What are the 2 types of nerve fibers that conduct pain impulses?
Generally, the electrical impulses that travel along the axons can be projected in two ways—the afferent or efferent nerve fibers.
Which nerve fibres carry pain?
A-beta nerve fibers carry information related to touch. A-delta nerve fibers carry information related to pain and temperature.
What are a-delta and C fibers?
A-delta fibers are small-diameter (1 to 6 μm), myelinated primary afferent fibers; C fibers are smaller-diameter (1.0 μm) unmyelinated primary afferents. The A-delta fibers conduct at velocities between 5 and 25 milliseconds; C fibers conduct at 1.0 μm/sec.
What are the types of pain receptors and fibers?
Muscle pain is mediated by receptors of both group III (thinly myelinated; Aδ fibers) and group IV (nonmyelinated; C fibers) afferent fibers. Excessive stretch or contraction after strenuous exertion may activate the muscle pain receptors of group III fibers.
What is C fibers?
C fibers are one class of nerve fiber found in the nerves of the somatic sensory system. They are afferent fibers, conveying input signals from the periphery to the central nervous system.
What are the two types of nociceptors?
The first type is termed high threshold mechanonociceptors or specific nociceptors. These nociceptors respond only to intense mechanical stimulation such as pinching, cutting or stretching. The second type is the thermal nociceptors, which respond to the above stimuli as well as to thermal stimuli.
What are C fibers in pain?
C fibers respond to stimuli which have stronger intensities and are the ones to account for the slow, lasting and spread out second pain. These fibers are virtually unmyelinated and their conduction velocity is, as a result, much slower which is why they presumably conduct a slower sensation of pain.
What do type B nerve fibers do?
Fibers of the B group are myelinated with a small diameter and have a low conduction velocity. The primary role of B fibers is to transmit autonomic information. Fibers of the C group are unmyelinated, have a small diameter, and low conduction velocity.
What are D fibers?
Fibres which are dyeable with disperse dyes are called D-fibres, e.g., polyester, nylon, acrylic secondary acetate and cellulose triacetate.
What are Type A fibers?
Type Aα fibers include the type Ia and type Ib sensory fibers of the alternative classification system, and are the fibers from muscle spindle endings and the Golgi tendon, respectively. Type Aβ fibres, and type Aγ, are the type II afferent fibers from stretch receptors.
What are the two pain pathways?
Thus there are two major ascending pathways for pain: a direct lateral spinothalamic pathway and an indirect medial spinoreticulothalamic pathway.
What do B fibers do?