Question | Answer |
What is autonomous? | outside of our voluntary conscious control |
What is semi-autonomous? | have both conscious and involuntary components |
What are the motor targets for PNS and ANS? | skeletal muscle |
What is the autonomic targets for PNS and ANS? | smooth muscle, cardiac muscle, and glands |
Explain motor portions of efferent pathway: | has no ganglia, one myelinated axon to target |
Explain autonomic portion of efferent pathway: | 2 neuron pathway, neuron1 = preganglionic with soma in CNS, Neuron 2= postganglionic with soma in autonomic ganglion |
Which ganglionics are myelinated and unmyelinated? | preganglionics = myelinated, postganglionics = unmyelinated |
What does the autonomic nervous system innervate? | smooth muscle, cardiac muscle, glands, visceral organs |
What is the autonomic nervous system regulated by? | higher brain structures |
What is the principle organizing center for ANS activity? | hypothalamus |
What does the axons that connect the hypothalamus to the autonomic nuclei and gray matter? | dorsal longitudinal fasciculus (DLF) |
Where does the axons of the DLF synapse? | parasympathetic nuclei of CN 3,7,9,10 , intermediolateral cell column of spinal cord, sacral autonomic cells of spinal cord |
How do autonomics innervate their targets? | indirectly by a 2 neuron chain |
Where is the cell body and axon of Neuron 1 of ANS located? | cell body in CNS axon terminates in cell body of neuron 2 |
Where is the cell body and axon of neuron 2 in the ANS? | cell body outside CNS in PNS, axon terminates on target organ |
What are the two primary divisions of ANS and what are their function? | sympathetic= fight or flight, parasympathetic= rest and digest |
What are the neurotransmitters of sympathetic system? | preganglionic=acetylcholine, postganglionic=norepinephrine |
What are the neurotransmitters of PNS? | pre and post ganglionic= acetylcholine |
Where are preganglionic neurons located in PNS? | CN3,7,9,10 ,spinal cord, sacral 2-4 |
Where are preganglionic neurons are located for SNS? | T1-L2 |
Where are the SNS preganglionic neuron somata located? | intermediolateral cell column in thoracic and upper 2 lumbar segments of spinal cord |
Where do the SNS preganglionic axons exit spinal cord and how do they travel? | thoracic and lumbar nerves, from spinal nerves to sympathetic chain via white ramus |
Do all SNS preganglionics synapse in the sympathetic chain? | No some passout of the chain to synapse on their target |
What happens after axons from sympathetic chain exit ganglia? | rejoin spinal nerves via grey ramus |
What are the sympathetic postganglionic neurons located? | sympathetic chain, ganglia in abdomen (celiac, superior mesenteric, inferior mesenteric), adrenal medulla |
Explain the character of preganglionic fibers: | generally short, postganglionic neurons located away from target organ |
What does activation of the SNS cause? | fight or flight (increased HR, decreased peristalsis, increased BP, dilation of coronary arteries, dilation of bronchioles, shunting of blood from gut to skeletal muscle, dilation of pupils |
What would cause a systemic response? | pain, strong emotion like rage or fear |
Where are the preganglionic neurons of the PNS located? | CN nuclei 3,7,9,10 , and sacral segements 2-4, this compilation is known as cranial sacral outflow |
What is the character of parasympathetic preganglionic and post ganglionic fibers? | generally long preganglionics with posteriorganglionics near the target organ so they are short |
What does the activation of PNS cause? | rest and digest (decreased CO, decreased BP, increased peristalsis, contraction of bladder, papillary constriction |
Are C fibers myelinated or unmyelinated? | unmyelinated |
Which side of the brain is Wernike’s area? | almost always on the left |