reflex arc


Also found in: Dictionary, Thesaurus, Encyclopedia, Wikipedia.

arc

 [ahrk]
a part of the circumference of a circle, or a regularly curved line.
binauricular arc the arc across the top of the head from one auricular point to the other.
reflex arc the circuit traveled by impulses producing a reflex action: receptor organ, afferent nerve, nerve center, efferent nerve, effector organ in a muscle; see also reflex.
Three-neuron reflex arc. From Dorland's, 2000.

re·flex arc

1. the route followed by nerve impulses in the production of a reflex act, from the peripheral receptor organ through the afferent nerve to the central nervous system synapse and then through the efferent nerve to the effector organ.
2. a neural pathway that involes both the peripheral and central nervous systems.

reflex arc

n. Physiology
The neural path of a reflex.

reflex arc

Etymology: L, reflectere, to bend back, arcus, bow
a simple neurological unit of a sensory neuron that carries a stimulus impulse to the spinal cord, where it connects with a motor neuron that carries the reflex impulse back to an appropriate muscle or gland.
enlarge picture
Reflex arc

reflex arc

Neurology The basic conduction pathway through the nervous system, consisting of a sensory neuron, an association neuron, and a motor neuron

re·flex arc

(rē'fleks ahrk)
The route followed by nerve impulses in the production of a reflex act, from the peripheral receptor organ through the afferent nerve to the central nervous system synapse and then through the efferent nerve to the effector organ.
Enlarge picture
REFLEX ARC FOR PATELLAR TENDON REFLEX

reflex arc

The path followed by a nerve impulse to produce a reflex action. The impulse originates in a receptor at the point of stimulation, passes through an afferent neuron or neurons to a reflex center in the brain or spinal cord, and from the center out through efferent neurons to the effector organ, where the response occurs.
See: illustration
See also: arc
Reflex arcclick for a larger image
Fig. 267 Reflex arc . The arrows indicate the direction of impulse from receptor to effector.

reflex arc

the nervous connections between RECEPTOR and EFFECTOR that result in a simple response being elicited by a specific stimulus (a reflex action), such as a knee jerk without the involvement of the brain. The receptor is excited by a stimulus which induces a nerve impulse in the DENDRITE of a sensory (afferent) NEURONE. This passes through the cell body in the dorsal root ganglion and on along the sensory AXON to the SPINAL CORD. There it crosses a SYNAPSE, usually to an intermediate neurone which synapses with the efferent neurone and passes out of the spinal cord via the ventral root along the axon of the motor (efferent) neurone to the effector which produces the stereotyped response. Most reflexes involve more than one synapse, i.e. are polysynaptic, but those concerned with posture are often monosynaptic, such as the knee-jerk reflex. See Fig. 267 . see RAMUS COMMUNICANS.

reflex arc

route followed by nerve impulses to facilitate a reflex action/reaction; impulse travels from site of stimulus along a peripheral afferent nerve, through the central nervous system (CNS), thence along the efferent nerve to stimulate/cause an effect in the effector organ; may be a monosynaptic system, i.e. one CNS synapse between afferent and efferent nerve; or polysynaptic, i.e. incoming nerve impulse synapses with two or more neurones, including other CNS neurones, allowing subsequent conscious awareness of the stimulus

reflex arc,

n the smallest functional unit of the nervous system that consists of two or more neurons (afferent and efferent) and can react to a stimulus.
Enlarge picture
Reflex arc.

re·flex arc

(rē'fleks ahrk)
1. Route followed by nerve impulses in production of a reflex act, from peripheral receptor organ through afferent nerve to central nervous system synapse and then through efferent nerve to effector organ.
2. Neural pathway that involes both peripheral and central nervous systems.

arc

a part of the circumference of a circle, or a regularly curved line.

binauricular arc
the arc across the top of the head from one auricular point to the other.
reflex arc
the circuit traveled by impulses producing a reflex action: from the receptor organ, through the afferent nerve, nerve center, efferent nerve, to the effector organ.
References in periodicals archive ?
2) They act on the hiccup reflex arc by counteracting the stimulatory impulses, blocking the transmission of nerve impulses, or affecting the underlying causes.
It triggers a set of nerves in your throat and mouth that are responsible for the hiccup reflex arc," said Mallory with a matter-of-fact tone.
These abnormalities may be either at the level of nerve roots, cranial, peripheral, and autonomic nerves, or the reflex arc between the inspiratory and glottic closure complexes.