Adolescent Development Notes

Adolescent Development Overview

  • Adolescence: Transition from childhood to adulthood, encompassing physical, emotional, and social changes.

  • Puberty: A key stage in adolescence marked by sexual maturation and reproductive capability.

  • Menarche: The first menstrual period in girls, signaling the onset of menstruation during puberty.

What is Puberty?


  • A period characterized by:

  • Sexual maturation.
  • Sequence of physical changes, though timing may vary.
  • Changes such as breast development in girls and spermarche (first ejaculation) in boys.


  • Key Milestones in Sexual Development:

    Age (Years)GirlsBoys
    8Breast buddingGrowth of scrotum/testes
    9Growth of pubic hairChange in voice
    10Growth spurtLengthening of penis
    11Peak growthGrowth of pubic hair
    12First period (menarche)Growth spurt
    13Growth of underarm hairGrowth of facial hair
  • Brain Development During Puberty

    • The adolescent brain experiences significant changes, including:

      • Connection Growth: Increased neuronal connections up to puberty, then selective pruning occurs during adolescence.
      • Frontal Lobes: Continued development enhances:
      • Judgment
      • Impulse control
      • Long-term planning due to myelination of axons.
    • A study on sensation seeking among 12-24 year-olds reveals:

      • Peak sensation seeking occurs during mid-teens.
      • Impulse control develops more gradually as the frontal lobes mature.

    Adolescents' Thought Processes

    • Early teens often display self-focused reasoning:
      • A belief that their experiences are unique (e.g., feeling misunderstood by parents).
      • Imaginary Audience: The feeling that others are constantly observing and judging them.
      • Personal Fable: The belief in their own uniqueness, often leading to risky behaviors.

    Emotional Changes: Mood Swings and Anxiety

    • Characteristics of Puberty:
      • Mood swings and anxiety due to stress, regulated by GABA (an inhibitory neurotransmitter).
      • Stress leads to THP release which interacts with GABA, notably differing in effects on adolescents versus adults:
      • In adults, THP calms; in adolescents, it raises anxiety due to receptor expression changes in the hippocampus.

    Identity Formation in Adolescents

    • Identity: The sense of self, described by Erikson as the task of solidifying self-concept.
    • Exploration of Identity:
      • Trying out various roles in different contexts (home, school, online).
    Types of Identity Status (Erikson)
    • Identity Achievement: Experienced crisis and made a commitment.
    • Identity Moratorium: Experienced crisis but failed to commit.
    • Identity Foreclosure: No crisis but made a commitment.
    • Identity Diffusion: Neither crisis nor commitment.

    Social Identity

    • The aspect of self-concept derived from group memberships, influenced by differences with others.

    Historical Context of Adulthood

    • Past (1890s): Women typically transitioned to adulthood about 7 years after menarche (first period).
    • Present (2006): The period between menarche and marriage has increased to about 14 years in industrialized countries.