Chappter 7

Question 1

What are the 3 types of white matter in the cerebral hemispheres?

Answer 1

1. Association fibers
2. Commissural fibers
3. Projection fibers

Question 2

Association fibers purpose and location

Answer 2

Run anterior to posterior
Communicate within the hemisphere

Question 3

Superior longitudinal fasciculus

Answer 3

Association fibers
Connects:
Frontal to temporal
Frontal to parietal
Temporal to parietal
Important in speech-language-hearing association

Question 4

Arcuate (arch) fasciculus

Answer 4

Association fiber - part of superior longitudinal fasciculus
Connects same regions as superior longitudinal fasciculus
CORE OF NEURAL SUBSTRATE
Important for speech and language

Question 5

Commissural fibers

Answer 5

Medial to lateral
Hemisphere to hemisphere - connect homologous areas of the brain across the midline
Corpus Callosum is primary
Anterior Commissure is secondary (runs temporal to temporal)

Question 6

Projection fibers

Answer 6

Interconnect the cerebral cortex with the brainstem and spinal cord
Runs superior to inferior
Internal capsule and corona radiata - important

Question 7

What is the corona radiata

Answer 7

Projection fibers that fan out in the cerebral cortex as they come up
Corticofugal and corticopetal axons as they exit the internal capsule

Question 8

What is the internal capsule?

Answer 8

Projection fibers that have sensory and motor tracts
Corticospinal and corticobulbar tracts

Question 9

What is the meninges?

Answer 9

Layers of non-neural connective tissue that completely encapsulates and protects the CNS
Made up of fiber blasts
Has 3 layers: dura mater, arachnoid layer, pia mater

Question 10

Dura mater

Answer 10

Outermost layer of meninges
2 layers
3 important areas: falx cerebri, falx cerebelli, TENTORIUM cerebella
IS NOT FLEXIBLE
Damage: subdurmal hematoma

Question 11

Falx cerebri

Answer 11

Dura mater that separates the left and right hemisphere of the cerebrum

Question 12

Falx cerebelli

Answer 12

Separates the cerebellar hemispheres
Dura mater

Question 13

TENTORIUM cerebella

Answer 13

Dura mater
B/w the occipital lobe and cerebellum
Separates cerebrum from cerebellum

Question 14

What is the arachnoid layer

Answer 14

Second layer of meninges
Weblike appearance
More resilient to strain
Acts like a shock absorber b/c circulates CSF
Has many arteries and veins which makes it susceptible to bleeding
Damage subarachnoid hemorrhage
Cisterns: where CSF pools

Question 15

Pia mater

Answer 15

Innermost layer of meninges
Adheres to cerebrum and cerebellum
Suspends the spinal cord from dural layer

Question 16

Dural folds

Answer 16

Compartmentalize the tissues of the brain in the cranial vault and form
Falx cerebri, falx cerebelli, and TENTORIUM cerebelli

Question 17

Function of cerebrospinal fluid (CSF)

Answer 17

Helps maintain intracranial pressure
Removes waste from CNS
Nourishes the nervous tissue
Supportive role
Keeps brain in protective pool
Circulates around CNS
Secreted by choroid plexus

Question 18

2 lateral ventricles IN cerebral hemispheres

Answer 18

Separated by septum pellucidum
Connects to 3rd ventricle by interventricular foramina
Which contributes to drainage of CFS

Question 19

3rd ventricle

Answer 19

Sits at midline of diencephalon b/w thalamic nuclei and intrathalamic adhesion

Question 20

4th ventricle

Answer 20

Cerebral aqueduct connects 3rd and 4th ventricle
Dorsal brainstem and cerebellum
Divides the pons and medulla and runs into the spinal cord
2 ports that connect to the cisterns that are helping circulate the CSF

Question 21

Blockage in ventricles

Answer 21

Causes hydrocephalis - failure to absorb and fluid builds up and pressure on cerebrum affects cognitive functioing

Question 22

Arterial blood

Answer 22

Comes from the heart to the brain
Carries oxygen

Question 23

Venous blood

Answer 23

Does not have oxygen
Goes from brain to heart

Question 24

From handout

Answer 24

Arterial blood system and posterior circulatory

Question 25

Arteries in circle of Willis - see diagram in handout Both anterior and posterior

Answer 25

ACA - anterior cerebral artery - anterior communicating artery MCA - middle cerebral artery IntC - internal carotid artery Posterior communicating artery PCA - posterior cerebral artery

Question 26

Anterior arterial system originates from what major branch of the aorta

Answer 26

Common carotid

Question 27

Posterior arterial system originates from what major branch of the aorta

Answer 27

Subclavian artery

Question 28

Posterior arterial system

Answer 28

Comes up from the arm starts at Subclavian artery Vertebral artery splits l/r and runs up medulla. Between medulla and pons l/r merge and become basilar artery

Question 29

Purpose of circle of Willis

Answer 29

Helps regulate arterial flow b/w hemispheres and vascular circuit Connects via internal carotid artery and vertebral carotid artery Tubes help funnel blood through vascular system

Question 30

Purpose of venous sinuses

Answer 30

Drain deoxygenated blood back to the heart Waste products, carbon dioxide and toxins All blood drains through the INTERNAL JUGULAR by way of venous sinuses SEE DIAGRAM FROM HANDOUT

Question 31

Venous drains in order

Answer 31

Superior Sagittal sinus Inferior sagittal sinus Straight sinus L/r transverse sinus Confluence

Question 32

3 vascular pathologies

Answer 32

Aneurysm Stroke Arteriovenous malformation (AVM)

Question 33

Cerebral aneurysms

Answer 33

Asymptomatic - sometimes a headache or signs of stroke that come and go Located in circle of Willis Abnormal dilation of artery Usually found incidentally Treated by vascular clipping or endovascular coiling

Question 34

85% of CVAs are

Answer 34

Ischemic/embolic

Question 35

Embolism/Ischemic

Answer 35

Blood flow is stopped by embolism in arteries so blood does not flow past. Or not as much blood flow from ischemic Deficit is where blood is to getting to Symptoms are according to where blockage is, maybe nausea and headache

Question 36

Treatment for ischemic or embolic stroke

Answer 36

Clot busting drug TPA or TMK If can identify within 4 1/2 hours can get drug and dissolve clot. Will not resolve everything but sill stop symptoms from worsening If identified as clot they can remove clot through thrombectomy (significant procedure)

Question 37

Hemorrhagic stroke

Answer 37

Bleeding in brain 10% - much more devastating Symptoms can be focal or headache Gradual progression of deficits as blood keeps seeping into brain Vomiting, confusion, loss of consciousness, fixed pupils Treatment - potentially surgery, evacuation of hematoma, take out section of skull to relieve swelling

Question 38

Arteriovenous malformations

Answer 38

Tangles of small blood vessels Congenital Found incidentally Symptoms can be migraines and seizures Treatment - embolization which blocks blood flow in the tangles, or can remove