How can neuroplasticity cause helpful or harmful brain reorganization?

Neuroplasticity is the capacity of neurons and neural networks to reorganize their connections and behavior in response to development, learning, or injury. This fundamental property relies on adjusting the strength or number of synapses between neurons.1

Helpful Reorganization

Neuroplasticity is often beneficial, allowing the brain to adapt efficiently to its environment. During development, the brain undergoes synaptic pruning, where unused connections are eliminated to create efficient neural pathways. In adulthood, this mechanism supports learning and memory by reinforcing connections through experience. Furthermore, following physical damage such as a stroke, the brain can reorganize to compensate for lost activity, a process that researchers aim to harness through therapeutic techniques and stem cell research.12

Harmful Reorganization

Reorganization can also be negative. Because the same mechanisms drive plasticity regardless of the outcome, the brain may adapt to dysfunction or sensory loss in ways that are not helpful. For instance, if the nervous system does not receive appropriate sensory input during critical periods of development, it may fail to develop properly.12