The Reflex

Question 1

Why is the reflex important?

Answer 1

1. understand normal physiology
2. understand how neurologic diseases present
3. understand how to perform and interpret a neurologic exam

Question 2

Reflex Arc Components

Answer 2

1. sensory receptor
2. sensory neuron
3. synapse
4. motor nueron
5. target organ

Question 3

Synapse

Answer 3

connection between incoming sensory neuron and 2nd neuron

Question 4

Sensory Receptor

Answer 4

translates stimulus into action potential. Ex: muscle stretch, pain, light

Question 5

Sensory Neuron

Answer 5

carries action potential from receptor to CNS

Question 6

Motor Neuron

Answer 6

carries action potential from CNS to effector organ

Question 7

Patellar Reflex

Answer 7

tap patellar tendon to stretch quadriceps to cause quadriceps to contract and extend the stifle. If there is a problem in reflex arc there won’t be a reflex

Question 8

Withdrawal Reflex

Answer 8

flex leg when pinch skin between toes. Sensory receptors are superficial pain receptors in skin, go up sensory neuron, through dorsal root ganglion, through inner neurons, synapse on motor neuron, exit ventral root, go to multiple muscles to flex hip, stifle, and hock. Problem in either L6-S1 spinal cord.

Question 9

Segmental Reflex

Answer 9

goes into nervous system and comes out at same level. Only involving small segment of CNS

Question 10

Intersegmental Reflex

Answer 10

Goes in one area, travel far back in nervous system, and then back out

Question 11

Proprioception

Answer 11

sense of where your body is in space

Question 12

Proprioceptive Positioning

Answer 12

sensory axon go up through spinal cord, back part of brain, brain stem, up to cerebrum. Brain recognizes foot in abnormal position, goes through inner neurons to motor neuron, down spinal cord, synapse motor neuron back down several nerves to muscles that correct foot into normal position

Question 13

Ataxia

Answer 13

caused by loss of proprioception