Lab #11: Spinal Cord, Spinal Nerves and Cranial Nerves

You enter a patient's room and find them on the floor unconscious. You immediately shine a light into their eyes and tell your colleague, "Their pupils are fixed and dilated." Which of the following statements is most likely to be true?

This isn't good. CN III (oculomotor) has been affected in some way.

Which nerve is being tested by asking the patient when they can hear the rubbing sounds?

VIII - vestibulocochlear

Which cranial nerve can be assessed by asking the patient to smell a cotton swab that contains vanilla extract?

CN I - olfactory

A patient is suffering from the inability to distinguish various types of odors. This patient may have damage to which of the following?

CN I - olfactory nerve

Dr. Jaworski explained in her video that one of the cranial nerves can't be seen on the inferior surface of the brain or brainstem. However, she did explain that the axons from the cranial nerve do synapse on a structure that we can see on the inferior surface of the brain. What is the cranial nerve, and what is the structure that we can see on the inferior surface of the brain?

CN I - olfactory nerve; olfactory bulb

This purely sensory cranial nerve carries signals associated with vision.

CN II - optic

Damage to which nerve causes blindness?

CN II - optic nerve

Which cranial nerve collects visual images from the eye?

CN II - optic nerve

Which cranial nerve can be tested by shining a light into the patient's eyes to test pupillary constriction?

CN III - oculomotor

Which cranial nerve or nerves is/ are tested by drawing an "H" in the air with your finger, and asking the patient to follow your finger with their eyes?

CN III, IV, and VI

Which cranial nerve can be tested by asking the patient to clench their jaw tight by contacting their master muscle?

CN V

Which of the following cranial nerves carries only motor information?

CN VI - abducens

As a cook chops red onions he begins to tear up due to activation of the lacrimal gland. Which of the following nerves provided the stimulus?

CN VII - facial nerve

Dr. Davies described that 3 cranial nerves have a role in swallowing. What are these nerves?

IX, X, and XI

Which statement is TRUE about the hypoglossal nerve?

If it is damaged, the patient's tongue will deviate toward the side of the lesion.

The cell bodies of sensory neurons are located inside... (#11)

B, dorsal root ganglion

Why is the spinal cord shorter than the vertebral column in an adult human?

Because the bones of the skeleton, and therefore the vertebral column continue to grow long after the spinal cord has reached its full length.

Bell's Palsy is a condition in which a patient has paralysis or weakness of the muscles on one side of their face. Typical symptoms include drooping of the lower eyelid, one side of the mouth is turned down, inability to close the eye on one side, possible drooling or excessive tear production and loss of taste. In most cases, Bell's Palsy is thought to be caused by a virus that affects one of the cranial nerves, and not by a stroke or TIA (transient ischemic attack). Which cranial nerve is affected in Bell's Palsy?

CN VII - facial nerve

Which cranial nerve can be tested by asking the patient to squeeze their eyes shut?

CN VII - facial nerve

Which three nerves can be tested by asking the patient to repeat the phrase pa, ka, ta?

CN VII - facial, CN IX - glossopharyngeal, CN XII - hypoglossal

Damage to which nerve causes deafness?

CN VIII - vestibulocochlear

Problems in balance may follow trauma to which nerve?

CN VIII - vestibulocochlear

Which cranial nerve can slow the heart rate?

CN X - vagus

Which cranial nerves innervates most of the visceral organs?

CN X - vagus

Which cranial nerve is also known as "the wanderer" because it travels extensively, innervating many of the visceral organs of the thorax and abdomen?

CN X - vagus nerve

Which cranial nerve arises from upper spinal cord segments and then travels upward through the foramen magnum before traveling to innervate two major (and large) muscles of the head and neck?

CN XI - spinal accessory

Which cranial nerve will you be testing if you ask the patient to raise their shoulders, or to turn their head and resist you trying to push it back?

CN XI - spinal accessory

All of the following statements are TRUE about spinal nerves and cranial nerves EXCEPT: Spinal nerves are mixed nerves with both sensory and motor nerve fibers. Cranial nerves extend from the brain to structures in the head and neck. Spinal nerves can form nerve plexuses which means that a single skeletal muscle can be innervated by nerve fibers from multiple spinal cord levels. Spinal nerves travel from the spinal cord to the brain, where they are then called cranial nerves.

Spinal nerves travel from the spinal cord to the brain, where they are then called cranial nerves.

The tibial nerve innervates all of the following muscles EXCEPT: gastrocnemius biceps femoris semitendinosus adductor longus

adductor longus

Where will cerebrospinal fluid be found in this image? (#10) subarachnoid space central canal deep to the arachnoid mater between the arachnoid mater and pia mater

all of the choices are correct

Which nerve plexus contains nerves that travel to the upper limb?

brachial plexus

In the video, Dr. Jaworski mentions that the spinal levels C3, C4, C5 innervate an important structure in the ventral body cavity by repeating this phrase "C3, 4, 5 keeps the _____ alive!" What is this structure?

diaphragm

Sensory information enters the spinal cord on the

dorsal side

Sciatica is a condition that usually results from compression of nerve roots that contribute to formation of the sciatic nerve. In this condition, a patient may experience pain radiating

down the posterior of the lower limb

The dorsal root ganglion contains the cell bodies of neurons carrying which type of information?

sensory

Spinal nerves the innervate the upper extremity come from _____ spinal levels.

cervical

This area of the spinal cord is known as the... (#12)

cervical enlargement

All of the pairs below are correctly matched expect one. Which pair shows an INCORRECT match? cranial nerve VI: eye movement cranial nerve III: oculomotor nerve cranial nerve IV: sensory optic nerve: sensory cranial nerve III: pupillary constriction

cranial nerve IV: sensory

Which cranial nerves carry the sensation of taste?

facial, glossopharyngeal, vagus

Which nerve can be tested by asking the patient to stick out their tongue?

hypoglossal

What is one way that cranial nerve V, or trigeminal nerve can be tested?

lightly brushing the face on the forehead, cheeks and jawline and ask the patient whether each side feels the same

The sciatic nerve is formed from which nerve plexus?

lumbosacral plexus

Which nerve is negatively affected during carpal tunnel syndrome?

median nerve

The femoral nerve innervates

muscles in the anterior compartment of the thigh

The peripheral nervous system or PNS is made up of

nerves and ganglia

Droopy upper eyelids, double vision and dilated pupils can result from injury to the

oculomotor nerve

Which combination of cranial nerves is responsible for controlling eye movement?

oculomotor, trochlear, abducens

Which cranial nerve can be assessed by testing whether the patient's visual fields are intact?

optic nerve

Name the most important nerve from the cervical plexus and identify the structure it innervates.

phrenic nerve; diaphragm

Which nerve plexus gives rise to the sciatic nerve?

sacral plexus

How do spinal nerves leave the bony vertebral column to get to the peripheral?

the travel through intervertebral foramina

What is the name of the very large nerve that can be found on the surface on the pontine protuberance? It has 3 sensory divisions and 1 motor division.

the trigeminal nerve

The two divisions of the sciatic nerve are the

tibial and common fibular nerves

All of the following nerves innervate muscles of the forearm, EXCEPT: radial nerve medial nerve ulnar nerve tibial nerve

tibial nerve

Which nerve is injured when you hit your "funny bone"?

ulnar nerve

What structure contains the axons of motor neurons leaving the spinal cord?

ventral root

Which of the listed nerves are purely sensory? vestibulocochlear or CN VIII glossopharyngeal or CN IX oculomotor or CN III trigeminal or CN V

vestibulocochlear or CN VIII