As part of their development into young adults, humans must develop an identity independent from their parents or family and a capacity for independent decision-making. They may experiment with different roles, behaviors, and ideologies as part of this process of developing an identity.Teenage rebellion has been recognized within psychology as a set of behavioral traits that supersede class, culture, or race; some psychologists, however, have disputed the universality of the phenomenon.
There remains some debate as to whether the causes of teenage rebellion are completely natural or necessary. Some posit that an adolescent's failure to achieve a sense of identity can result in role confusion and an inability to choose a vocation, and/or that these pressures may develop from being viewed as adults. Indeed, in the Western world the age at which one is considered an adult (in both the cultural and legal sense) has advanced from the early teens in earlier centuries to the late teens – or even, in today's society, one's early twenties.
In Scientific American, however, Harvard psychologist Robert Epstein disparaged the notion of "the immature brain that supposedly causes teen problems" as largely a myth, and wrote that the turbulence often seen as typical of these years is not "a universal developmental phenomenon." Epstein alternatively contends that external factors – notably "treating older and older people as children while also isolating them from adults and passing laws to restrict their behavior" – are more likely responsible for the angst seen among many American teens. Likewise, in an article by Robin Lustig of BBC, academic Cynthia Lightfoot states that what is now considered youth culture was created by the advent of compulsory formal education in the United States, due to the unprecedented separation of younger and older people that resulted from it. Lustig notes that the efflorescence of rebellious attitudes in teenagers of other countries has been concurrent with the introduction of Western culture into those countries.
Temple University psychologist Laurence Steinberg suggests that "stopping systems within the brain make adolescents more susceptible to engaging in risky or dangerous behavior." He argues that social programs and measures discouraging youth from taking part in risky behavior (such as drug and alcohol abuse, reckless driving, and unsafe sex) have been largely ineffective.