(01) Introduction

Question 1

What is the body’s most complex organ?

Answer 1

• The Brain

Question 2

How many neurons are found in the mammalian brain? Are they all in use?

Answer 2

• billions - yes

Question 3

What do sensory circuits (sight, touch, hearing, smell, taste) do?

Answer 3

• bring info to the nervous system to make the animal aware of the environment

Question 4

What do motor circuits do?

Answer 4

• send info from the brain and spinal cord to muscles and glands to produce a response (movement or secretion)

Question 5

The principles of the neurological examination are based on what?

Answer 5

• knowledge of the anatomy and physiology of the central nervous system (CNS) and the peripheral nervous system (PNS).

Question 6

What does the nervous system include?

Answer 6

brain, spinal cord, and all the nerves that communicate between tissues and the brain and spinal cord

Question 7

What two types of cells comprise the peripheral and central nervous system?

Answer 7

• neurons and glia

Question 8

What are the specialized cells of nervous tissue that can conduct electrical signals and transmit information from one part of the nervous system to another or to peripheral targets such as muscle?

Answer 8

• neurons

Question 9

What are the supporting cells of the nervous system?

Answer 9

• glia (have a broad range of functions that will be learned later)

Question 10

What types of signals do neurons use to communicate? What are action potentials? What are synapses?

Answer 10

• electrical and chemical - electrical signals carried along the axons of neurons - chemical or electrical junctions that allow electrical signals to pass from one neuron to the next or to a target cell like muscle

Question 11

What is the central nervous system composed of? What is it housed in?

Answer 11

• the brain and spinal cord - cranial cavity and vertebral canal

Question 12

What is the peripheral nervous system composed of?

Answer 12

• ganglia and peripheral nerves that lie outside the brain and spinal cord

Question 13

What does an understanding of the differences between the PNS and CNS help us with?

Answer 13

• clinical diagnosis of neurological disease or injury

Question 14

What is the largest part of the brain? What does it control? What are three more things that is does? What parts is it divided into?

Answer 14

• cerebrum - learning and behavior - involved in interpreting sensation, gives an animal its personality and is associated with higher level functions - frontal, parietal, temporal, occipital (based on areas beneath calvaria)

Question 15

Blue

Answer 15

Frontal Lobe of cerebrum

Question 16

Red

Answer 16

Parietal Lobe of Cerebrum

Question 17

Orange

Answer 17

Occipital

Question 18

Green

Answer 18

Temporal Lobe of Cerebrum

Question 19

What does the brain stem connect? What is it responsible for? Where is the approximate division between the brain stem and the spinal cord?

Answer 19

• the brain to the spinal cord
• basic functions of life including heart rate, breathing and swallowing
• at the foramen magnum

Question 20

What are the 4 major parts of the brain stem?

Answer 20

• Diencephalon, Midbrain, Pons, Medulla

Question 21

What is the most rostral portion of the brain stem called? What is its function?

Answer 21

• the diencephalon (thalamus, hypothalamus, etc.)
• Coordinates and regulates all functional activity of the cerebral cortex; integration center of the autonomic nervous system; vision, hearing

Question 22

What are the clinical signs of damage to the diencephalon?

Answer 22

• altered levels of conciousness, endocrinopathies, behavioral abnormalities, disorders of thirst, appetite and temperature regulation

Question 23

What part of the spinal cord is located between the pons caudally and the diencephalons rostrally? What cranials nerves does it serve as a site of exit for?

Answer 23

• midbrain
• cranial nerves 3 & 4

Question 24

What are the functions of the midbrain?

Answer 24

• visual reflexes, hearing reflexes, eye movement, body movement

Question 25

What are clinical signs of damage to the midbrain?

Answer 25

decreased state of conciousness, loss of papillary light reflex, pupils dilated, extensor rigidity in all 4 limbs; contralateral paralysis or weakness with unilateral lesions

Question 26

What part of the spinal cord is located between the medulla and the midbrain (just underneath the cerebellum)? What are its functions?

Answer 26

- The Pons - Gives rise to the trigeminal nerve and thus controls jaw opening and receives sensation from the head and face. It also has parts that are important for the level of conciousness and for sleep

Question 27

What are clinical signs of damage to the pons?

Answer 27

Hopping and placing deficits, muscle atrophy of the head, loss of facial sensation, vital sign changes

Question 28

What forms the most caudal part of the brain stem and is located between the spinal cord and the pons? What are its functions? Which nerves exit from it?

Answer 28

- Medulla - maintaining vital body functions (breathing and heart rate), pain modulation - Several cranial nerves

Question 29

What are clinical signs of damage to the medulla?

Answer 29

- head tilt, facial paralysis, difficulty swallowing, atrophy of the tongue, regurgitation, vital sign changes, vestibular signs, nystagmus

Question 30

What is the structure located dorsal to the pons and medulla and connected to these structures by the cerebellar peduncles? Was is its function?

Answer 30

- the cerebellum - processes input from other areas of the brain, spinal cord and sensory receptors to provide precise timing for coordinated, smooth movements of the skeletal muscular system

Question 31

What are clinical signs following damage to the cerebellum?

Answer 31

- ataxia (lack of voluntary coordination of muscle movements) of all four limbs and head, intention tremors, vestibular signs

Question 32

What forms the caudal part of the CNS (also the most important part of the CNS from a veterinary clinical standpoint)? What are its functions?

Answer 32

- the spinal cord - Connects much of PNS to brain, sensory info (nerve impulses) reaching the spinal cord primary afferent nuerons is transmitted to higher brain regions - signals arising in the motor areas of the brain travel back down to the cord to affect motor neurons and influence muscle contraction

Question 33

What are clinical signs of damage to the spinal cord?

Answer 33

- CERVICAL/UPPER THORACIC - ataxia; tetraparesis; ipsilateral hemiplegia; hopping, placing and proprioceptive deficits; hyperactive spinal reflexes; neck pain - LUMBOSACRAL - ataxia rear limbs, paraparesis, hopping, placing and proprioceptive deficits, depressed or absent rear limb spinal reflexes, deep pain alterations

Question 34

Is each part of the CNS anatomically distinct? What does this mean?

Answer 34

- yes - damage to different brain regions will result in different deficits and clinical signs

Question 35

Both the spinal cord and brain consist of what type of matter?

Answer 35

- white matter and grey matter

Question 36

What is white matter? Why does it look white?

Answer 36

- bundles of axons (may have a myelin covering which gives white appearance in dissected brain)

Question 37

What is grey matter comprised of?

Answer 37

- neuronal cell bodies, dendrites, and glial cells

Question 38

How is matter arranged in spinal cord? How about the brain of mammals? Brain of lower vertebrates (fish and amphibians)?

Answer 38

- white matter at the surface, gray matter inside - grey matter at the surface, white matter inside - White matter on outside (surface), gray matter inside

Question 39

green

Answer 39

diencephalon

Question 40

red

Answer 40

midbrain

Question 41

blue

Question 42

orange

Answer 42

medulla

Question 43

red and blue

Answer 43

- white and gray

Question 44

red and blue

Answer 44

white and grey