Rather recently, researchers have found that the brain is also reorganizing in adolescence, prompting many to call the adolescent phase a sensitive period of development as well.

The brain areas and networks that are most sensitive to environmental exposure at this time of life are also undergoing rapid reorganization, similar to earlier times in life. As we’ve said, this is the hallmark of a sensitive period.

But what functions are being shaped by the environment in adolescence? They include functions related to social relationships, decision making, especially within peer contexts, and risk taking, as well as functions related to managing stress. This makes sense, when recalling the discussion of the E theme, because brain changes during adolescence involve emotional processing and emotional regulation. These changes can be environment-dependent because not everyone’s environment is the same and each person learns how to manage emotions as a function of its unique experience. In other words, the person who experienced early hardship may operate in ways that differ from those who did not have early adversity.