Final answer:
An imbalance between the brain's cognitive-control and emotional/social networks in early adolescents predicted a rapid rise in alcohol, tobacco, and marijuana use by midadolescence.
Step-by-step explanation:
In a longitudinal study of ethnically diverse early adolescents, a large imbalance between the brain's cognitive-control network and its emotional/social network predicted a rapid rise in alcohol, tobacco, and marijuana use by midadolescence. This relationship underscores the complex interactions between neurodevelopmental processes and the onset of substance use behaviors during adolescence. The evolving neural circuitry, particularly in areas responsible for judgment, impulse control, and decision-making, plays a crucial role. An imbalance in brain networks can lead to increased susceptibility to substance use as adolescents navigate social pressures and emotional changes.