1. The Peripheral Nervous System
Key Note:
The 12 pairs of cranial nerves are responsible for the special senses of smell, sight, and hearing/balance, and control movement of the eye, jaw, face, tongue, and muscles of the neck, back, and shoulders. They also provide sensation from the face, neck, and upper chest and autonomic innervation to thoracic and abdominopelvic organs.

2. The Cranial Nerves

3. The Peripheral Nervous System
The Spinal Nerves
_________
__________
12 Thoracic
___________
____________—Region of the body surface monitored by a pair of spinal nerves

4. The Peripheral Nervous System
Nerve Plexus—A complex, interwoven network of nerves
Four Large Plexuses
_____________

5. Cervical Plexus C1-C4 ventral rami Some fibers from C5
Innervates muscles of the ___________
______________
Phrenic nerve

6. Brachial Plexus Ventral rami of C5-T1
Innervates __________________________

7. Clinical Correlations
Erb-Duchene palsy
waiter’s tip position
fall on shoulder
Radial nerve injury
improper deltoid injection or tight cast
wrist drop
Median nerve injury
numb palm & fingers; inability to pronate & flex fingers
Ulnar nerve injury (clawhand)
inability to adduct/abduct fingers, atrophy of interosseus
Long thoracic nerve injury (winged scapula)
paralysis of serratus anterior, can’t abduct above horizontal

8. The Brachial Plexus

9. The Cervical and Brachial Plexus

10. Lumbar and Sacral Plexuses
____________- ventral rami of T12–L4
____________– ventral rami of L4–S4
Innervate pelvic girdle and lower limbs

11. The Lumbar and Sacral Plexuses,

13. The Autonomic Nervous System
Branch of nervous system that coordinates cardiovascular, ______________________, and reproductive functions
Should the lower text be 30 pt?

14. The Autonomic Nervous System
Divisions of the ANS
______________ division
neurons in the thoracic and lumbar segments of the spinal cord
“Fight or flight” system
___________________ division
neurons in the brain and sacral segments
“Rest and digest” system

15. The Autonomic Nervous System
Key Note:
The two divisions of the ANS operate largely without our awareness. The sympathetic division increases alertness, metabolic rate, and muscular abilities;
The parasympathetic division reduces metabolic rate and promotes visceral activities such as digestion.

16. The Sympathetic Division

17. The Autonomic Nervous System
Effects of ___________ Activation
Generalized response in crises
______________________
Feeling of euphoria and energy
Increased cardiovascular activity
__________________________
Increased muscle tone

18. The Parasympathetic Division

19. The Autonomic Nervous System
Effects of _____sympathetic Activation
Relaxation
_________________
Brief effects at specific sites

20. The Autonomic Nervous System
Relationship between the Two Divisions:
Sympathetic division reaches visceral and somatic structures throughout the body
Parasympathetic division reaches only visceral structures via cranial nerves or in the abdominopelvic cavity
_________________________________
In general, the two divisions produce opposite effects on the their target organs

21. The Peripheral Nervous System
Key Note:
Reflexes are rapid, automatic responses to stimuli that “buy time” for the planning and execution of more complex responses that are often consciously directed.

22. The Peripheral Nervous System
Reflex—An automatic involuntary motor response to a specific stimulus
The 5 steps in a reflex arc
Arrival of stimulus and activation of receptor
___________________________
CNS processing of information
Response by effector (_______________)

23. Reflex Action Sensation relayed to the brain by collateral Dorsal root
Arrival of
stimulus and
activation of
receptor
Activation of a
sensory neuron
REFLEX
ARC
Receptor
Stimulus
Effector
Ventral
root
Information
processing
in CNS
Response
by effector
Activation of a
motor neuron
KEY
Sensory neuron
(stimulated)
Excitatory
interneuron
Reflex Action
Motor neuron
(stimulated)

24. Stretching of muscle tendon stimulates muscle spindles Muscle spindle
(stretch receptor)
Stretch
Spinal
cord
REFLEX
ARC
Contraction
Activation of motor
neuron produces reflex
muscle contraction
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25. The Flexor Reflex

26. Aging and the Nervous System
Age-Related Changes
Reduction in brain size and weight
_______________
______________________
Changes in synaptic organization of the brain
Intracellular and extracellular changes in CNS neurons