By age 16, 70% of teenagers are capable of sequential logical
thinking, considered to be an adult stage of thought.1
They develop the ability to think abstractly, deal with several concepts at the
same time, and imagine the future consequences of their actions.
These teens are now able to process more complex problems, to develop
and test theories, to understand analogies, to reason inductively and
deductively, and to think inferentially. They are better able to handle the
rigors of a more demanding high school curriculum because their memory and
organizational abilities—such as time management, test preparation, and study
skills—improve. Written and spoken language become increasingly more
sophisticated. They may be able to grasp political, moral, social, and
philosophical concepts.
In some cases teens grow a bit arrogant with these newfound mental
abilities, and parents often complain that their teens "know everything." It
can sometimes be difficult to deal with teens during this time because although
they understand that others have differing viewpoints, they often firmly
believe their own perception is the most true or valid.
Even though teens develop adult cognitive abilities, they still do
not have the life experiences to guide them in making the best choices. Indeed,
adults struggle with this, too. They may reason that focusing on getting good
grades in high school may further their academic future, but they might choose
to spend their time working or socializing.
Researchers theorize that a teen's experiences determine, to a large
degree, which connections in the brain are made stronger and which are
"pruned," a sort of "use it or lose it" process. Researchers suggest that
teens' accomplishments in sports or academics, for example, may positively
affect the way they think for the rest of their lives. Advanced mental
development may be the result of dramatic brain growth during puberty and then
a refining process seen in the late teen years.