1. Peripheral & Autonomic Nervous System
Chapter 9

2. Peripheral Nervous System
Page 169
Peripheral Nervous System
All the nerves that connect the brain & spinal cord with sensory receptors, muscles, & glands
Afferent peripheral system – conveys information from the periphery to the brain & spinal cord
Efferent peripheral system – conveys information from the brain & spinal cord to the muscles & glands
Somatic – from brain & spinal cord to skeletal muscle
Autonomic – from brain & spinal cord to smooth muscle

3. Efferent Peripheral System
Page 169
Efferent Peripheral System
Somatic nervous system – Responds to changes in the external environment
Autonomic nervous system
Sympathetic : fight or flight response (norepinephrine)
Parasympathetic: rest and digest response (acetylcholine)

4. Pages 169 – 170
Nerves
Bundles of nerve fibers enclosed by connective tissue
Sensory (afferent) nerves
Motor (efferent) nerves
Mixed nerves
Sensory or afferent nerves – carry impulses from the sense organs to the brain or spinal cord
Motor or efferent nerves – carry impulses from the the brain or spinal cord to muscles or glands
Mixed nerves – if the bundle contains both sensory & motor fibers

5. Cranial & Spinal Nerves
Page ?
Cranial & Spinal Nerves
Part of the peripheral nervous system
12 pairs of cranial nerves
Originate from the brain & brain stem
31 pairs of spinal nerves
Direct connection to the spinal cord
Plexus
Largest spinal nerve: sciatic

6. Cranial Nerves Page 171 I Olfactory Smell II Optic Vision III
Oculomotor
Eyelid & eyeball movement IV
Trochlear
Innervate superior oblique muscle, turns eye downward & laterally V
Trigeminal
Sensation of face & mouth espcially chewing VI
Abducens
Turns eye laterally
VII
Facial
Taste & controls most facial expressions, secretion of tears & saliva

7. Cranial Nerves (Cont’d)
Page 171
Cranial Nerves (Cont’d)
VIII
Vestibulocochlear
Hearing & equilibrium IX
Glossopharyngeal
Taste & controls swallowing, secretion of saliva X
Vagus
Sensation from the larynx, pharynx, liver, stomach & movement in organs of the thoracic & abdominal area XI
Spinal accessory
Controls trapezius & sternocleidomastoid muscles
XII
Hypoglossal
Movement of tongue muscles

8. Spinal Nerve Plexus Page 170 Cervical plexus Brachial plexus
Lumbar plexus
Sacral plexus

9. Autonomic Nervous System
Page 172
Autonomic Nervous System
Nerves, ganglia, & plexuses that carry impulses to all smooth muscle, secretory glands, & heart muscle
Sympathetic system – accelerate the heartbeat in response to fear
Parasympathetic system – slows the heartbeat down
Strongly influenced by emotion
They are antagonistic to each other

10. Sympathetic System Page 172
Fight-or-flight system – meant for acute stress, not chronic stress
Consists primarily of two cords, beginning at the base of the brain and proceeding down both sides of the spinal column
Nerves extend to all vital organs
Learning to cope with stress is essential to preventing overstimulation of this system & the subsequent problems

11. Parasympathetic System
Pages 172 – 175
Parasympathetic System
Two important active nerves: Vagus & Pelvic nerves
Counteracts effects of the sympathetic nervous system
Brings the body back to homeostasis

12. Reflex Arc Page 175 Simplest type of nervous response
It is unconscious & involuntary
Every reflex act is preceded by a Stimulus
Receptors = special structures that pick up stimuli
Response = reaction to stimulus
Stimulus = change in the environment

13. Page 175
Biofeedback
Measurement of physiological responses that yields information about the relationships between the mind & the body & helps people learn to manipulate those responses through mental activity
Enhances relaxation
the use of electronic monitoring of a normally automatic bodily function in order to train someone to acquire voluntary control of that function.

14. Pages 175 – 176
Disorders
Neuritis – inflammation of a nerve. Symptoms may be severe pain, hypersensitivity, loss of sensation, muscular atrophy, weakness, & paresthesia.
Sciatica – a form of neuritis that affects the sciatic nerve. Symptom is pain that radiates through the buttocks & behind the knee down to the foot.
Peripheral neuropathy – damage to the peripheral nerves. Most commonly caused by diabetes.
Neuralgia – sudden, severe, sharp, stabbing pain along the pathway of a nerve.
Neuritis – The causes of neuritis may be infectious, chemical, or due to other conditions such as chronic alcoholism. In the patient who is diagnosed with alcoholism, neuritis usually occurs because of a lack of vitamin B or an improper diet.
paresthesia (tingling, burning, & crawling of the skin)
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15. Disorders (Cont’d) Page 176
Trigeminal neuralgia – cause is unknown, onset is rapid, pain is severe. (fifth cranial nerve
Bell’s palsy – condition that involves the seventh cranial nerve. Patient appears as if they have had a stroke.
Shingles or herpes zoster – acute viral nerve infection. Characterized by a unilateral inflammation of a cutaneous nerve.
Carpal tunnel syndrome – a condition that affects the median nerve & the flexor tendons that attach to the bones of the wrist.

16. Types of Anesthesia Page 177 SB Local numbing of area
Regional anesthesia
Spinal anesthesia
Epidural anesthesia
General anesthesia