How do brains stay stable, and when might a dose of flexibility be helpful?

LA JOLLA—Young minds are easily molded. Each new experience rewires a child’s brain circuitry, adding and removing synaptic connections between neurons. These wiring patterns become more stable with age, but biology has left some wiggle room to ensure that adult brains can still adapt and refine their circuitry as needed. This flexibility is called neuroplasticity, and our ability to learn, make new memories, and recover from injury all depend on it.

So how does your brain know how flexible to be at different points in life? Could we target these mechanisms to open up new periods of plasticity in adulthood or use them to treat brain injuries, diseases, and disorders? What cells, genes, and molecules control the stability of your neural circuits?