The idea of the faulty teen brain has been fashionable since the turn of the 19th/20th century when the early stages of the Industrial Revolution eliminated what was left of the rights that young people used to enjoy, and the mid-19th century Victorian concept of the "innocent youth" was extended to include anyone under the age of 18.

As a result of this, the concept of a distinct phase of life that came to be called "adolescence" entered the official public consciousness in a major way, and this concept was mostly pioneered by the beginning of the 20th century courtesy of the social conservative psychologist and author G. Stanley Hall. Hall used aspects of what we today call Social Darwinism and misuse of evolutionary biology to claim that the life stage of adolescence was a natural biological reality rather than a social construct. He diligently opposed what he referred to as "precocity" in young people, which can easily be translated as, "Do not let young people do anything more than what society believes they should be doing at that current age, and society should insure that young people at this newly conceptualized stage of life universally adhere to the socio-cultural paradigm we have established for their age group."

As Hall biographer Nancy Lesko said in this article:
education.stateuniversity com/pages/2026/Hall-G-Stanley-1844-1924.html,

"The shapers of the modern, scientific adolescent made growing bodies and sexuality primary foci and the measures to prevent precocity enhanced youth's economic dependence". Sociologists and psychologists who have studied the concept of adolescence have increasingly come to question Hall's biological conception of adolescence as being a distinct and natural phase in human development that marks a period between childhood and full adulthood that requires individuals in this intermediate stage to have the same degree of legal and social controls as it came to be believed that children should have since the Victorian era began. This new social construct resulted in young people under the age of 18 who fit into this new category to be given the same legal and social status that pre-pubescents ended up with during the Victorian period (indeed, Western culture tends to view adolescents under 18 as older children rather than young adults). Hall's increasing number of opponents in the social sciences over the course of time began to view his conclusions as outdated.

Major and notable challenges to Hall's theory on adolescence include French sociologist Philippe Aries' book Centuries of Childhood (published in the French speaking world in 1960 and first translated into English in 1962). This tome ended up having a major impact on the social sciences during the liberal era of the 1970s when progressives of that decade began to reassess society's attitude towards younger people that was largely established by Hall and his Victorian predecessors. These reconsiderations of the status of youth included questions regarding their subservient role in the present day social institutions (such as within the nuclear family unit and within the modern elementary and secondary school systems). This was a truly progressive idea that was sadly derailed when the onset of the sex abuse hysteria and the conservative takeover of government, beginning with Ronald Reagan's presidential election in 1980, rolled back the emerging youth liberation movement of the '70s (begun notably in Ann Arbor, Michigan). Further, the combination of the sex abuse hysteria and the conservative takeover of government (which complimented each other heavily) cowered most of the liberal elements of society who began considering the validity of youth competence (including their sexual rights) in the '70s into silence and outright capitulation to the demands of the newly empowered social conservatives. This was motivated by these progressives' fears of being called "anti-family," "insensitive to victims of child abuse," and other highly unpleasant, potentially career-destroying epithets.

And so things remained until the Internet bloomed to the level we recognize it as today in the late 1990s when the youth liberation movement was reborn in a significant way with the establishment of ASFAR (Americans for a Society Free from Age Restrictions) and, later, the even bigger and more influential youth lib org NYRA (National Youth Rights Association; created by somewhat less radical individuals who had left ASFAR).

All of this led to the pioneering efforts of more scholars in the social sciences such as, perhaps most prominently today, clinical psychologist Dr. Robert Epstein:

web.archive org/web/20120522170542/drrobertepstein com/index.php?option=content&task=view&id=10&Itemid=29

Dr. Epstein began his work in this area with a highly important and much discussed article published in an issue of Scientific American Mind entitled "The Myth of the Teen Brain"

Here is a new link to a free copy:

drrobertepstein.com/pdf/Epstein-THE_MYTH_OF_THE_TEEN_BRAIN-Scientific_American_Mind-4-07.pdf

Epstein continued and expanded his studies into the reality of adolescent competency with an extremely groundbreaking book The Case Against Adolescence: Rediscovering the Adult in Every Teen in 2007, and quickly followed it up with an updated and expanded version in 2010, TEEN 2.0: Saving Our Children and Families from the Torment of Adolescence. A list of the various cultural myths our society has of adolescents that Dr. Epstein tackles in his book can be found here:

teen20 com

His Young Person's Bill of Rights, written in celebration of the first annual National Youth Rights Day on April 14th, 2010, can be accessed via a link found on the same page as the preview to Epstein's newest book at this writing.

Though I consider Newt Gingrich, the far right-wing former Speaker of the House of Representatives, to be a mortal political nemesis of mine, I have no choice but to commend him (along with his ideological cohort Rush Limbaugh for the same reason) for coming out in favor of this book and the principles for which it stands, something that I am sad to say is much more than most prominent media pundits of the mainstream Left have done thus far. To quote Gingrich:

"Adolescence is a social experiment that failed. Dr. Epstein's book traces the history of the problem, demonstrates with unrelenting perseverance that much of the turmoil of our teens is a creation of our culture, and offers a specific and detailed proposal for getting our young people back on track. If you are concerned about America's young, and about America's future, this is a must-read."

And as physician and author Deepak Chopra importantly noted about this book: We need to re-examine our basic assumptions about young people, and Epstein shows us how.

Another very important article about youth liberation by Dr. Epstein, this one specifically aimed at how the modern secondary education system that we call high school needs to be dispensed with to a great extent, and which also details the circumstances that led Dr. Epstein to question modern cultural attitudes towards young people and ultimately embracing youth liberation, is his 2007 essay published in an issue of Education Week entitled, "Let's Abolish High School":
 
www drrobertepstein com/downloads/Epstein-Lets_Abolish_High_School-Education_Week-4-4-07.pdf

A very important thing to note here is that in the latter article Dr. Epstein mentions the fact that he is a father of four children, which should further demolish the self-righteous claim of many of those who do not support youth liberation that only people who are not parents could possibly support youth liberation, and that any youth liberationist who becomes a parent will quickly repudiate their support of youth lib, or that that youth liberation is inherently incompatible with and hostile to the institution of parenthood. In fact, Epstein describes in the opening paragraph of this essay that his status as a parent actually led him to embrace youth lib, not automatically reject it, as those who are hostile to or ambivalent about the youth lib platform will often claim.

As all of the above makes clear, there are now serious challenges to the societal assumptions that adolescents are inherently incompetent due to a "faulty" or "underdeveloped" brain, and these challenges are being increasingly supported by a growing number of individuals in the social sciences. These latter social scientists are now being joined by others who are familiar with the history of childhood and how different conceptions of "The Child" in the pre-Victorian era were in comparison to afterwards. And this as opposed to the conception that was adopted since that ideology's paradigm for children became the dominant one in our society, and later expanded to include young adults who are under the arbitrary age of 18.