General visceral fibers

General visceral fibers (GVF) are a type of autonomic nervous system fibers that innervate the smooth muscle and glands of the body's internal organs. They are responsible for the unconscious regulation of the body's internal environment, including heart rate, digestion, and respiratory rate.

Anatomy

General visceral fibers originate from the brainstem and the spinal cord. They are part of the autonomic nervous system, which is divided into the sympathetic nervous system and the parasympathetic nervous system.

The sympathetic fibers, also known as thoracolumbar fibers, originate from the thoracic and lumbar regions of the spinal cord. They are responsible for the body's "fight or flight" response, increasing heart rate, dilating the pupils, and slowing digestion.

The parasympathetic fibers, also known as craniosacral fibers, originate from the brainstem and the sacral region of the spinal cord. They are responsible for the body's "rest and digest" response, slowing heart rate, constricting the pupils, and increasing digestion.

Function

General visceral fibers carry both afferent (sensory) and efferent (motor) signals. The afferent fibers carry sensory information from the internal organs to the central nervous system. This information is used to regulate the body's internal environment, including blood pressure, pH, and oxygen levels.

The efferent fibers carry motor signals from the central nervous system to the internal organs. These signals control the function of the organs, including heart rate, digestion, and respiratory rate.

Clinical significance

Dysfunction of the general visceral fibers can lead to a variety of disorders, including autonomic neuropathy, orthostatic hypotension, and irritable bowel syndrome. Treatment of these disorders often involves managing the symptoms and addressing the underlying cause.