Exam Two Study Guide:
1. Proprioception is: ______________________________________. 2. The three proprioceptors that we have learned about are: ________,
________, & _______.
3. Role of proprioception in motor control: _______, ________, & _________. 4. Deafferentation is essentially means: _________________. 5. Muscle spindles are located: _______________________________ 6. Muscle spindles function to: _____________________
7. The sensory fibers that innervate muscle spindle fibers are: ________ &
8. * The stretch reflex steps one through four are:
________________________________________________________________________ 9. Golgi-Tendon Organs are located: _________________
10. Golgi-Tendon Organs function to: _________________ 11. The sensory fibers that innervate GTO’s are:
12. Tendon Reflex sequence:
________________________________________________________________________ 13. Joint receptors are generally located: __________________________ 14. Joint receptors function to: __________________________ 15. Visceral pain is: ____________________
16. Name the two types of pain & their receptors:
17. Withdraw Reflex/Crossed Extensor Reflex sequences: ________________________________________________________________________
We also discuss several other topics like What are the differences between public health and medicine?
________________________________________________________________________If you want to learn more check out What is the content of the civil rights act of 1875?
18. Define presynaptic inhibition & presynaptic facilitation: ________________________________________________________________________
________________________________________________________________________ 19. Define ESPS & IPSP:
________________________________________________________________________ 20. How do you calculate summation (net facilitation) of neural input
on specific neuron?
________________________________________________________________________ 21. Gamma motor neurons are located: _____________________ Gamma motor neurons function to: _____________________ 22. Explain alpha gamma co activation:
________________________________________________________________________ 23. Explain Renshaw cells: We also discuss several other topics like What are the two phases of glycolysis?
________________________________________________________________________ 24. Explain the Hoffman Reflex:
________________________________________________________________________ We also discuss several other topics like What is the definition of alcohol poisoning?
________________________________________________________________________ 25. Provide the general symptom for each specific spinal lesion We also discuss several other topics like What is the definition of the pyramidal hierarchical model?
provided: C5 (deltoid & biceps), C7 (triceps, extensors of wrist and fingers), L2-4 (quadriceps), and S1 (plantarflexors & gastrocnemius)
1. The ability to feel and sense the position & movements that we make with our limbs, trunk, and head - the information involves the direction
and velocity as well as the location in space & muscle activation 2. Muscle spindles, Golgi-Tendon Organs, and Joint Receptors/Pain 3. Accuracy of movement, onset of motor commands, completing
coordinated control of movement
4. To destroy or cut off an afferent pathway in the body 5. In the deeper belly in the body of muscle, between extrafusal muscle
6. Detect a change in the length or the rate of change in the length of the muscle (velocity), also enables the detection of changes in the angle of the jointDon't forget about the age old question of How are italian and northern art styles different?
7. Group la axon & group ll axon (transmit length info to CNS) 8. 1. Muscle spindle detects muscle stretch – hammer tap
2. sensory neurons conduct action potentials to spinal cord 3. sensory neurons synapse directly with alpha motor neurons 4. alpha motor neurons conduct action potential to muscle & cause it to contract/resist being stretched
9. in skeletal muscles near the insertion of a tendon / between muscle
fibers and tendon
10. Detect the changes that occur in muscle tension (ex: force) 11. A single lb axon that intertwines among braided collagen fibers 12. Muscle tension increases -> GTO stretch -> lb fibers activated ->
inhibitory interneuron excited -> alpha-motoneurons inhibited -> muscle relaxes -> excitation of Golgi tendon organs from a muscle =
reduced excitation of muscle
13. In the joint capsule/ligaments
14. Detect changes in joint movement at extreme limits of
movement and position
15. Poorly localized & commonly expressed as referred pain in which
the pain is referred to a somatic structure (heart attacks) 16. Short-latency pricking pain evoked by noxious stimuli that is
carried by Alpha gamma fibers/group III afferents. Long-latency pain of
burning and less bearable quality carried by C-fibers/group IV afferents 17.
a. Withdrawal: activation of pain fibers (flexor reflex afferents) – excite excitatory interneurons that innervate flexor alpha motoneurons and inhibitory innervating extensory alpha motoneurons = flexion (withdrawal from stimulus) = pain fibers
ultimately excite flexor muscles and inhibit extensor muscles to
permit the withdrawal response
b. Crossed Extensor reflex: on opposite side of flexion response – activation of pain fibers (flexor reflex afferents) -> excitation of excitatory interneurons that innervate extensor alpha
motoneurons and inhibitory interneurons that innervate flexor alpha motoneurons = extension on opposite side of flexion
(evident when stepping on something sharp)
18. Presynaptic inhibition: when one neuron suppresses another Presynaptic facilitation: when one neuron facilitates another 19. EPSP: postsynaptic potential that makes post synaptic neuron
more likely to fire an action potential
IPSP: postsynaptic potential that makes post synaptic neuron less likely to fire an action potential
20. The process that determines whether an action potential will be triggered by combined effects of excitatory and inhibitory signals (both from multiple simultaneous inputs (spatial summation) and from
repeated inputs (temporal summation))
21. Location: anterior horn of spinal cord
Function: keep muscle spindles taut and adjust sensitivity of muscle
22. When alpha motoneurons and gamma motoneurons are activated at the same time. Allows spindle to act as error detection system (CNS is informed about length of muscle compared to what CNS initially intended) – adjustments made by CNS to achieve desired length
23. Inhibitory interneurons that are found in gray matter of spinal cord & associated with alpha motoneurons. They receive input from brain. They are excited by collaterals from motor neurons, and then inhibit those same motor neurons. Regulates motorneuron excitability
& descending inputs that modulate excitability of Renshaw cell adjust
excitability of motor neurons associated with that specific Renshaw cell 24. An electric analog for the tendon jerk reflex based on Paul
Hoffman’s work in 1910, introduced in the 1950’s. It examines the characteristics of the monosynaptic connections from la sensory fibers to spinal neurons in humans. Electrically stimulating la fibers in the
peripheral nerve to record reflex response in homonymous muscle a. An estimation of net spinal excitability
b. La fibers of plantarflexors excited by electrode placed behind knee over tibial nerve – response is recorded with EMG
depending on stimulus strength
25. - C5: reflexes of the biceps are lost
- C7: reflexes of triceps are lost
- L2-4: knee-jerk reflexes are lost (knee will not respond to knee-jerk
- S1: ankle jerk reflexes are lost