Reflex arc
Arcus reflexus
Definition
"A reflex arc is a neural pathway that controls an action reflex. Most sensory neurons do not pass directly into the brain, but synapse in the spinal cord. This characteristic allows reflex actions to occur relatively quickly by activating spinal motor neurons without the delay of routing signals through the brain, although the brain will receive sensory input while the reflex action occurs.
There are two types of reflex arc :
- autonomic reflex arc (affecting inner organs)
- somatic reflex arc (affecting muscles)
References
This definition incorporates text from a public domain edition of Gray's Anatomy (20th U.S. edition of Gray's Anatomy of the Human Body, published in 1918 – from http://www.bartleby.com/107/).
