Lecture 75 - Autonomic Nervous System

Question 1

There are 4 Parasypathetic nuclei in the Brainstem.

1. Occulomotor and ______ ______ nucleus (CN III)
2. Superior ________(CN VII)
3. Inferior _______ (CN IX)
4. Dorsal Motor Nucleus (CN ___)

Answer 1

1. Occulomotor and Edinger Westphal nucleus (CN III)
2. Superior Salivatory (CN IV)
3. Inferior Salivatory (CN IX)
4. Dorsal Motor Nucleus (CN X)

Question 2

Autonomic aspect of CN III synapses on the ______ ganglion.

Autonomic aspect of CN VII synapses on the ______ and _____ ganglia.

Autonomic aspect of CN IX

Answer 2

Cilliary

Submandibular

Otic

Question 3

The preganglionic neurons in the Parasympathetic nervous system are _______ (myelinated or unmyelinated?), while the postganglionic are ________ (myelinated or unmyelinated?).

Answer 3

Myelinated

Unmyelinated

Question 4

THe Sympathetic nervous system has the following composition/pathway system:

Preganglionic neurons begin in the ________ of the spinal cord and exit the spinal cord via the _______ horn –> they enter the Prevertebral ganglia OR the _________ ganglia via the white ramus (think about why it might be white) or –> synapse with postganglionic neurons –> postganglionic neurons exit the ganglia via the gray ramus (think about why it might be gray).

Answer 4

IML

Ventral horn

Paravertebral ganglia

White ramus is white bc preganglionic neurons are myelinated

Gray ramus is gray bc postganglionic neurons are unmyelinated.

Question 5

Remember that ________ muscle and ______ do NOT have Parasympathetic innervation.

Answer 5

Skeletal muscle

Skin

Question 6

Sympathetic nervous system Cervical ganglia and their functions:

Superior –> SNS aspects of _____ and _____ + ______ plexes.

Middle –> _____ + ______ plexes

Stellate (C8 + T1) –> ______ + ______ plexes and Arm vessels

Answer 6

Face and Cardiac + Pulm plexes

Cardiac + Pulm plexes

Cardiac + Pulm plexes

Question 7

Afferent signals to the Sympathetic nervous system (SNS) come in through cell bodies in the DRG at the ___-___ levels.

Afferent singals to the PNS come in through different ganglia:

Taste from the anterior 2/3 of the tongue, conveyed by CN VII, comes into the ______ ganglion. Taste from the posterior 1/3 of the tongue, conveyed by CN IX, comes into the Inferior _______ ganglion. Afferents from the thoracic and abdominal viscera, conveyed by CN X, come into the ______ ganglion. Afferents from the Pelvic viscera come into the ______ DRG.

Answer 7

T1-T12 levels

Geniculate

Inferior Petrosal

Nodose

Sacral DRG

Question 8

Horner’s syndrome is a triad of symptoms that arise from a lesion in the _______ (sympathetic or parasympathetic pathway?) that innervates the face. It results in which three key symptoms?

Answer 8

Sympathetic

1. Miosis (radial muscle of the eye knocked out –> pupil constricts due to unopposed parasympathetic tone of the Circular muscle)
2. Ptosis (tarsal muscle of the upper eyelid knocked out)
3. Anhydrosis (ONLY sympathetic innervation in sweat glands, so when that’s knocked out, no sweat)

Question 9

When a person stands from sitting and their BP drops –> it’s detected by Barroreceptors in the ______ sinus –> sends signal to the ______ nucleus in the pons and medulla –> sends signals to the _______ –> sends signal to sympathetics in the IML of the spinal cord –> vasoconstriction and increased cardiac contraction/heart rate.

Keep in mind the RVLM also signals to the Vagus to counterbalance the above effect and prevent overcompensation.

Answer 9

Carotid sinus

Solitary nucleus

RVLM (Rostral Ventrolateral Medulla)

Question 10

The ______ center in the Pons is what controls the bladder response to filling.

Answer 10

Micturition center