Segment of Autonomic Nervous System

SEGMENTS OF ANS

  • The ANS is divided into small segments after its origin from CNS.
  • Three segments are evident:
    • Cranial segment
      • From brain stem with nerve fibers of oculomotor, facial, Glossopharyngeal & Vagus
    • Thoraco lumbar segment
      • From spinal cord with ventral root of spinal nerves from T1 or L5or6 segments.
    • Sacral segment
      • From spinal cord and the ventral root of S1-S3 Sacral nerves.
      • Preganglonic axons of the parasympathetic division originate in the cell bodies of the brain stem (cranial out flow) and in the terminal segment of (sacral out flow ) of the spinal cord .
Last modified: Saturday, 28 May 2011, 9:24 AM