Reflexes Flashcards
Definition
Involuntary motor response, almost instanteneus, to a specific stimuli
Myotatic reflex sensory propioreceptor
Muscle spindle
Golgi tendon senses
Excessive stretching
Inverse myotatic reflex sensory propioreceptor
Golgi tendon organ
Muscle spindle senses
Muscles fibers stretched
First motor neuron disease - reflex is…
Exacerbated
Second motor neuron disease - reflex is …
Abolished
Bicipital reflex occurs at
C5-C6
Effect of bicipital reflex
Subtle arm flexion
Supinator / estiloradial reflex occurs at…
C5-C6
Effect of supinator reflex
Wrist flexion
Tricipital reflex occurs at
C6-C7
Effect of tricipital reflex
Subtle arm extension
Patellar reflex occurs at
L3, L4
Effect of patellar reflex
Extension of the leg
Achilles tendon reflex occurs at
L5-S1
Effect of Aquiles tendon reflex
Plantarflexion
Cutaneous reflexes
Withdrawal reflex
Cutaneous-abdominal reflex
Cremasteric reflex
Cutaneous-plantar reflex
Effect of cutaneous plantar reflex
Flexion of all the toes
Physiological in newborns but pathological in adults
Effect of cremasteric reflex
Elicited when the inner part of the thigh is stroked. Stroking of the skin causes the cremaster muscle to contract and pull up the ipsilateral testicle toward the inguinal canal
Cortico-bulbar reflexes
Pupillary reflex
Menace reflex
Glabelar reflex
Mandibular reflex
Corneal reflex
Snout reflex
Oculovestibular reflex
Startle reflex
Cough reflex
Gag / vomiting reflex
Pupilar, glabelar reflexes - nerves involved
CN II (optic) - senses the light
CN III (oculomotor) - dilates/contracts the pupil
Mandibular reflex - nerves involved
CN V (trigeminal) - sensory and motor
Only myotatic reflex in the cranial-nerve system
Corneal, snout reflexes - nerves involved
Blink reflex
CN V (trigeminal) - afferent fiber
CN VII (facial) - efferent fiber
Cough, vomit reflexes - nerves involved
Vomiting
CN IX (glossopharingeal) - senses stimuli
CN X (vagus) - response
How many neurons do we need for a reflex?
2
Osteotendinous reflexes
Myotatic reflex
Myotatic inverse reflex
Contralateral extensor reflex
Contralateral extensor reflex
Situation: we are walking and step on something which hurts. We withdraw the limb with the stimulus, but the other limb has to make strong contraction with the extensor muscles, in order to keep balance = contralateral extensor reflex.
Myotatic reflex is
Monosynaptic
Myotatic inverse reflex is
Polisynaptic
Startle reflex - nerves involved
CN VIII (vestibulocochlear)
Other reflexes
Palmar - mental reflex
Grasping reflex (palmar grasp) - babies
Suction reflex - babies
Cremasteric effect occurs at
L1-L2
Cutaneous plantar reflex occurs at
S1-S2
