Teens and Young Adults: Typical Development

Below you will find a brief review of typical development, divided into four sections, each describing a different aspect of development.

  • The next page describes the impact of trauma on each of these aspects of development.
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Physical Development

Physical changes associated with puberty occur in early adolescence (ages 10-14 for girls, and 12-16 for boys), and prepare young bodies for sexual reproduction. Influenced by estrogen, most girls experience breast budding and the emergence of pubic hair as the first signs of puberty, followed by the onset of menstruation within  two years. In boys, the production of testosterone, causes their testes to enlarge and create mature sperms cells. Both boys and girls typically undergo significant growth spurts throughout puberty.  The brain also undergoes significant growth during this time. The moodiness and impulsivity of adolescence reflects underlying neurological changes that are calmed in young adulthood by the growth of the pre-frontal cortex, which assists with judgment, impulse control, emotional regulation and long-term planning. These functions promote success in occupational, academic, and inter-personal domains.


Cognitive Development

The decision-making of early adolescence typically focuses on the immediate environment, including self, home, and school. The mid-teens bring more sophisticated thinking and an increased capacity for abstract approaches to problem solving. As they approach adulthood, adolescents can appreciate the possibility of multiple perspectives and begin to grapple with complex ethical and social issues.  Young adulthood is a critical stage for the solidification of complex forms of thinking. The increased capacity to reflect on one’s own mental states and those of others simultaneously can contribute to smoother social interactions as adolescents and young adults are better able to understand that others might share in or differ from their own perspectives or emotions. Young adults can organize multiples views about themselves while appreciating that others might experience themselves and the world in radically different ways.


Social Development

One of the most obvious changes in adolescence is that the hub around which the adolescent’s world revolves shifts from the family to the peer group. Partly through this increased identification with peers, adolescents begin to develop moral judgment and to define the ways in they differ from their parents and other important adults. Peer groups also serve to reinforce status, popularity, and acceptance.  By young adulthood, peer groups have often been replaced by more intimate dyadic relationships, such as one-on-one friendships, and committed sexual relationships.  Caregivers’ acceptance and validation of the young adult status is crucial at this stage, although cultural norms around this vary. Even with the increasing need for autonomy, young adults may also have a continuing need for support from caregivers, even if to a lesser degree than during earlier phases of adolescence.


Emotional Development

Emotional development during adolescence involves establishing a coherent identity, which includes both present and future self-images. Adolescents tend to explore or  “try on” personas, allowing them to experiment with different behavior and values. Typically, adolescents have a strong desire to be accepted by their peers, who can provide recognition and help to shape their perspectives.  Young adulthood is typically a time for solidifying one’s identity. This is made easier by the increased capacity for impulse control and emotional regulation, which contributes to “putting the brakes on” sensation-seeking behavior that arises in puberty. Young adults are more prepared to explore the possibilities of furthering their education, finding employment, and forming intimate relationships. These are all influenced by the increased capacity to adequately manage emotions and behavior.



Teens and Young Adults: The Impact of Trauma on Development »