How stress hormone shapes brain development: New clues to why early plasticity fades

Researchers have discovered a new way that brain plasticity is controlled in early life, offering insight into the little-understood phenomenon of critical-period closure. In the months or years after birth, critical periods of learning in the brain are open, making the organ uniquely sensitive to information coming from the outside world. Experiences during this time can have a lasting impact on the brain by sculpting neural connections that persist into adulthood. As a child or young animal matures, this heightened period of brain plasticity ends as critical periods begin to close through mechanisms that remain largely unclear.