1. Neuromuscular Control of Movement

2. Organization of Brain Motor Centers

3. The -Motor Neuron Innervates skeletal muscle
Receives input from higher centers
Receives sensory input from muscle stretch and tension receptors

4. Motor Unit
Schwann cells, cell body, dentrites, “splintering,” nodes of ranvier, integrate signals from above and below, axon hillock, myelin sheets

5. The -Motor Neuron All or none Size principle
Once you reach threshold an action potential is initiated. EPSP/IPSP
Size principle

6. Motor Unit

7. Motor Unit

8. Motor Unit
The ratio of nerves to muscle fiber is specific to a motor unit and defined by the task.
Fine movements (focusing eyes)
Gross movements (muscles involved in jumping)

9. Motor Unit

10. Motor Unit

11. Muscle Recruitment
Training
In the lab!

12. Motor Unit Stim Freq Large Motor Unit, Brief Contraction Time
Small Motor Unit,
Long Contraction
Time
Motor units with brief contraction times (larger units) require a higher stimulating frequency to produce tetanus than do smaller slow-twitch units. In Fig-13 a large and small motor unit from the gastrocnemius of the cat were stimulated repeatedly at 5, 10, 20,50, and 100 stimuli per second. Notice that the large unit in column A showed little tetanus until the frequency reached 20 per second and didn't develop maximum tension until the frequency reached 100 per second. By comparison, the small motor unit in column B began to tetanize at the relatively low frequency of 10 per second and was nearly maximal at 20 per second. Column C shows the response of a soleus motor unit similar in size to the small gastrocnemius motor unit in column B. Remember that most of the motor units in the gastrocnemius muscle have shorter contraction times than most of the soleus units. It is not surprising to find that the average frequency required for tetanization of the gastrocnemius motor units is greater than we find in the soleus motor units.

13. Neuromuscular Junction

14. Neurodengerative disorder. David Rabin. Steven Hawking. Jason Becker

15. Muscle Sensors
Allow for fine control and adjustments of muscle movements.
Protect musculoskeletal system from injury.

16. Fine Control of Motor Movements

17. Muscle Spindle

18. Golgi Tendon Organ

19. Chemical Feedback
Control of Breathing

20. “Muscle Memory”

21. “Muscle Memory”

22. “Muscle Memory”

23. “Muscle Memory” is a form of Neural Memory

24. Spinal Cord Autonomy

25. Nerve determines Muscle Characteristics

26. Nerve determines Muscle CharacteristicsF S F Sc Fc
mitochondrial  -glycerolphosphate-dehydrogenase

27. Nerve determines Muscle Characteristics
Stimulation Frequency
Soleus by FDL Nerve S F S F
Soleus by Soleus Nerve Sc Fc
FDL by Soleus Nerve
FDL by FDL Nerve
mitochondrial  -glycerolphosphate-dehydrogenase

28. Training the Motor Unit?