Superior cervical ganglion

Definition

The superior cervical ganglion is the largest and most cranial of the cervical ganglia, part of the sympathetic nervous system, located near the top of the spinal column in the neck. It controls various physiological responses such as pupil dilation, sweating, and blood vessel constriction in the head and neck.

Related terms

Autonomic Nervous System: A part of the peripheral nervous system that controls involuntary body functions like heartbeat and digestion.

Sympathetic Nervous System: A division of the autonomic nervous system responsible for mobilizing body systems during activity or stress, often described as enabling “fight or flight” responses.

Parasympathetic Nervous System: Another division of the autonomic nervous system, which conserves energy by slowing down heart rate, increasing intestinal and gland activity, and relaxing sphincter muscles; it supports “rest and digest” functions