9 Development of the Brain - M

Question 1

What is the order of neurulation?

Answer 1

neural plate –> neural groove –> neural tube

Question 2

What structure induces neurulation?

Answer 2

the notochord

Question 3

The caudal 1/3 of the neural plate develops in what?

Answer 3

future spinal cord

Question 4

What are the last two parts of the neural groove to close during neurulation?

Answer 4

Cranial & caudal neuropores

Question 5

which neuropore, cranial or caudal, closes last?

Answer 5

caudal neuropore (Day 27)

Question 6

Where does secondary neurulation occur?

Answer 6

the sacrum and coccyx

Question 7

What occurs during secondary neurulation?

Answer 7

the caudal eminence fuses with the caudal portion of the neural tube

Question 8

What cells are derived from neuroectoderm?

Answer 8

neurons of the CNS, glial cells, ependyma

Question 9

What type of glial cell is not derived from neuroectoderm?

Answer 9

microglial cells (macrophages); derived from mesenchymal cells

Question 10

NCCs give rise to which part of the nervous system?

Answer 10

the peripheral NS including all ganglia outside of the CNS

Question 11

The 4th pair of somites demarks what?

Answer 11

Marks which part of the NT will form the brain and which will form the spinal cord

Question 12

What are the 3 divisions of the NT that will develop into the brain?

Answer 12

Prosencephalon/forebrain, mesencephalon/midbrain, rhombencephalon/hindbrain

Question 13

The prosencephalon/forebrain divides to give rise to what 2 brain regions?

Answer 13

Telencephalon (cerebrum) and diencephalon

Question 14

The mesencephalon/midbrain gives rise to what brain region?

Answer 14

midbrain

Question 15

The rhombencephalon/hindbrain gives rise divides into what brain structures?

Answer 15

metencephalon (pons) and myelencephalon (medulla)

Question 16

When does the telencephalon begin to divide into two hemispheres?

Answer 16

by the 5th wk

Question 17

What flexure is found between the midbrain & hindbrain?

Answer 17

cephalic flexure

Question 18

What flexure is found between the hindbrain and the cervical region?

Answer 18

cervical flexure

Question 19

During what timeframe are the basal ganglia developing?

Answer 19

6th-32nd wks

Question 20

What structures are derived from the telencephalon? (6 major structures)

Answer 20

cerebral cortex, subcortical white matter, olfactory bulb/tract, basal ganglia, amygdala, hippocampus

Question 21

What structures are derived from the diencephalon? (4)

Answer 21

thalamus, hypothalamus, epithalamus (pineal gland), and eyes (optic nerve)

Question 22

Which 2 cranial nerves are derived from the midbrain?

Answer 22

oculomotor and trochlear

Question 23

What structures are derived from the midbrain?

Answer 23

cerebral peduncles, tectum, tegmentum, substania nigra, and periaquedutal gray matter

Question 24

What are the structures found in the tectum?

Answer 24

superior/inferior colliculi

Question 25

What is holoprosencephaly (HPE)?

Answer 25

incomplete separation of the cerebral hemispheres (errors during 5th wk)

Question 26

What other malformations are associated with HPE?

Answer 26

facial malformations (cleft lip/palate), orbital hypotelorism

Question 27

What two structures give rise to the pituitary gland?

Answer 27

1st PA ectoderm (Rathke's pouch) and neuroectoderm from forebrain (diencephalon)

Question 28

the 1st PA ectoderm gives rise to which part of the pituitary gland?

Answer 28

anterior lobe (adenohypophysis)

Question 29

Forebrain neuroectoderm gives rise to which part of the pituitary gland?

Answer 29

posterior lobe (neurohypophysis)

Question 30

What separates the developing spinal cord into anterior and posterior plates?

Answer 30

the sulcus limitans

Question 31

What are the 2 plates of the developing spinal cord?

Answer 31

alar plate (posterior), basal plate (anterior)

Question 32

What hormone signs for the rostral development of the alar plate?

Answer 32

BMP (review from MSK)

Question 33

Why does the alar plate derivatives ascend in the spinal cord?

Answer 33

because it gives rise to the sensory tracts

Question 34

Why does the basal plate derivatives descend in the spinal tract?

Answer 34

because it gives rise to the motor tracts

Question 35

What are the 3 zones of the developing spinal cord?

Answer 35

1. ventricular zone 2. intermediate zone 3. marginal zone

Question 36

What cells are found in the ventricular zone of the developing spinal cord?

Answer 36

germinal/ventricular cell --\> ependymoblast --\> epedymal/choroid plexus cells in the ventricular zone

Question 37

What cells are found in the intermediate/mantle zone of the developing spinal cord?

Answer 37

cell bodies (gray matter) of neurons and glial cells

Question 38

What cells are found in the marginal zone of the developing spinal cord?

