1. Autonomic Nervous System
Ch 14

2. The ANS and Visceral Sensory Neurons
Figure 15.1

3. Terms
Synapse – junction between 2 neurons that communicates the message from the presynaptic neuron to the postsynaptic neuron
Ganglion (pl. ganglia) – a cluster of neuronal cell bodies in the PNS
Preganglionic neuron – cell body lies within the CNS
- its axon, the preganglionic fiber synapses with the 2nd motor neuron, the ganglionic neuron, in a peripheral autonomic ganglion
Postganglionic fiber (axon) of the ganglionic neuron extends to the visceral organs

4. Anatomical Differences
Issue from different regions of the CNS
Sympathetic - aka the thoracolumbar division
Parasympathetic – aka the craniosacral division
Figure 15.3

5. Anatomical Differences
Length of postganglionic fibers: sympathetic are long and parasympathetic are short
Branching of axons: sympathetic axons are highly branched to influence many organs while parasympathetic axons have few branches so have a localized effect
Sympathetic release norepinephrine (adrenergic)
Parasympathetic release acetylcholine (cholinergic)

6. Comparison of Somatic & Autonomic Nervous System

7. Anatomical Differences
Figure 15.4a

8. Anatomical Differences
Figure 15.4b

9. Neurotransmitters Cholinergic fibers release the neurotransmitter ACh
All ANS preganglionic axons
All parasympathetic postganglionic axons
Adrenergic fibers release the neurotransmitter NE
Most sympathetic postganglionic axons
Exceptions: sympathetic postganglionic fibers secrete ACh at sweat glands and some blood vessels in skeletal muscles

10. Autonomic Nervous System
Parasympathetic and Sympathetic Nervous System:
A subdivision of the PNS
Not under conscious control
Controlled by medulla oblongata and hypothalamus
PNS supplies stimulation via motor nerves to smooth and cardiac muscle and to glands

11. Autonomic Nervous System
Biofeedback:
Conscious control of ANS
Ex. Yoga, meditation
Monitoring devices useful for:
epilepsy
digestive problems
chronic headaches
high blood pressure
generalized stress
anxiety
insomnia
The Beginnings of Biofeedback The word "biofeedback" was coined in the late 1960s to describe laboratory procedures then being used to train experimental research subjects to alter brain activity, blood pressure, heart rate, and other bodily functions that normally are not controlled voluntarily. At the time, many scientists looked forward to the day when biofeedback would give us a major degree of control over our bodies. They thought, for instance, that we might be able to "will" ourselves to be more creative by changing the patterns of our brainwaves. Some believed that biofeedback would one day make it possible to do away with drug treatments that often cause uncomfortable side effects in patients with high blood pressure and other serious conditions. Today, most scientists agree that such high hopes were not realistic. Research has demonstrated that biofeedback can help in the treatment of many diseases and painful conditions. It has shown that we have more control over so-called involuntary bodily fun ction than we once though possible. But it has also shown that nature limits the extent of such control. Scientists are now trying to determine just how much voluntary control we can exert. How is Biofeedback Used Today? Clinical biofeedback techniques that grew out of the early laboratory procedures are now widely used to treat an ever-lengthening list of conditions. These include:
·Migraine headaches, tension headaches, and many other types of pain
·Disorders of the digestive system
·High blood pressure and its opposite, low blood pressure
·Cardiac arrhythmias (abnormalities, sometimes dangerous, in the rhythm of the heartbeat)
·Raynaud's disease (a circulatory disorder that causes uncomfortably cold hands)
·Epilepsy
·Paralysis and other movement disorders
Specialists who provide biofeedback training range from psychiatrists and psychologists to dentists, internists, nurses, and physical therapists. Most rely on many other techniques in addition to biofeedback. Patients usually are taught some form of relaxation exercise. Some learn to identify the circumstances that trigger their symptoms. They may also be taught how to avoid or cope with these stressful events. Most are encouraged to change their habits, and some are trained in special techniques for gaining such self-control. Biofeedback is not magic. It cannot cure disease or by itself make a person healthy. It is a tool, one of many available to health care professionals. It reminds physicians that behavior, thoughts, and feelings profoundly influence physical health. And it helps both patients and doctors understand that they must work together as a team.

