In a time when college graduates return to live under their parents’ roofs and top careers require years of internships and graduate degrees, the age of adulthood is receding, practically into the 30s. Adolescence, loosely defined as the period between puberty and financial independence, now lasts about 15 years, twice as long as it did in the 1950s.Part of this is due to the declining age of puberty in both males and females, but most of that extension appears in the 20s, when an increasing number of young people are still dependent on their parents. There is some concern that all of this dependence could lead to a lasting immaturity and failure to take on responsibility.But according to developmental researchers, there is one lasting gift that extended adolescence can bestow, and it resides in the brain. “Neurobiological capital” is built through a protracted period of learning capacity in the brain, and it is a privilege that comes to those lucky enough to enjoy intellectually stimulating environments in late adolescence. Far from a contributor to emotional immaturity, the trend toward an adolescence that extends into the mid-20s is an opportunity to create a lifelong brain-based advantage.
Novelty and metaplasticity:
“There is reason to believe that continued exposure to novelty keeps the brain plastic for longer,” says Laurence Steinberg, a psychologist at Temple University whom many consider the leading expert on adolescence. Some of this evidence comes from brain studies of those who have had access to higher education.The window for developing self-regulation closes when adult life settles into a routine, and the brain begins to exchange growth for efficiency. But if an adolescent continues to be stimulated intellectually—through higher education or travel, for example—their brain remains in its formative stage into the mid-20s, and even primes itself for future learning in adulthood. Dubbed “metaplasticity,” changing brain circuits through learning during adolescence can make subsequent modifications easier in those areas.
Adolescence vs. adulthood:
Steinberg likens the distinction between the brain’s adult state and its adolescent development mode to the difference between reading a new book and learning to read in the first place. For an adult to learn, she must pay attention and place information in the context of what she already knows. In contrast, an adolescent brain remembers things even through passive exposure. After that sensitive period has closed, the brain begins to focus on stabilizing the connections it has already made, through the process of myelination. It becomes exponentially more difficult to shape decision-making and higher cognitive functions. Those final pre-adult years may be the last, best chance to put a person on a healthy path.
See my post from Oct. 2014, The Next Level: Universal Children and a New Humanity.