Answer 38

axons of primary afferents/efferents and oligodendrocytes

Question 39

Which nuclei in the myelencephalon (medulla) are derived from the basal plate?

Answer 39

* hypoglossal nucleus * dorsal motor vagal nucleus * nucleus ambiguus

Question 40

Which nuclei of the myelencephalon are derived from the alar plate?

Answer 40

* vestibular nuclei * cochlear nuclei * soliatary nuclei * inferior olive * spinal trigeminal nuclei and tracts

Question 41

What nuclei of the metencephalon (pons) are derived from the basal plate?

Answer 41

* motor nuclei for CN 5, 6 and 7 * superior salivary nucules (CN 7)

Question 42

What nuclei of the metencephalon (pons) are derived from the alar plate?

Answer 42

* cerebellar anlage * cochlear nuclei * vestibular nuclei * solitary nucleus * pontine nuclei * *

Question 43

What nuclei of the mesencephalon are derived from the basal plate?

Answer 43

* red nuclei * oculomotor nuclei * edinger-westphal nuclei

Question 44

What nuclei of the mesencephalon are derived from the alar plate?

Answer 44

superior and inferior colliculi

Question 45

What is syringomyelia?

Answer 45

A cyst that occurs in the central canal and results in the accumulation of CSF in the cervical region

Question 46

syringomyelia is high associated with what type of congenital malformation?

Answer 46

Chiari type 1 malformations

Question 47

What type of gait patterns are associated with spasitc cerebral palsy

Answer 47

toe walking and scissor gait

Question 48

Described the types of movements associated with athetoid cerebral palsy?

Answer 48

slow writhing movements of extremities and/or trunk (serpent type movements)

Question 49

What type of movements are associated with ataxic cerebral palsy?

Answer 49

uncoordinated, weakness, and shaking during voluntary movements; damage to cerebellum

Question 50

Arnold-Chiari malformations are due to errors in the development of what part of the brain?

Answer 50

hindbrain

Question 51

Chiari type 1 malformations are the result of what developmental error?

Answer 51

herniation of cerebellar tonsil through the foramen magnum

Question 52

Chiari type 1 malformations are highly associated with what other pathology?

Answer 52

syringomyelia

Question 53

What are some signs of Chiari type 1 malformations?

Answer 53

* head/neck pain * lower cranial nerve problems (CN 5-12)

Question 54

What pathology doe this patient have?

Answer 54

Chiari type 1 malformation; may also have syringomyelia

Question 55

How are arnold-Chiari type 2 malformations described?

Answer 55

Herniation of medulla and cerebellum through the foramen magnum

Question 56

What pathology highly associated with Arnold-Chiari type 2 malformations?

Answer 56

spina bifida (3 types so look them up if you don't remember)

Question 57

When are Arnold-Chiari malformations typically diagnosed?

Answer 57

during fetal development by MRI (look at brainstem & lumbar region)

Question 58

What pathology is a result of a large cyst in the posterior fossa that is continuous with the 4th ventricle

Answer 58

Dandy-Walker malformation/cyst

Question 59

What foramina can be affected by a Dandy-Walker cyst?

Answer 59

Foramina of Luschka and Magendie

Question 60

What brain structure can be affected by a Dandy-Walker cyst?

Answer 60

Cerebellum

Question 61

What is the purpose of brain gyri and sulci?

Answer 61

Increases the amount of brain matter that can develop in the cranial vault; also decreases the length of axons & allows for faster processing speeds

Question 62

What is lissencephaly or agyria?

Answer 62

SMOOTH BRAIN d/t incomplete or failure of neuronal migration during 12-24th wks

Question 63

What cells are derived from the NCC regarding the PNS

Answer 63

* dorsal root ganglia * sensory ganglia of cranial nerves * otic, pterygopalatine, ciliary, mandibular * Schwann cells * sympathetic ganglia

Question 64

When during development does myelination occur?

Answer 64

late fetal period through first postnatal year

Question 65

What are the 4 types of spina bifida?

Answer 65

* Spina Bifida occulta * meningocele * meningomyelocele * myelocele/myeloschisis

Question 66

What is anencephaly?

Answer 66

Neural tube failure that results in the absence of **parts of the brain, skull, and scalp**

Question 67

What is encephalocele

Answer 67

* incomplete closure that results in sac-like protrusions from the head * *may or may not contain herniated of brain tissue*

Question 68

What spinal cord defect does this patient have? what other malformation may this patient have?

Answer 68

Patient has spina bifidia occulta, may also have Chiari type 1 malformation

Question 69

What is this? What else might the patient have?

Answer 69

myelomeningocele; Chiari type 1 malformation

Question 70

What part of the neural plate do the NCCs develop from?

Answer 70

Neural crest

Question 71

The crainal 2/3rds of the neural plate develops into what?

Answer 71

the 4th pair of somites = future brain