Final answer:
The lack of maturity in the brain's frontal lobes, responsible for planning and impulse control, is due to the ongoing development into early adulthood. The prefrontal cortex matures throughout adolescence, explaining increased risk-taking and emotional outbursts. Significant growth during childhood and the elementary years is key for developing impulse control.
Step-by-step explanation:
The reason for the lack of maturity in the brain's frontal lobes, which are associated with planning and impulse control, is due to the ongoing development that continues into early adulthood. During adolescence, significant changes occur in the prefrontal cortex (PFC), part of the frontal lobes. The PFC is crucial for executive functions, such as decision-making, abstract reasoning, evaluating risks and rewards, and controlling impulses. These functions mature over time as the brain develops, which is why adolescents may exhibit increased risk-taking behaviors and emotional outbursts. The frontal lobes grow rapidly during early childhood, and significant brain growth continues through the elementary school years, which is essential for the advancement of cognitive abilities, including impulse control. Furthermore, episodes like the case of Phineas Gage, who suffered damage to his frontal lobes, demonstrate the important roles these brain areas play in personality and social behavior, as well as in regulating emotional impulses.