Autonomic Nervous System Flashcards
Name three processes that the autonomic nervous system are continuously regulating
Thermoregulation
Cardiovascular function
GI function
**Only some examples
Where are the ganglion located in sympathetics? Parasympathetics?
Sympathetics - Ganglia close to vertebrae
Parasympathetics - Ganglia close to target organ
Why are autonomics organized in two neuron arcs?
This allows considerable divergence of signal so that many targets can be activated at once
Where do parasympathetics exit the CNS? Sympathetics?
Parasympathetics - Craniosacral levels
Sympathetics - Thoracolumbar levels
What is the asymmetry between sympathetic and parasympathetic innervation?
Sympathetics innervate skin and peripheral blood vessels, parasympathetics do not
*Parasympathetics do not go to the body wall
What structures in the skin are notably only innervated by sympathetics?
Sweat glands
Arrector pilae muscles
What structure controls thermoregulation?
Hypothalamus
What is the body’s response to increased temperature?
Peripheral Vasodilation
Increased sweating
Water and electrolyte retention
What is the body’s response to decreased temperature?
Peripheral vasoconstriction
Decreased sweating
Contract arrector pilae muscles
Shivering
What is the name for the sympathetic ganglia that travel along side the spine?
Paravertebral Ganglia
What are splanchnic nerves?
Nerves through which preganglionic axons of the sympathetic system leave the paravertebral chain and synapse onto the pre-aortic ganglia
What are the two pathways that sympathetics get to the skin?
Exit spinal cord in thorax and synapse in the ganglion at that level
Exit in thora and ascend or descend chain of ganglia
What is Horner’s Syndrome?
Damage to sympathetic pathways
Miosis - pupillary constriction
Ptosis - Drooping eyelid
Anhydrosis - lack of sweating
Why does damaging the sympathetic system cause ptosis?
Levator palpebrae superioris muscle takes its origin from the tendinous ring
The tendinous ring is composed of, in part, smooth muscle controlled by sympathetics
How can you differentiate between horner’s syndrome and damage to the oculomotor nerve?
Oculomotor damage will dilate the pupil and also present with eye movement abnormalities
It will also not effect sweat glands
