A Delta Fibers
A delta fibers are sensory nerve fibers in the body,
which means that they transmit sensory information
(specifically the sensations of pressure and cold). A
delta fibers stimulate pain receptors (known as
nociceptors), which helps rapidly communicate initial
information about pain to the body. These signals are
sent to the brain and spinal cord and are usually
perceived as acute, sharp pain.

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A Delta Fibers are 2nd to Right
A delta fibers are thinly myelinated, which means they are covered with a fatty substance
called myelin. Myelin covers nerves and helps them transmit messages fast. A delta
fibers conduct impulses at a speed of 2 to 30 meters per second, which is moderately
fast (referred to as moderate conduction velocity), since a meter is approximately 39
inches (slightly more than 3 feet).

Compare a fibers to c fibers, which do not have myelin and thus do not transmit
information as fast. C fibers carry slow burning chronic pain sensations and are
unmyelinated. A delta fibers are 1 to 22 micrometers (one millionth of a meter) in
diameter, which is very small. A delta fibers are also known as a-fibers or a-ð (the Greek
letter "delta") fibers. The Greek letter "delta" corresponds to the letter "D" in the English
alphabet. ð is the lowercase version of delta.
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