11/3/2026
Yesterday, while reading about children's brain development, I came across something both interesting and useful. It also made me think about how the adult brain learns and changes. Although children's brains are still developing, the underlying mechanisms of learning and brain plasticity are relevant to adults as well.
Almost every topic concerning children's development can be better understood by looking at one underlying mechanism: how the brain develops through learning and experience.
This mechanism applies throughout childhood and adolescence, from birth to age 18 and beyond.
First, here learning is not limited to acquiring knowledge from textbooks. It has a much broader meaning. A child learning to speak, walk, interact with others, or solve problems is also learning. All these abilities develop through changes in the brain's neural networks.
In simple terms, learning involves the formation and modification of connections between neurons. Every day, in different settings, we encounter new information and experiences. Reading a book, hearing a sentence, solving a problem, or practicing a physical movement can all change the way neurons communicate with one another.
Some neural connections are temporary, while others become stronger and more stable through repeated activity and experience. As these connections are strengthened and neural networks become more efficient, we acquire new knowledge and abilities. That is what is going on when we learn.
Two important concepts help explain what this means for children and how the developing brain changes: synaptogenesis and synaptic pruning.
What is a synapse?
The human brain contains approximately 86 billion neurons. These nerve cells communicate with one another through specialized junctions called synapses. A synapse allows signals to pass from one neuron to another, making communication within the brain possible.
1. Synaptogenesis: Building connections
Synaptogenesis is the process by which new synapses form between neurons. It occurs especially rapidly during certain periods of early brain development.
As children experience the world, their brains develop and modify connections that support new abilities. For example, when a baby hears language, practices moving, or interacts with caregivers, neural networks involved in hearing, movement, and social interaction are being shaped by these experiences.
2. Synaptic pruning: Refining connections
The developing brain does not retain every connection it forms. Some connections are weakened or eliminated through a process called synaptic pruning.
Think of it as pruning the branches of a tree. A gardener removes some branches so that the remaining ones can grow more effectively. Similarly, the brain refines its neural networks, strengthening useful patterns of communication and eliminating some connections that are less useful.
Experience and patterns of neural activity help determine which connections are strengthened and which are eventually removed. This process makes neural networks more organized and efficient.
Why does timing matter?
Brain development follows a timeline. Different brain regions develop and mature at different rates. Some neural systems develop rapidly in early childhood, while others, particularly those involved in planning, decision-making, and self-control, continue developing through adolescence and into young adulthood.
This makes childhood and adolescence particularly important periods for brain development. During these years, the brain is highly adaptable and responsive to experience.
Understanding these processes helps explain why children's experiences matter so much—and why learning remains possible throughout life.
But development does not stop when a person reaches adulthood. The adult brain can still form and modify neural connections, allowing people to acquire new knowledge, develop skills, and adapt to changing circumstances. This ability is known as neuroplasticity.
A Chinese saying that fits well here: 活到老，学到老 (Huó dào lǎo, xué dào lǎo) “Live and learn as long as you live.” This saying connects childhood brain development with lifelong learning. Children learn as their brains develop, but adults never lose the ability to learn and change.
Tomorrow, I will explore how the adult brain learns and how its capacity for change compares with that of a developing brain.
