neurodevelopment

Neurodevelopment is the biological process that forms the structure and function of the nervous system from conception through maturation. It encompasses the growth and organization of neurons, glial cells, and synaptic connections that underlie cognition, emotion, and behavior. Early development begins with the formation of the neural tube, followed by neurogenesis, the birth of neurons, and neuronal migration to distinct cortical and subcortical regions. Differentiation leads to specialized neuronal and glial cell types, while axon guidance and synaptogenesis establish functional circuits. Synaptic pruning refines connectivity during childhood and adolescence, and myelination increases the speed and efficiency of neural signaling.

Development proceeds along genetic and environmental axes. Genetic programs regulate timing and patterning, while epigenetic and activity-dependent mechanisms shape maturation in response to experience. Nutrition, maternal health, toxins, infections, and psychosocial factors can influence trajectories, sometimes increasing risk for neurodevelopmental disorders. Commonly studied conditions include autism spectrum disorder, ADHD, intellectual and developmental disabilities, cerebral palsy, and language or learning disorders; these arise from complex interactions among genes, brain development, and environment.

Throughout development, plasticity allows circuits to adapt to experience, with periods of heightened sensitivity known as critical or sensitive periods. After early childhood, continued maturation occurs in frontal and association networks, supporting executive function, social behavior, and higher cognitive processes. Neurodevelopment research utilizes human longitudinal studies and animal models, alongside neuroimaging, electrophysiology, and molecular methods, to map normal trajectories, identify deviations, and inform interventions designed to promote healthy development and mitigate impairments.