Together, these two processes form primary
afferent fibers that transmit encoded information from periphery to the spinal cord or trigeminal nuclei of the brain stem.
Research on the peripheral neurological mechanism of EA for relieving GI visceral pain has primarily focused on neurons and associated neurotransmitters and
afferent fibers.
Under normal circumstances, pain is associated with electrical activity in small diameter primary
afferent fibers of peripheral nerves.
Sobotka said that studies in kidney transplant recipients indicate that while there is some regrowth of efferent fibers with partial neurologic activity, the outbound
afferent fibers have little or no ability to reconnect.
The PMC controls the descending pathways involved in the micturition reflex, activating or inhibiting the parasympathetic pathways depending on the level of activity in the
afferent fibers (Andersson, 2007).
Renal denervation aims to ablate efferent sympathetic and sensory
afferent fibers of the renal nerves, both of which are thought to contribute to the blood pressure-lowering effect of catheter-based renal denervation (2, 4).
Effect of capsaicin and bradykinin on
afferent fibers with endings in skeletal muscle.
Although the exact mechanism remains elusive, it has been proposed that impulses generated in lesioned peripheral nerve, posterior nerve root/ganglion, or
afferent fibers pass into the spinal cord--some to higher areas to cause pain, while others into the local interneuron and motor neurons to generate involuntary movements of the toes.
A-delta fibers which are small diameter-myelinated and pain-transmitting fiber demonstrate the greatest decrease in conduction velocity in response to the cooling (29), but
afferent fibers that translate the proprioceptive information from muscle spindles to the CNS are type of I[alpha] and II meaning large myelinated fiber that have fast conduction (30).
The vagus is a mixed nerve, containing both efferent fibers (carrying nerve impulse to motor areas) and
afferent fibers (carrying nerve impulse back to the sensory areas--hence the term "affect").
The electrical stimulus activates the large sensory Ia
afferent fibers that travel to the spinal cord and synapse directly onto alpha-motoneurons.