Introduction

Question 1

Major Components of Nervous System (CNS, PNS)

Answer 1

Central Nervous System (CNS) – brain and spinal cord
Peripheral Nervous System (PNS) – spinal nerves, cranial nerves, and visceral/autonomic NS
Spinal nerves (31 pairs) – provide both sensory and motor innervation
• Named by where they exit the spinal column
• Can combine to form plexus or larger nerves
Cranial Nerves (12)
• 2-12 originate from the brain – provide motor and sensation to the head
o Exception: CNX (vagus nerve) – provides innervation outside of head/neck region
Visceral/Autonomic Nervous system - NO voluntary motor function

Question 2

Terms of Direction (Rostral, Caudal, Dorsal, Ventral)

Answer 2

o Rostral – at the forehead
o Caudal – back of head
o Dorsal – superior
o Ventral – inferior

Question 3

Terms of Direction (Median plane, sagittal plane, coronal/transverse plane, horizontal plane)

Answer 3

o Median plane – straight down midline of the brain dividing into right and left side
o Sagittal plane – parallel to the median plane but not exactly centered
o Coronal/transverse plane – divides brain into front and back
o Horizontal plane – divides brain into top and bottom; parallel to the floor

Question 4

Meninges

Answer 4

– protective layer of connective tissue composed of 3 layers

Dura mater – outermost, tough layer; composed of an inner and outer layer
Sinuses – located between the inner and outer layer; contain venous blood that drains into the jugular veins

Arachnoid mater – middle, more fibrous layer
Subarachnoid space – deep to arachnoid mater but superficial to pia mater; contains blood vessels and cerebrospinal fluid (CSF)

Pia mater – deepest layer and lies directly on the cortex of the brain

Question 5

White vs. Gray Matter

Answer 5

o White Matter – made of glia cells & neuronal tracts; inner portion of brain; outer portion of SC
o Gray Matter – composed of neuronal cell bodies; outer surface of brain; inner surface of SC

Question 6

Cerebral Cortex Sulci/Fissures

Answer 6

– deep grooves/fissures; used clinically to determine different lobes
• Longitudinal fissure – contains the corpus callosum (major commissure)– white matter that acts as a pathway connection between left and right sides of the brain
• Lateral fissure – inside the brain; separates temporal from frontal/parietal lobe
• Central fissure – separates frontal lobe from parietal lobe

Question 7

Cerebral Cortex Gyri and Lobes

Answer 7

– wavy parts that form lobes of the brain
• Frontal lobe
o Anterior – planning, reasoning
o Posterior – motor control, speech
• Temporal lobe
o Dorsal/posterior – hearing
o Medial – memory processing
o Anterior – higher order visual & auditory processing; semantic processing
• Parietal lobe – sensory; attention; spatial processing
• Occipital lobe – visual processing

Question 8

Cerebral Cortex Basal Ganglia

Answer 8

– located in center of the brain; composed of specialized nuclei (putamen, caudate nucleus, and globus pallidus)
• Help the cortex with movement and routine learned behaviors
• Without basal ganglia the cortex can’t function

Question 9

Limbic System

Answer 9

– aid in memory, motivation, emotion – close to basal ganglia
 Hippocampus – memory; controls visceral nervous system
 Amygdala

Question 10

Thalamus, Hypothalamus, Pineal Gland

Answer 10

o Thalamus – relay center for the sense
o Hypothalamus – helps maintain homeostasis through stimulation of the visceral/ANS
o Pineal Gland – serves as our biological clock

Question 11

Cerebellum

Answer 11

-coordination and balance

Question 12

Brainstem

Answer 12

• Brainstem – continues inferiorly to become the spinal cord
o Mesencephalon/Midbrain – relay center between spinal cord & cortex; visual & auditory reflexes
o Pons – provides a relay between cerebral cortex and cerebellum
o Medulla – most inferior – respiration and heart rate

Question 13

Spinal Cord

Answer 13

– continuous with the medulla; receives information and provides motor function for entire body except head and neck
o Ascending Pathway – generally used to describe sensation signals going towards the brain
o Descending Pathway – generally used to describe motor commands away from the brain
o White matter – contains the axons
 Dorsal white matter – sensory
 Ventral white matter - motor
o Gray matter – shaped like a butterfly and contains the neuron cell bodies

Question 14

Ventricular System, Functions and Direction of Flow

Answer 14

– structures in the brain that contain CSF
o Choroid plexuses – forms CSF – 90% water
o Functions of CSF
 Provide shock protection to the brain
 Delivery of nutrient and get rid of waste
 Compensation for changes in intracranial blood pressure by allowing for flow between the brain and spinal cord
o Direction of Flow: lateral ventricle (biggest one)  3rd ventricle  cerebral aqueduct  4th ventricle  central canal of spinal cord

Question 15

Ventricular System and Lumbar Punctures

Answer 15

between L3/L4 vertebrae– can be used to test for infections in brain because of continuous flow of CSF from brain to spinal cord