Nervous System Review

Question 1

2 components of the nervous system

Answer 1

Central Nervous System (CNS)
Peripheral Nervous System (PNS)

Question 2

Central Nervous System (4)

Answer 2

Cerebrum (cerebral hemispheres)
Brain Stem
Cerebellum
Spinal Cord
- ascending tracts
- descending tracts
- lower motor neurons
- upper motor neurons
- reflex arc

Question 3

Three major components of the Brain

Answer 3

1. cerebrum
2. cerebellum
3. brain stem

Question 4

Cerebrum (4 lobes)

Answer 4

L + R cerebral hemispheres
Frontal Lobe
Temporal Lobe
Parietal Lobe
Occipital Lobe
- in addition, cerebrum also encloses basal ganglia, thalamus, hypothalamus, and limbic system

Question 5

Frontal lobe

Answer 5

Controls higher cognitive functions, memory, voluntary movements, Broca’s area in (L) hemisphere for expressive speech and language. inhibitions.

Question 6

Temporal Lobe

Answer 6

Integration of somatic, visual, and auditory data and Wernicke’s area (responsible for receptive language)

Question 7

Parietal Lobe

Answer 7

Composed of sensory cortex
Controls and interprets spatial formation

Question 8

Occipital Lobe

Answer 8

Process visual data

Question 9

Brain stem consists of: (3)

Answer 9

Midbrain
Pons
Medulla

Question 10

Medulla

Answer 10

vital centres concerned with respiratory, vasomotor, and cardiac function are located in medulla. PROTECT IT. breathing, heartrate all controlled there.

Question 11

Cerebellum

Answer 11

• located inferior to occipital lobe
• coordinates voluntary movement & maintains trunk stability and equilibrium
• receives information from cerebral cortex, muscles, joints and inner ear

Question 12

Ventricles

Answer 12

4 cavities within the brain, filled with CSF

Question 13

Cerebro-Spinal Fluid (8)

Answer 13

1. Clear, colourless
2. circulates within subarachnoid space
3. provides cushioning for brain and spinal cord
4. Allows fluid shifts from cranial cavity to spinal cavity
5. Carries nutrients
6. Absorbed through arachnoid villi
7. CSF pressure is measured in pts with actual or suspected intracranial diseases
8. increased in CSF pressure indicates increase in intracranial pressure (ICP) -> can lead to herniation of the brain

Question 14

Cerebral Circulation: Blood Brain Barrier

Answer 14

• physiological barrier between blood capillaries and brain tissue
• protects brain from certain harmful agents, while allowing nutrients
• affects penetration of drugs -> only certain ones
  lipid-soluble drugs enter quickly (smaller molecules)
  water-soluble and ionized drugs enter slowly (larger molecules)

Question 15

Protective Structures of Brain

Answer 15

• meninges
• skull
• vertebral column

Question 16

Meninges

Answer 16

3 layers of protective membranes that surround brain and spinal cord:
- dura matter
- arachnoid
- pia matter

Question 17

Dura matter

Answer 17

Outermost layer
Falx cerebri - fold of dura two cerebral hemispheres
Tentorium cerebelli - a fold of dura that separate cerebral hemispheres from posterior fossa (which contains brain stem & cerebellum)

Question 18

Arachnoid Matter

Answer 18

Delicate, impermeable membrane, lies between dura matter and pia matter
Arteries, veins, and cranial nerves passing to and from brain must mass through subarachnoid space (space between arachnoid layer and pia mater)

Question 19

Pia matter

Answer 19

delicate, innermost layer of meninges

Question 20

Intracranial Pressure: Skull

Answer 20

A closed space what does this mean for rising pressure? - no where to go.
Volume from 3 components - cerebrospinal fluid, blood and brain tissue.

Question 21

Primary Injury vs Secondary Injury

Answer 21

Primary injury - at the initial time of injury
Secondary injury - resulting from hypoxia, ischemia, hypotension, edema or increased ICP that follows a primary injury and can occur several hours to days after the injury