A (polysynaptic reflex)
has more complex neural pathways that exhibit a number of synapses involving (interneurons) within the reflex arc
What is Monosynaptic reflex?
The monosynaptic stretch reflex, or sometimes also referred to as the muscle stretch reflex, deep tendon reflex, is
a reflex arc that provides direct communication between sensory and motor neurons innervating the muscle
. … This contraction allows the muscle to resist the force that initially caused the reflex.
Is the flexor reflex faster than the stretch reflex?
The time course of polysynaptic flexor reflexes
is slower than stretch reflexes
and represents coordinated activity of motoneuron pools spanning many cord segments.
What is a hypoactive reflex?
Tendon reflexes, also referred to as myotatic reflexes, are variably affected by lower motor neuron lesions. If the complete motor neuron innervation to a muscle is lost, the efferent limb of a tendon reflex will fail. Hypoactive or absent reflexes are commonly
observed in association with lower motor neuron lesions
.
Are Monosynaptic reflexes faster?
This specific type of sensory fiber that carries in the information in the dorsal root for monosynaptic reflexes is
very large, fast, heavily myelinated fibers
. They conduct faster. slowest conducting of all fibers. What feature is unique to the thoracic spinal cord levels?
What is an example of Polysynaptic reflex?
An example of a polysynaptic reflex arc is seen
when a person steps on a tack
—in response, their body must pull that foot up while simultaneously transferring balance to the other leg.
What will happen if we don’t have reflex action?
Most reflexes
don’t have to travel up to your brain to be processed
, which is why they take place so quickly. A reflex action often involves a very simple nervous pathway called a reflex arc. … If the reaction is exaggerated or absent, it may indicate a damage to the central nervous system.
What are the 4 types of reflexes?
In our discussion we will examine four major reflexes that are integrated within the spinal cord:
the stretch reflex, the Golgi tendon reflex, the withdrawal reflex and the crossed extensor reflex
.
Which reflex occurs in response to excessive tension on a tendon?
Functions of
Golgi tendon reflex
The Golgi tendon reflex
is a response to extensive tension on a tendon. It helps avoid strong muscle contractions which could tear the tendon from either the muscle or bone. In sports, quick movements can damage the tendon before the reflex can occur.
What is not required for a reflex arc?
A
reflex does not require any thought input
. The path taken by the nerve impulses in a reflex is called a reflex arc. In higher animals, most sensory neurons do not pass directly into the brain, but synapse in the spinal cord.
What do absent reflexes signify?
When reflex responses are absent this could be a clue that
the spinal cord, nerve root, peripheral nerve, or muscle has been damaged
. When reflex response is abnormal, it may be due to the disruption of the sensory (feeling) or motor (movement) nerves or both.
What is the deep tendon reflex?
Deep tendon reflexes, more properly referred to as
muscle stretch reflexes
, are an integral part of the neurological examination. … In its simplest form, the quick stretch of the muscle-tendon unit stimulates the muscle spindle receptors which, in turn increases the firing of Ia afferents from the spindles.
What causes a deep tendon reflex?
It is common
in stroke, spinal cord injury, cerebral palsy, and multiple sclerosis
. [20] It can also occur after ingesting a large amount of serotonergic drugs. Although the DTR has a sensory component, it does no assess the integrity of the sensory system and is not useful for lesions involving this system.
What is the only Monosynaptic reflex found in the human body?
H-reflex
. There is only one well-studied monosynaptic reflex in adult humans, as illustrated in Figure 3.18. This reflex originates from the primary sensory endings in the muscle spindles.
Which is faster Monosynaptic or Polysynaptic reflex?
Monosynaptic reflexes
are faster compared to polysynaptic reflexes. This is because of the type of sensory fiber that carries information.
Do reflexes involve the brain?
This quick response is called a reflex, and reflexes occur without conscious thinking or planning, meaning
the brain is not involved in them
.
