Teenagers’ Poor Decision-Making Linked to Brain Development, Study Shows
Adolescents are often criticized for making impulsive or erratic decisions, but a new study published in PLOS Biology sheds light on the underlying causes. Researchers from the University of Würzburg, Germany, have identified a key link between teenagers’ “noisy decisions” — choices marked by inconsistency and randomness — and ongoing brain development. Their findings reveal that as the brain matures, decision-making becomes less noisy, more consistent, and increasingly strategic, helping individuals adapt better to complex situations in adulthood.
The Study Behind the Findings
The research was spearheaded by neuroscientists Vanessa Scholz and Lorenz Deserno at the University of Würzburg, and its findings were published in November 2024, in the esteemed open-access journal PLOS Biology. The study builds upon previous research into adolescent behavior but takes a unique approach by examining how “noisy decisions” — marked by inconsistency and randomness — evolve as the brain matures. This novel perspective highlights how variability in decision-making, known as decision noise, influences the development of more strategic and adaptive behaviors in adulthood.
The study involved 93 participants aged 12 to 42 years, providing a broad spectrum to capture changes in decision-making across adolescence, young adulthood, and mature adulthood. This wide age range allowed researchers to observe how decision noise, as well as other cognitive behaviors, evolved over time. According to Neuroscience News, the research aimed to uncover the mechanisms linking these developmental changes to improvements in decision-making strategies, such as planning and goal orientation.
To evaluate decision-making processes, participants were tasked with completing three distinct reinforcement learning tasks, each designed to capture a specific aspect of decision-making:
- Motivational Influences on Choices: This task examined how rewards influenced participants’ decisions. By analyzing the extent to which choices were driven by external incentives, researchers could assess how motivation shapes decision-making strategies across age groups. For example, younger participants often displayed stronger responses to immediate rewards, indicating heightened sensitivity to external stimuli, whereas older individuals exhibited more balanced responses.
- Adaptive Decision-Making: In this task, participants were required to adjust their decisions in response to dynamic changes in their environment. This component measured cognitive shifting, a critical skill for navigating complex and evolving scenarios. Younger participants demonstrated higher variability, suggesting a struggle to adapt to new patterns, while adults showed more consistent adjustments.
- Goal-Directed Behavior: The final task tested participants’ ability to make deliberate, long-term decisions with a clear objective in mind. Adolescents often struggled with strategic thinking and displayed more impulsive choices, while adults demonstrated stronger goal-oriented behaviors and the ability to prioritize effectively.
Computational Models and Analysis
To quantify decision noise, the researchers employed computational modeling techniques that assessed the variability or randomness in participants’ choices. These models provided a nuanced understanding of how decision-making evolves at a computational level. Decision noise was found to decrease significantly with age, aligning with the maturation of brain areas involved in cognitive control, such as the prefrontal cortex.
The study also uncovered correlations between reductions in decision noise and improvements in strategic behaviors, such as planning and adaptability. These findings suggest that decreasing noise plays a pivotal role in fostering more efficient and goal-oriented decision-making processes.
Novel Contributions to the Field
While prior research into adolescent decision-making has largely focused on factors such as impulsivity or emotional regulation, this study introduces a groundbreaking perspective by identifying decision noise as a key mediator of cognitive development. It bridges the gap between general developmental changes in brain function and specific improvements in decision-making.
Moreover, the study highlights the role of reinforcement learning — a cognitive process by which individuals learn from feedback — in shaping age-related improvements in adaptability and planning. By focusing on how variability in choices evolves over time, the research emphasizes the importance of understanding decision noise as both a challenge and an opportunity in cognitive development.
Key Findings of the Study
- Teenagers Show Higher Levels of Erratic Decision-Making. Adolescents were significantly more likely to make inconsistent, chaotic choices across all tasks in the study. This high level of erratic decision-making highlights their reliance on underdeveloped cognitive processes and simpler strategies, which often lead to unpredictable outcomes.
- Erratic Decisions Decrease With Age. As participants aged, their decisions became less chaotic and more deliberate. This finding reflects the gradual maturation of the prefrontal cortex and other brain regions involved in cognitive control, enabling better focus, planning, and consistency in choices.