12. Autonomic Nervous System
Sympathetic
Parasympathetic
Work antagonistically
Myelinated motor neuron
Unmyelinated motor neuron
CNS
ganglion
effector
The output (motor) part of ANS has 2 principle branches sympathetic and parasympathetic
Ganglion- a collection of neuronal cell bodies outside the CNS

13. Neurotransmitter is norepinephrine “fight or flight”
Sympathetic Division
Neurotransmitter is norepinephrine
“fight or flight”
E = exercise, excitement, emergency, and embarrassment
The output (motor) part of ANS has 2 principle branches sympathetic and parasympathetic

14. Sympathetic Division Fight or flight adaptive effects include:
increased cardiac activity, increased blood pressure, dilation of skeletal muscle blood vessels
constriction of blood vessels in skin
dilation of pupil
inhibition of gut and urinary bladder contractions
increase in blood glucose and free fatty acid levels
dilation of bronchial smooth muscle  
secretion of viscous saliva
sweating
lower threshold for reticular formation activation
liver produces glucose to provide energy for muscle contraction.
The output (motor) part of ANS has 2 principle branches sympathetic and parasympathetic
Fight or flight adaptive effects include:
a) increased cardiac activity, increased blood pressure, dilation of skeletal muscle blood vessels - provides increased perfusion of vital organs and muscles
b) constriction of blood vessels in skin - limits bleeding from wounds
c) dilation of pupil - letting more light into the eye
d) inhibition of gut and urinary bladder contractions - inhibit defecation and urination
e) increase in blood glucose and free fatty acid levels - supply more energy
f) dilation of bronchial smooth muscle - easier flow of air
g) secretion of viscous saliva - possibly to avoid choking
h) sweating
i) lower threshold for reticular formation activation - reinforcing the alert state
j) liver produces glucose to provide energy for muscle contraction.

15. Parasympathetic Division
neurotransmitter is acetylcholine
D = digestion, defecation, diuresis (urinating)
Parasympathetic activation results in:
decreased cardiac activity
secretion of watery saliva and stimulation of GI secretions
contraction of urinary bladder
increased insulin and glucagon secretion
bronchiole constriction
The output (motor) part of ANS has 2 principle branches sympathetic and parasympathetic

16. Sympathetic Ganglia
Sites of synapses between pre and postsympathetic ganglia
sympathetic trunk ganglia
located from base of skull to coccyx
prevertebral ganglia
innervates organs below the diaphragm
The output (motor) part of ANS has 2 principle branches sympathetic and parasympathetic

17. Parasympathetic Ganglia
Site of synapses between pre and post parasympathetic ganglia
terminal ganglia
Located close to or within the wall of a visceral organ
The output (motor) part of ANS has 2 principle branches sympathetic and parasympathetic

18. Paradoxical fear when there is no escape route or no way to win
– causes massive activation of parasympathetic division
– loss of control over urination and defecation

19. Sympathetic

20. Parasympathetic

21. Parasympathetic Cranial Nerves
Oculomotor nerve
– ciliary ganglion in orbit
– ciliary muscle & pupillary constrictor muscle inside
eyeball
• Facial nerve
– pterygopalatine and submandibular ganglions
– supply tears, salivary & nasal secretions
• Glossopharyngeal
– otic ganglion supplies parotid salivary gland
• Vagus nerve
– many brs supply heart, pulmonary and GI tract as far as the midpoint of the colon

22. Autonomic Plexuses in the Thorax, Abdomen & Pelvis

23. Types of connections bwtn ganglia & postganglia neurons in the sympathetic division

24. Autonomic Reflexes Examples: Digestion Blood pressure Defecation
Urination
Components of an Autonomic Reflex:
Receptor
Sensory neuron
Integration center
Motor neuron
Effector (smooth or cardiac muscle, or a gland)

25. Hypothalamus & Medulla
Autonomic Control
Hypothalamus & Medulla
Major control and integration center of the ANS
Medulla oblongata

26. Inquiry
What neurotransmitter is produces from the Somatic nervous system, Sympathetic, and Parasympathetic nervous system?
What effector organs are targeted from the ANS?
Where does sensory input for the ANS come from?
List the components of an autonomic reflex arc.
What part of the brain is the major control and integration center of the ANS?
What effect does the parasympathetic nervous system have on the digestive system?
What effect does the sympathetic nervous system have on the liver?