Efferent nerve fiber

Efferent (from Latin effere " also carry out lead " ) are neurophysiologically those appendages called neurons, are transmitted via the signals away from a specific area and to other cells. This general labeling according to the direction of the signal line can be used for different structures at different levels.

At the cellular level in relation to the nerve cell bodies of the axon is called efferent. At the regional level, based on a specific region of the brain called each outgoing paths also efferent fibers in contrast to the incoming afferents.

In relation to the systemic level on the central nervous system (CNS ), the exiting nerve fibers through which signals emanate, as a whole efferent nerve fibers or " efferent " and divided into somatic and visceral. These afferents are compared with the input signal. As components of a reflex arc is ever spoken of afferent or efferent limb. Based on the direction of the signal line afferents are the counterpart of efferent nerve fibers and thus, via the signals from other cells of a nerve cell afferent flow to (whose perikaryon example, in the CNS is ).

Efferent fibers from the CNS

Areas in the central nervous system - a brain region or spinal cord segment - receive signals via afferent fibers, process it and can efferent signals to various other core areas of the brain and / or spinal cord to pass.

In certain core areas - the ( motor ) core columns of the spinal cord and ( motor ) nuclei of cranial nerves - are neurons whose axons enter from the CNS. In the ventral roots of spinal nerves and cranial nerves with some of these nerve fibers leave the central area, forming portions of ( peripheral ) nerves or nerve branches of the peripheral nervous system. These efferent nerve fibers are collectively referred to as efferent fibers ( at the systemic level ). They include, inter alia, the ( motor ) nerve fibers that transmit signals to skeletal muscles and smooth muscles. Depending on the success of this organ efferents then take on different services influence. According to their destinations efferents can be further distinguished.

The somatic efferent fibers (SE, from Latin soma " body " ) are motor nerve fibers ( motor neurons ) of the skeletal muscles and belong to the somatic nervous system; they are also referred to as somatomotorisch.

The visceral efferent (from Latin viscera, " entrails " ), however, are part of the autonomic nervous system and are also referred to as viszeromotorisch. Some authors further distinguish them in the general visceral efferent fibers (AVE; engl LSU. General visceral efferent ) and the special visceral efferent (SVE ) divided. The AVE transmit information to smooth muscles, cardiac muscles and glands. The SVE innervate the muscles derived from the branchial arches ( " Branchialmotorische efferent " ), ie the masticatory muscles, the muscles of facial expression, the muscles of the pharynx and larynx and the sternocleidomastoid muscle and the trapezius muscle.