- Better Planning and Goal-Oriented Behavior in Adults. Older participants performed better in tasks that required long-term planning and goal-directed behavior. As erratic decision-making decreased, their ability to weigh options, prioritize goals, and execute strategic plans improved, showcasing a direct link between cognitive maturation and enhanced decision-making.
- Improved Adaptability With Age. Adults demonstrated superior adaptability in tasks that required adjusting decisions to environmental changes. This flexibility is crucial for navigating complex, dynamic situations, and reflects the development of advanced problem-solving skills as chaotic decision-making declines.
- Brain Development as a Key Factor. The findings highlight the role of brain maturation—particularly in the prefrontal cortex—in reducing chaotic decision-making. These neural changes allow for better integration of information, improved cognitive control, and more consistent, purposeful behavior.
- Teenagers Are More Prone to Emotional and Social Influences. High levels of erratic decision-making made adolescents particularly susceptible to emotional rewards, peer pressure, and impulsive choices. This finding underscores the importance of external influences during adolescence and their role in shaping decision quality.
Why Does This Matter?
Scientific Significance:
- This study deepens our understanding of the neurobiological basis of decision-making, linking chaotic decision-making to brain development.
- It identifies measurable factors that help explain how cognitive maturation impacts behavior and adaptability.
Medical Applications:
- Adolescents with neurodevelopmental disorders like ADHD or autism may exhibit persistently chaotic decision-making.
- These findings could guide early interventions to improve cognitive skills and emotional regulation.
Educational and Parenting Insights
- Structured environments, clear guidance, and emotional support are crucial for helping teenagers develop better decision-making skills.
- Teaching practical strategies can accelerate cognitive growth and improve decision-making consistency.
Societal Implications:
- These findings promote protecting teenagers from harmful pressures and fostering environments that support healthy development.
- Understanding adolescents’ susceptibility to external influences is essential for developing ethical policies in education, mental health, and advertising.
The findings have significant implications for understanding adolescent behavior in everyday contexts. For instance, high levels of decision noise in teenagers may explain their tendency toward impulsive or inconsistent choices, such as switching between goals or struggling with prioritization. In contrast, the gradual reduction of noise with age reflects the brain’s increasing ability to support deliberate, purposeful decision-making.
Additionally, the study underscores the importance of educational and therapeutic interventions that target decision-making skills. Structured activities designed to reduce decision noise — such as problem-solving exercises or tasks that simulate real-world decision-making scenarios — could help adolescents develop more consistent and adaptive behaviors.
Conclusion: From Impulsivity to Strategic Thinking
This study sheds light on why adolescents struggle with decision-making and how their brains develop to support better choices over time. As chaotic decisions decrease with age, individuals become more consistent, strategic, and adaptable—critical skills for navigating adulthood.
Cognitive training can play a pivotal role in accelerating this developmental process. Exercises that target attention control, strategic planning, and problem-solving not only strengthen the underlying cognitive abilities but also provide teenagers with tools to manage decision-making challenges more effectively. Techniques such as mindfulness meditation, memory-enhancing activities, and scenario-based problem-solving tasks can help adolescents refine their thought processes and reduce impulsivity.
Implementing such training in schools, extracurricular programs, or even family settings could make a significant difference. For example, gamified apps that simulate real-life decision-making scenarios or structured classroom activities focused on planning and prioritization can create engaging ways for teenagers to practice critical thinking skills. Parents and educators can also encourage decision-making by allowing teenagers to participate in structured choices with clear feedback, fostering a sense of responsibility and confidence.
Cognitive training is not just about reducing chaos in decisions—it also prepares adolescents to handle complex, real-world situations. By reinforcing adaptability, logical reasoning, and goal-oriented behaviors, these interventions equip young people with lifelong skills for personal and professional success.
Ultimately, the research highlights that erratic or suboptimal decisions are not flaws but natural steps in the growth process. With time, brain maturation, and deliberate practice through cognitive training, teenagers evolve from impulsive decision-making to thoughtful, deliberate choices that align with long-term goals and societal expectations.
