan Aydogan, Chunliang Feng, Shaozheng Qin, Yi Zeng, and Chao Liu. eLife
DOI:10.7554/eLife.106840.4
Abstract
The self-interest of adolescents overrules cooperation in social dilemmas
Cooperation is essential for success in society. Research consistently showed that adolescents are less cooperative than adults, which is often attributed to underdeveloped mentalizing that limits their expectations of others.
However, the internal computations underlying this reduced cooperation remain largely unexplored.
This study compared cooperation between adolescents and adults using a repeated Prisoner’s Dilemma Game. Adolescents cooperated less than adults, particularly after their partner’s cooperation.
Computational modeling revealed that adults increased their intrinsic reward for reciprocating when their partner continued cooperating, a pattern absent in adolescents.
Both computational modeling and self-reported ratings showed that adolescents did not differ from adults in building expectations of their partner’s cooperation.
Therefore, the reduced cooperation appears driven by a lower intrinsic reward for reciprocity, reflecting a stronger motive to prioritize self-interest, rather than a deficiency in predicting others’ cooperation in social learning.
These findings provide insights into the developmental trajectory of cooperation from adolescence to adulthood.
