Human Growth and Development

The somatic nervous system (SNS) controls voluntary movements. It transmits sensory information from the body to the brain and motor commands from the brain to muscles, enabling conscious control over actions. Development of the Brain and Nervous System The brain and nervous system develop through a complex, lifelong process, influenced by genetic, biological, and environmental factors. Understanding the key stages of this development provides insight into how cognitive, motor, and emotional functions evolve from prenatal life through aging. Key points in brain and nervous system development include: Prenatal Development: The brain begins forming early in pregnancy as the neural tube develops into the central nervous system (CNS). By the end of the first trimester, the brain's basic structure is in place, and neurons begin forming. Genetics, maternal health, and environmental factors influence early brain development. Infancy and Early Childhood: The brain grows rapidly in the first few years, forming new neural connections. The sensory and motor areas develop, allowing infants to interact with their surroundings. As children mature, synaptic pruning removes unused connections, while myelination strengthens frequently used ones, improving brain efficiency and specialization.

Cognitive abilities improve through:

●​ Automaticity: Myelination speeds up processing, making behaviors more automatic. ●​ Impulse Control: Development in control regions helps regulate emotions and actions. ●​ Selective Attention: The prefrontal cortex matures, improving focus and reducing distractions.

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