Adolescence and Puberty

The transition from a child’s body to an adult’s. Puberty is the biological process of sexual maturation; adolescence is the broader life stage surrounding it.

What is happening

• The hormonal trigger — after lying quiet through childhood, the HPG axis reawakens, and rising sex hormones set the changes in motion.
• Sexual maturation — the reproductive organs mature and become functional; secondary sex characteristics appear.
• The growth spurt — a rapid acceleration in height, followed by the fusing of the bones’ growth plates, after which adult height is essentially fixed.
• Brain remodeling — the brain continues to mature into the mid-twenties, with the planning and impulse-control regions maturing last.

Why it matters

This is the second-fastest period of change after prenatal life, and the only one the person experiences consciously. Body, mind, and social role all shift at once.