Plasticity in the brain refers to the ability to generate new neurons and new connections between neurons. This is important for learning, memory, and recovery from damage. There is some question as to whether humans and mice are at all similar when it comes to the ability to generate new neurons in adulthood, but in either species overall plasticity declines with age, and this is thought to be an important contributing factor in cognitive decline. This decline isn’t simple, however, as illustrated by the research results here. Like many aspects of aging, it may be more of a ragged dysregulation, a running awry of mechanisms that operated correctly in youth, rather than a matter of a process slowly and cleanly shutting down.
Neuroplasticity refers to the brain’s ability to modify its connections and function in response to environmental demands, an important process in learning. Plasticity in the young brain is very strong as we learn to map our surroundings using the senses. As we grow older, plasticity decreases to stabilize what we have already learned. This stabilization is partly controlled by a neurotransmitter called gamma-Aminobutyric acid (GAB), which inhibits neuronal activity.