Neurology

Question 1

What does a pupillary light reflex (PLR) indicate?

Question 2

Which toxin should be considered if a patient presents for tremors/seizure activity?

Answer 2

Metaldehyde which is a pesticide/mollusicide used to control slugs and snails in gardens

Question 3

Which nerve fibers are responsible for sensing temperature?

Answer 3

Somatic afferent

Think AFter you touch something hot you sense it

Question 4

Patients suffering from upper motor neuron injury can also suffer dysfunction of what?

Answer 4

The urinary bladder

Question 5

Define ANS, SNS, PNS, CNS/PNS

Answer 5

The autonomic nervous system (ANS) divides into two branches: sympathetic nervous system (fight or flight) and parasympathetic nervous system (rest and digest/maintenance functions).

The nervous system is also divided into the central nervous system (CNS; brain and spinal cord) and peripheral nervous system (PNS; outside of the brain and spinal cord).

The ANS is part of the peripheral nervous system and includes sympathetic and parasympathetic.

The ANS, SNS and PNS control organs such as stomach, heart, bladder, intestine, blood vessels and sweat glands.

Question 6

How many cranial nerves are there? What are the functions of each?

Answer 6

There are 12 cranial nerves.

I. Olfactory - smell
II. Optic - vision/certain eye reflexes
III: Oculomotor - control most eye muscles
IV: Trochlear - control eye muscles (other)
V: Trigeminal - 3 branches: 1. Motor nerve to muscles of the jaw, 2. Sensory nerves to the mouth and nasal cavity, 3. Sensory nerves that carry pain sensations from cornea (most sensitive outer part of the eye ball)
VI: Abducent - control muscles of the eye (other)
VII: Facial - control expression (ears, eyelids, nose and mouth)
VIII: Vestibulochochlear - 2 parts: 1. Chochlear nerve (responds to sound) 2. Vestibular nerve (functions to maintain posture and balance)
IX: Glossopharyngeal - sensory and motor control of the throat and vocal cords
X: Vagus - sensory and motor control for major internal organs including heart and digestive
XI: Spinal Accessory; sensory and motor information for the muscles of the head and upper neck
XII: Hypoglossal - motor nerves to the tongue

Question 7

What is the difference between decerebrate rigidity and decerebellate rigidity postures?

Answer 7

1. Decerebrate: opisthotonus, all limbs extended, diminished mental status.
2. Decerebellate: opisthotonus, forelimbs extended, hip flexed, hind limbs flexed OR extended, normal mental status