Central Nervous System

Question 1

Gray matter

Answer 1

Contains the cell bodies of neurons

Cortex and deep grey matter

Question 2

White matter

Answer 2

Contains myelinated axons

Below the cortex and running along tracts in the brain

Question 3

Diencephalon

Answer 3

The posterior part of the forebrain
Contains hypothalamus, thalamus, epithalamus, ventral thalamus and third ventricle
Relay and processing center

Question 4

3 things that make up the basal ganglia (and 3 functions)

Answer 4

Caudate nucleus
Putamen
Globis palladis
These supply inhibitory stimuli to skeletal muscles, coordinate skeletal muscle contractions, and block unwanted muscle contractions

Question 5

4 lobes of the cerebrum and what are they responsible for

Answer 5

Frontal: controls movement, behavior, emotions, higher intellectual functions
Parietal: integrates sensory inputs like touch and controls language (ability to understand words)
Temporal: hearing, smelling, memory and expression (ability to express words)
Occipital: vision

Question 6

Thalamus

Answer 6

Important for integrating sensory stimuli (like pain and touch) and determinant of conciousness

Question 7

Gray and white matter in brain vs spinal chord

Answer 7

In the spinal chord the gray matter is internal and the white matter is external
In the brain the gray is on the outside and the white is on the inside

Question 8

Hypothalamus

Answer 8

Connects many different parts of the brain and regulates many body functions like appetite, thirst and temperature
Controls the pituitary by secreting factors that regulate hormonal release

Question 9

Functions of each part of the brainstem

Answer 9

Midbrain: visual, auditory reflex centers
Medulla oblongata: cardiac, vasomotor, respiratory centers
Pons: contains bundles of axons carrying info to and from the brain

Question 10

Cerebellum

Answer 10

Coordinated voluntary movement
Controls ability to stand upright without falling over
Controls muscle toone

Question 11

3 inputs to the cerebellum

Answer 11

1. Sensory info carried by the spinal chord
2. Vestibular organ in the inner ear
3. Motor impulses from cerebral cortex

Question 12

What type of neurons synapse in the dorsal versus anterior horn of the spinal chord?

Answer 12

Dorsal: sensory neurons
Anterior: motor neurons (lower motor neurons)

Question 13

3 layers of the meninges

Answer 13

1. Dura: outer layer
2. Arachnoidae: middle layer
3. Pia: innermost layer

Question 14

Another word for neuronal cell body

Answer 14

Perikaryon

Question 15

4 types of glial cells

Answer 15

Astrocytes: support cells
Oligodendrocytes: wrap around axons and form myelin sheaths
Microglia: resident macrophages
Ependymal cells: line ventricles and make CSF

Question 16

Dysgraphic disorders

Answer 16

Incomplete fusion of the neural tube and defective formation of meninges, calvaria, or vertebras

Question 17

Malformations in

1. Ancephaly
2. Meningocele
3. Spina bifida
4. Myelomeningocele

Answer 17

1. No brain
2. Vertebrae doesn’t form and meninges protrude through bony defect
3. No vertebral arches, resulting in exposure of meninges or spinal cord to outside
4. Same as 2, but along with a bit of the spinal cord protruding

Question 18

Epidural Hematomas

Answer 18

Between skull and dura
Rupture of middle meningeal artery (fracture related)
Tight space, so hematoma takes hours to develop and its localized
Coma can result; lethal if unrecognized because arterial bleeding will continue

Question 19

Subdural hematomas

Answer 19

Between dura and arachnoid
Caused by blunt trauma
Ruptured bridging veins
Venous bleeding occurs slowly, so may be asymptomatic
Can produce headache, coma, death

Question 20

Subarachnoid hemorrhages

Answer 20

Located between arachnoid and pia

Caused by traumatic contusion of the brain and/or the rupture of congenital aneurysms (in the circle of Willis)

Question 21

Intracerebral hemorrhages

Answer 21

Rupture of intracerebral vessels
Common complication of head trauma, gunshot wounds
Nontraumatic forms include stroke
Common with poor clotting, so blood spreads easily

Question 22

Stroke

Answer 22

Sudden persistent loss of brain function from a vascular cause
Risk factors include hypertension, smoking, diabetes, high cholesterol

Question 23

Global ischemia

Answer 23

If many vessels are narrowed they can develop small infarcts, which over time can lead to dementia
Hypoperfusion from cardiac arrest or peripheral bleeding
Watershed infarcts (systemic hypotension lowers the perfusion from both sides and the area in the border zone becomes hypoxic)
Laminar necrosis from hypoperfusion

Question 24

Cerebral infarct

Answer 24

Caused by thrombotic occlusion, thromboemboli
Pale or hemorrhagic infarct (reperfusion)
Surrounding brain tissue: edematous
Fluid filled cavity
Never heals (damage is permanent)
Clinical presentation depends on site of occlusion
Acute stroke can kill
MCA stokes result in contralateral hemiplegia and sensory loss, global aphasia in the dominant hemisphere

