A recent study by Penn Medicine provides new insights into human brain development, showing that the brain does not develop uniformly but follows a newly identified developmental sequence. This study, which used magnetic resonance imaging (MRI) to study the brains of individuals aged 8 to 23 years, reveals that brain regions involved in cognitive, social, and emotional functions appear to remain more malleable (capable of changing and adapting) for a longer period than other brain regions, making adolescents more sensitive to their socioeconomic environment.

Brain plasticity refers to the ability of neural circuits — the connections and pathways in the brain related to thought, movement, and emotions — to change or reorganize in response to internal biological signals or external influences. While it is generally understood that children have higher brain plasticity than adults, this study provides new insights into where and when reductions in plasticity occur during childhood and adolescence.

The findings show that reductions in brain plasticity occur first in sensory-motor regions, such as the visual and auditory areas, and occur later in associative regions, involved in higher-order thinking such as problem-solving and social learning. These later-developing regions, which are vital for cognitive development, social interactions, and emotional well-being, appear to be particularly malleable and responsive to the environment during early adolescence, as plasticity occurs later in development.

This study marks a significant advancement in understanding how the brain adapts and changes throughout adolescence. The researchers also found that socioeconomic environments can have a larger impact on late-maturing associative brain regions, suggesting that a young person’s social and economic environment plays a major role in shaping their brain development through adolescence.

This work provides a solid foundation for understanding how the environment shapes neurodevelopmental trajectories in adolescents and emphasizes the importance of educational and enrichment programs that address disparities in youths’ socioeconomic environments, fostering positive brain development.