Somatic Motor System module

1. Somatic Motor System module (next slide)

2. Somatic Motor menu Somatic Motor system Overview of the Somatic Motor system Praxis Clinical signs related to the Somatic Motor system Select a blue button to move to that topic (previous slide) (next slide) (select this button to return to this slide)

3. Somatic Motor system Overview of the Somatic Motor system Praxis Clinical signs related to the Somatic Motor system (next)

4. overview Somatic Motor System • Interactions of the sensory and motor systems enable voluntary movement • You have learned about these sensory and motor pathways earlier in this class!

6. Somatic Motor System Internal motor systems (cerebellum & basal ganglia) must be effective for functional motor output to take place. Exit circuitry (motor output pathways) also must be effective for functional motor output.

7. Exit circuitry: Corticoreticulospinal & Vestibulospinal pathways - control of trunk muscles; posture corticoreticulospinal & vestibulospinal

8. Exit circuitry: Corticospinal pathway - finely tuned hand movements corticospinal

9. Exit circuitry: Corticorubrospinal pathway - limb movements corticorubrospinal

10. corticobulbar • Exit circuitry: • Corticobulbar • pathway • finely tuned movements of the face & head Somatic Motor menu

11. Somatic Motor system Overview of the Somatic Motor system Praxis Clinical signs related to the Somatic Motor system (next)

12. praxis Praxis • The ability to produce a NEW motor response • Describes earlier phases of the motor learning process, NOT the execution of a learned or practiced motor pattern • Once a motor act is practiced & learned, it NO LONGER requires praxis!

13. Praxis • Depends upon multisensory input

14. Praxis • Depends upon multisensory inputs • Allows multiadaptive responses in context Somatic Motor menu

15. Somatic Motor system Overview of the Somatic Motor system Praxis Clinical signs related to the Somatic Motor system (next)

16. Somatic Motor Clinical signs Position sense test Clonus Babinski sign Enhanced deep tendon responses Spasticity Clasp knife response Select buttons to view videoclips 1 2 3 4 5 6 Clinical Signs Signs

17. Position sense Play Movie With the client’s eyes closed, the clinician manipulates the client’s right thumb. He is asked to point his left thumb in the same direction as his right thumb. The clinician switches sides and he is no longer able to perform the task. Clinical Signs Signs

18. Clonus Play Movie A series of fast, involuntary contractions symptomatic of damage to upper motor neurons. Clinical Signs Signs

19. Babinski reflex Play Movie An extension of the great toe, sometimes with fanning of the other toes, in response to stroking of the sole of the foot. It is a normal reflex in infants, but it is usually associated with a disturbance of the pyramidal tract in children and adults. Clinical Signs Signs

20. Enhanced Deep Tendon Reflexes Play Movie An unusually vigorous patellar tendon reflex may be observed following upper motor neuron damage, often in conjunction with heightened muscle tone (spasticity) and clonus. Clinical Signs Signs

21. Spasticity Play Movie The man exhibits spasticity of the right side, while the woman exhibits spasticity of the left side. Note the posture of the affected arm, the swinging of the leg from the hip with reduced range of the knee and ankle joints, and the reduced dynamic balance. Clinical Signs Signs

22. Clasp knife response Play Movie An animation of the concept, meant to illustrate an initially great resistance to extension of the joint, followed by a gradual “melting” of the resistance as continued, steady pressure is applied. Clinical Signs Signs

23. That ends the Somatic Motor system tutorial! Somatic Motor menu