Afferent nerve fiber | |
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Details | |
Identifiers | |
Latin | neurofibrae afferentes |
Code | TH H2.00.06.1.00015 |
TA | A14.2.00.017 |
FMA | 76570 |
Anatomical terms of neuroanatomy
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In the peripheral nervous system (PNS), an afferent nerve fiber is the axon of a sensory neuron. It is a long process extending far from the nerve cell body that carries an action potential from the sensory neuron toward the central nervous system (CNS). Bundles of these axons form a nerve known as an afferent nerve, or sensory nerve.
The opposite direction of neural activity is efferent conduction. The efferent nerve fiber is the axon of a motor neuron. Bundles of these axons form a motor nerve, or efferent nerve.
In the nervous system there is a "closed loop" system of sensation, decision, and reactions. This process is carried out through the activity of sensory neurons, interneurons, and motor neurons.
A touch or painful stimulus, for example, creates a sensation in the brain only after information about the stimulus travels there via afferent nerve pathways. Afferent neurons are pseudounipolar neurons that have a single long axon with a short central and a long peripheral branch. These cells do not have dendrites. They have a smooth and rounded cell body. Just outside the spinal cord, thousands of afferent neuronal cell bodies are aggregated in a swelling in the dorsal root known as the dorsal root ganglion.