Development of the Nervous System During Adolescence.

Nervous system development during adolescence is a period of neural remodeling and maturation rather than the initial creation of neural structures, and this involves series of processes such as synaptic pruning and myelination to the prefrontal context development. Adolescent brain maturation is described by the development of executive function facilitated by the prefrontal cortex, e.g., set shifting, planning of goals, and the inhibition of impulsive behavior. The brain's development has mostly been done before adolescence, but it undertakes broad transformation in the adolescent years; the emphasis is no longer on the proliferation of neurons, but on strengthening the network of connections between them. During adolescence, vital processes continue to improve the basic structure to fit the biological and external environments, processes which are dire to the growing progression of the functional integration of frontal regions with the rest of the brain, and these processes enhance neuronal processing and support mature cognitive control of behavior that includes synaptic pruning, increased myelination, prefrontal cortex maturation, limbic system changes, integration of functions, neurotransmitter fluctuations, neuroplasticity, and hormonal influence on brain development. Dramatic alterations in behavior are tied to growth-related variations within the brain, a range of unique characteristics appear during adolescence, such as increased behavioral impulsivity, heightened sensation and novelty seeking, emotion regulation, and social behavior. The power of the environment to shape brain function varies dramatically throughout the life time because neural circuits demonstrate profound plasticity during early life and are later steadied. Environmental and social factors such as the influence of peers, impact of stress and trauma, effect of substance use and role of education, and learning during adolescence can impact upon the development of the nervous system.