In addition to parasympathetic and sympathetics, visceral afferent (sensory) fibers are often included during a discussion of autonomics because of their similar pathways of distribution. Visceral afferent (sensory) fibers also need to reach all organs within the pelvis. These fibers, originating within the spinal cord, accompany visceral efferent fibers throughout their pathways. Afferent fibers, important in reflex and visceral function, are also important in conducting visceral pain impulses. We are usually unaware of the sensory input of these fibers, which provides the central nervous system information about the condition of the body's internal environment. Conscious visceral sensation is usually categorized as pain and is poorly localized. (For more information, please see the introduction to autonomics module.)
|
