Final answer:
The true statement regarding brain changes during adolescence is that synaptic pruning occurs, which eliminates unused neuronal pathways and improves brain efficiency. Myelination also increases, and neurogenesis continues into adulthood, both of which are pivotal for learning and memory formation.
Step-by-step explanation:
The true statement about changes in the brain during adolescence is that synaptic pruning occurs. During adolescence, the brain doesn't significantly increase in size but instead becomes more complex. The process of synaptic pruning involves the elimination of unused neuronal pathways, making the brain more efficient. Concurrently, myelination increases, leading to improved brain functionality. Contrary to a decrease in neuronal connections, they are reorganized, and this dendritic plasticity plays a crucial role in memory formation and learning. Furthermore, the frontal lobes continue to develop well into a person's mid-twenties, and neurogenesis, the birth of new neurons, persists into adulthood, which has implications for learning and adaptation to new experiences.