C fibers are sensory fibers in the body, which means
that they transmit sensory information. C fibers are
specifically known to transmit slow burning pain,
warmth, sensual touch, itching, and burning/cramping
from muscle exercise. They respond to stimuli with
strong intensity and are responsible for slow, dull,
chronic pain. C fibers are present in peripheral nerves
(nerves outside of the brain and spine). C fibers are
known as afferent nerves, which means that the send
information to the central nervous system (brain and
C-fibers are to the right.
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C fibers stimulate pain receptors (known as nociceptors), which helps communicate initial
information about pain to the body. C fibers are unmyelinated, which means they lack
myelin, a fatty substance that covers nerves which helps them transmit messages fast.
Thus, c fibers are slow due to the lack of myelin. Specifically, c fibers conduct impulses
slowly (known as slow conduction velocity) at a speed of no more than two meters per
second. A meter is approximately 39 inches (slightly more than 3 feet).

C fibers are 0.2 to 1.5 micrometers (one millionth of a meter) in diameter, which means
they are really, really, really small. Compare c fibers to a delta fibers, which are
myelinated and thus transmit sensory information fast, which is perceived as acute sharp
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