Week 9 - Reflexes Flashcards
Describe the stretch reflex
Contraction of the muscle as a response to muscle stretching
Testing stretch and tendon reflexes of the biceps brachii involves which dermatomes?
C5-C6
Testing stretch and tendon reflexes of the triceps brachii involves which dermatomes?
C6-C8
Testing stretch and tendon reflexes of the quadriceps femoris involves which dermatomes?
L2-L4
Testing stretch and tendon reflexes of the gastrocnemius involves which dermatomes?
S1-S2
Describe the tendon reflex
Relaxation of agonist muscle, Contraction of antagonist muscle
The stretch reflex is a ________ reflex
monosynaptic
Describe the Flexor/Withdrawal reflex arc
- noxious stimuli (pain) -> afferent branch synapses on inter-neuron
- somatic motor neurons to a) the same side muscles: flexion/withdrawal and b) somatic motor neurons to opposite side muscles
- cross extension
The blood supply of the spinal cord consists of _______
one anterior and two posterior spinal arteries
The gag (aka _______) reflex sensory input via ______ and motor reaction as gagging via ______
pharyngeal
CN IX - Glossopharyngeal
CN X - Vagus
The tendon reflex is a ________ reflex
polysynaptic
Which anterior rami do not participate in peripheral nerve plexi?
T2 - T12
The cervical plexus includes anterior rami of _______. Notable nerves arising from the cervical plexus include _______
C1-C5
Ansa cervicalis, phrenic
Which cranial nerves join the cervical plexus?
CN XI, XII
The phrenic nerves arise from the cervical plexus as anterior rami of _____. It’s function is _______
C3-C5
stimulate diaphragm for respiration
What are dermatomes?
Skin segments or areas ennervated by afferent fibers from one spinal nerve
Each dermatome overlaps with ________
two adjacent dermatomes
If three adjacent dermatomes are affected by three corresponding spinal cord injuries, it will result in
anesthesia
Paresthesia is __________
abnormal sensation along one or several dermatomes - pins, needles, numbness
Analgesia is ________
abolished or diminished pain sensation
A reflex is ________
inherent ability to briskly adjust body automatically to return body to homeostasis
The integrative center of cranial reflexes is _________
brainstem
The shoulder dermatomes are _______
C4-C6
The Thumb & Index finger dermatomes are ______
C6
The middle finger dermatomes are ______
C7
The ring and pinkie finger dermatomes are _______
C8
The nipple dermatomes is ________
T4
The umbilicus dermatome is ______________
T10
The knee dermatome is _________
L3
The ball of the foot, big toe dermatome is _________
L5
The foot sole dermatome is _________
S1
What are the componenets of a reflex arc?
sensory receptor of an organ/tissue sensory neuron integrative center motor neuron effector organ/tissue adjustment
The ansa cervicalis nerve arises from the cervical plexus as anterior rami of _____. Its function is _____
C1-C3
to stabilize hyoid bone, larynx during speaking and swallowing
The brachial plexus includes anterior rami of ______. Notable nerves arising from the brachial plexus include ________
C5-T1
musculocutaneous, axilary, radial, median, ulnar, long thoracic
The musculocutaneous nerve arises from anterior rami of _______. It ennervates _______ and controls _______
C5-C6
coracobrachialis, brachialis, biceps brachii
elbow flexion and supination
The axilary nerve arises from anterior rami of _______. It ennervates _______ and controls _______
C5-C6
Deltoid, teres minor
shoulder abduction
The radial nerve arises from anterior rami of _______. It ennervates _______ and controls _______
C5-T1
Extensors of the upper extremity
Extension in multiple joints
The median nerve arises from anterior rami of _______. It ennervates _______ and controls _______
C6-T1
forearm flexors except f. carpi ulnaris & lateral 1/2 of f. digitorum profundus, instrinsic thumb muscles, lateral 2 lumbricals
wrist and lateral finger flexion, wrist abduction, thumb movements
The ulnar nerve arises from anterior rami of _______. It ennervates _______ and controls _______
C7-T1
F. carpi ulnaris and medial 1/2 of f. digitorum profundus, medial 2 lumbricals
Wrist adduction/flexion, flexion of 2 medial fingers, abduction and adduction of 2nd-5th fingers
The long thoracic nerve arises from anterior rami of _______. It ennervates _______ and controls _______
C5-C7
serratus anterior muscle
upward rotation of the scapula
The accomodation reflex of the of eye is dependent upon which cranial nerves? Identify which is sensory and which is motor.
CN II - Optic - Sensory
CN III - Oculomotor - Motor
The pupillary light reflex of the eye is dependent upon which cranial nerves? Identify which is sensory and which is motor.
CN II - Optic - Sensory
CN III - Oculomotor - Motor
The corneal reflex requires sensory input via ______ and motor reaction as blinking via ______
CN V - Trigeminal
CN VII - Facial