Question 25

Intracerebral hemorrhage

Answer 25

``` Most caused by arterial hypertension Others from vascular malformations Basal ganglia, cerebellum and pons Well-circumscribed Clinical features often severe, high mortality ```

Question 26

Multiple Sclerosis

Answer 26

Demyelinating, chronic disease (presumed autoimmune) Women > men Most common neurological disease in young adults Mediated by helper lymphocytes, macrophages, and B cells/plasma cells Exacerbation and remission episodes Sensory and motor abnormalities Unpredictable course

Question 27

Oligoclonal T cells

Answer 27

Oligoclona proliferations of sensitized T cells is considered to be the basis of MS lesions Macrophages also found in the lesions

Question 28

2 possible courses for MS

Answer 28

Relapsing remitting type: works well with therapy (beta interferons, etc), during remission function returns to normal, dampens down symptoms of inflammation Chronic: permanent due to neurodegeneration

Question 29

What is found in early vs late lesions in MS

Answer 29

Early: contain demyelinated axons surrounded by lymphocytes and foamy macrophages Late: demyelinated axons and astrocytes

Question 30

Wernicke-Korsakoff syndrome (deficiency in, symptoms)

Answer 30

``` Vitamine B1 (thiamine) deficiency W part is more acute (abnormal eye movements) and K part is more chronic (loses short term memory) ```

Question 31

Vitamin B12 deficiency

Answer 31

Leads to loss of sensation and motor function with uncoordinated movements plus psychiatric symptoms Leads to subacute combined degeneration of the ascending tracts of the spinal cord

Question 32

Pellagra | deficiency in, symptoms

Answer 32

Nicotinic acid deficiency | Dermatitis, diarrhea, delirium/dementia

Question 33

Myelopathy vs neuropathy

Answer 33

M: damage to spinal cord N: damage to peripheral nerves Both can be a direct effect of alcoholism

Question 34

Alzheimers Disease

Answer 34

Sporadic neurodegenerative disease Genes increase levels of beta-amyloid and apoE4 Atrophy greatest in frontal and temporal lobes Dementia Requires nursing care, death due to physical deterioration or infection Can see histological changes in cortex, neuritic plaques, neurofibrillary tangles

Question 35

Parkinson's Disease

Answer 35

Subcortical neurodegenerative disorder Decreased number of dopaminergic neurons in the substantial nigra (appears pale) Disturbances of movement, TRAP Depression, dementia common Presence of Lewy bodies (with alpha synuclein)

Question 36

TRAP

Answer 36

Tremor, rigidity, brady or akinesia, postural instability | In Parkinson's disease

Question 37

Huntington's Disease

Answer 37

Autosomal dominant, familial Gene is huntingtin gene on chromosome 4 with CAG trinucleotide repeat expansion Disease only occurs when the repeats exceed a threshold Involuntary, gyrating movements, progressive dementia Atrophy of cortex, caudate, putamen Loss of neurons and reactive gliosis

Question 38

Amyotrophic Lateral Sclerosis

Answer 38

Neurodegenerative disease, most sporadic 10% have mutations in copper-zinc superoxide dismutase (SOD1) gene Loss of motor neurons in cortex, brainstem and spinal cord and of corticospinal tracts in spinal cord Weakness and wasting of muscles, fasciculations, slurred speech Incurable and progressive disease

Question 39

Epilepsy (2 types)

Answer 39

Generalized: discharges all over the brain - leads to aura, tonic clonic seizures and post ictal drowsiness, can be controlled Focal: one spot that can be detected - many causes - drugs or surgery

Question 40

One differences between malignant tumors in the CNS and malignant tumors everywhere else

Answer 40

Malignant tumors in the CNS do NOT metastasize, they just grow rapidly

Question 41

Astrocytomas

Answer 41

Solid cerebral tumors in adults, cystic cerebellar tumors in children Well-differentiated astrocytes Progress into lesions Cannot distringuish from glioblastoma multiforme

Question 42

Glioblastoma Multiform

Answer 42

Most common CNS tumor Lateral hemispheres Gross appearance: parts are necrotic/yellow, hemorrhagic/red, or white, irregularly shaped, poor demarcations, butterfly appearance Cells are very atypical

Question 43

Oligodendrogliomas

Answer 43

Cerebral hemispheres Well circumscribed, partially cystic, calcified Well-differentiated Possible progression to GBM

Question 44

Ependymomas

Answer 44

Children: ventricles, adults: spinal cord Ependymoma or filum terminale Tumor cells line papillary structures or form rosettes

Question 45

Medulloblastoma

Answer 45

Cerebellum Childhood Cells are primitive neuroectodermal cells Cells may enter CSF and metastasize to other sites in the CNS Poor prognosis

Question 46

Meningiomas

Answer 46

Arise from meninges and are dural based Mostly benign Most located near midline, base of brain, along spinal cord Cause epileptic seizures or motor deficits Excellent prognosis - surgery is curative unless malignant or in unreachable location

Question 47

Neurofibromatosis type 1 vs 2

Answer 47

1: produces multiple peripheral neurofibromas 2: produces acoustic schwannomas as well as multiple meningiomas

Question 48

3 most common cancers to metastasize to brain

Answer 48

Lung Breast Melanoma