Early adulthood spans the ages of 18 to 25 years. Physically, young adults experience stabilization of physical characteristics. The wisdom teeth are usually fully developed by the end of early adulthood, and the rate of neural growth tapers off near the end of this developmental phase. Young adults reach a balanced and stable sexual hormone composition, as the adolescent flood of testosterone and estrogen begin to taper off as well.
Subjectively, young adults are very focused on their identities. They spend a great deal of cognitive and emotional resources on the question of who they are and what their place is in society. Early adulthood is marked by an experimental stance toward identity. Young adults often play with their gender identity, professional identity, and religious, social, and cultural identifies.
It is a time where individuals essentially "try on" different identities and then use social feedback and their own emotional experience to see which one "fits."