Lab Exam Three: Reflex Physiology Flashcards
Relexes:
fast reactions of glands or muscles stimulation
What are the general properties of a reflex?
- stimulation requirement
- quick
- involuntary
- stereotyped
Inborn (intrinsic) reflex:
rapid, predictable motor response to a stimulus
An inborn reflex is […] as it is built into our […] anatomy which is regulated by the […] and spinal cord.
unlearned; neural; brain stem
Learned (acquired) reflex:
results from practice or repetition
What is an example of a learned reflex?
driving a car
T/F: You cannot modify inborn reflexes.
false
both types of reflexes can be modified by conscious effort
What is the process of a stimulus?
receptor –> sensory neuron –> integration center –> motor neuron –> effector
What are the two functional classifications?
- somatic reflexes
2. autonomic reflexes
Somatic reflexes:
if they activate skeletal muscle
Autonomic reflexes:
if they activate visceral effectors
List visceral effectors:
smooth, cardiac muscle, glands
What can spinal reflexes be classified as?
somatic reflexes
The most commonly assessed reflexes are…
- stretch reflex
- flexor reflex
- superficial reflexes
When does spinal shock occur? What is its effect?
when the spinal cord is transected
immediately depresses all functions controlled by the cord
Muscle spindles:
stretch receptors embedded in the muscles
Muscle spindles can also be referred as…
proprioceptors
What is the function of muscle spindles?
inform the brain of muscle length and body movements
Muscle spindles– The brain sends […] back to the muscles that control […], posture, […], and corrective reflexes.
motor command; muscle tone; coordinated movement
When a muscle is suddenly stretched what occurs?
contraction occurs, increase of tone, and feels
What is the purpose of the stretch reflex?
helps to maintain equilibrium and posture
Tendon organs are […] located in a tendon near its junction with a […].
proprioceptors; muscle
Tendon reflex:
response to excessive tension on the tendon
What is the purpose of the tendon reflex?
serves to moderate muscle contraction before it tears a tendon
Tendon organs measure…
tension
Flexor reflex:
quick contraction of flexor muscles
What does a flexor reflex result in?
withdraw of a limb from an injurious stimulus
Crossed extension reflex:
contraction of extensor muscles in the limb opposite from the one that is withdrawn
The crossed extension reflex […] that limb and enables you to […].
extends; keep your balance
Superficial reflexes:
elicited by gentle cutaneous stimulation
Plantar reflex tests integrity of spinal cord from […] and […].
L4-S2; corticospinal tracts
Normal plantar reflex response:
toes flex
Abnormal plantar reflex response:
toes dorsiflex to great toe and the smaller toes fan laterally
Abnormal plantar reflex is also known as…
Babinski’s sign
What are the two superficial reflexes?
- plantar reflex
2. abdominal reflex
Abdominal reflex checks the integrity of the […] and ventral rami from […] and […] tracts.
spinal cord; T8-T12; corticospinal
Stroking the skin of the lateral abdomen above the umbilicus…
induces a movement of the umbilicus toward the stimulated site
