Sympathetic nervous system
The Sympathetic nervous system is part of the autonomic nervous system. It becomes more active when you are stressed. It is a part of the "fight or flight" response. The sympathetic nervous system can increase heart rate; make bronchial passages wider; decrease motility (movement) of the large intestine; make blood vessels narrower; increase peristalsis in the esophagus; cause pupil dilation, piloerection (goose bumps) and perspiration (sweating); and raise blood pressure.
Sympathetic Nervous System Media
The sympathetic nervous system extends from the thoracic to lumbar vertebrae and has connections with the thoracic, abdominal, and pelvic plexuses.
Scheme showing structure of a typical spinal nerve. 1. Somatic efferent. 2. Somatic afferent. 3,4,5. Sympathetic efferent. 6,7. Sympathetic afferent.