The thing about the teenage brain is that it is not a finished product. Although if you ask any teenager, they feel like they can do anything just as good as any adult can. But the fact is, cognitively, their brains are still immature. There are several key differences between the adult and the teen brain, and one of them has to do with how it develops. First of all, it does not develop all at once; it grows back to front, unevenly. Thus, the last part to develop is the prefrontal cortex, which is the “control center” for reasoning and impulses. This part of the brain takes a very long time to develop and is not fully mature until around 25 years of age. This explains why teenagers may suffer difficulty controlling emotions, poor planning, and impulsive behavior.