Autonomic Nervous System

• The autonomic nervous system is divided from an anatomical point of view into:

Central

• Located in the skull and vertebral column, consisting of the brain and spinal cord

Peripheral

• Consists of nerves that connect the central nervous system to the body's organs and systems

• Includes ganglia, nerve roots, plexuses, and small nerve fibers

• From a functional point of view, it is divided into:

Somatic

• Controls voluntary conscious functions

Autonomic

• Uses involuntary and unconscious control mechanisms that control the function of the body's organs

• The hypothalamus is a major brain station in which the functions of the autonomic nervous system are integrated with the functions of other neural structures

• From it, nerve impulses descend to the responding body organs

• The fibers of the autonomic motor nervous system are divided into two parts: sympathetic and parasympathetic

• Sympathetic fibers originate from the segments of the brain, starting from the first thoracic segment to the second or third upper lumbar segment

• It is densely distributed in the blood vessels in the heart, lungs, and abdominal viscera

• Parasympathetic fibers originate from the brainstem and run in 4 of its cranial nerves:

  • Oculomotor nerve (III)
  • Facial nerve (VII)
  • Glossopharyngeal nerve (IX)
  • Vagus nerve (X)

• The rest originate from the sacral spinal cord