Discovery Channel
In the 1980s, young entertainers sang and talked of the feelings and frustrations of the teen years. Most teenagers were familiar with the feelings of wanting things they couldn't have and being under the control of adults who didn't understand them. More recent studies have shown that changes in hormones and appearance aren't the only things going on during the teen years.
Scientists once thought that brain growth was complete and patterns were set by the age of 3 years. Magnetic resonance imaging, or MRI, has shown that the brain also goes through a teen growth spurt. But just as a developing teenage boy's voice changes up and down, teens' brains grow a little unevenly. Some of the connection between different neural regions improves, but many parts of the brain still aren't mature. This may explain why some teens drift toward risk-taking, impulsivity and other behaviors that parents find hard to understand.
During the teenage years, the brain experiences a burst of growth of synapses, or connections. Compared with the adult brain -- in which the different parts work together -- a teenage brain is more like your entertainment center when it first arrives and the components are not connected. The part of the brain that ties things together and helps control impulses and emotions is the prefrontal cortex -- this is also the part of the brain most involved in making judgment calls about situations and in understanding the relationship between the self and other people. Scientists have found that it is less mature in a teen brain than in an adult one, which may be a major reason that teenagers can make poor decisions and often feel misunderstood or out of place.
One area of teen brains develops early -- the nucleus accumbens. This center is associated with pleasure and reward. The teen nucleus accumbens is not balanced by a mature prefrontal cortex, so teens also handle reward, impulses and consequences differently than adults.
Link:
http://curiosity.discovery.com/question/reason-teenagers-feel-misunderstood
This website comes from Discovery.com, and talks about the reasons teenagers feel misunderstood. This site contains the above, and a short video near the bottom of the website page, that explains the above through visuals.