OS III - Neuroanatomy Flashcards
1
Q
What does the central part of ectoderm differentiate into?
A
The neural plate
2
Q
What does the neural plate form? Week 4.
A
Neural plate forms the neural tube in 4th week.
3
Q
what cause the neural tube to differentiate along dorsal and ventral axis?
A
Growth signaling factors
- Shh - sonic hedgehog
- BMP - bone morphogenic protein
4
Q
Where does Shh, sonic hedgehoge come from?
A
notocord
5
Q
where does BMP come from?
A
Growth signal factor from ectoderm.
6
Q
Along what axis does the neural tube form?
A
The Rastro-caudal axis.
7
Q
What does primary neurulation involve? 2
A
- Columnirization of the exhisting epithelium
- roling or folding of the epithelium.
8
Q
What does secondary neurlation involve? 2
A
- Condensation of mesenchyme to form a rod
- rod undergoes epithelial transition to form neural tube.
9
Q
What are the two mechanisms that can form neural tube from neural plate?
A
Primary and secondary neurulation.
10
Q
How many waves of closure to close neural tube and when?
A
- 5 separate waves of closure
- days 19-21
11
Q
Where does closure of neural tube happen first?
A
Closure begins in brain stem region and near the upper spinal cord.
12
Q
Where does neural tube closure happen after the upper spinal cord and brain stem close?
A
The head and neck close after the brain stem and upper spinal cord.
13
Q
Where does the last of the neural tube closure happen?
A
caudal region, sacraum
- It fuses with the rest of the spinal cord
14
Q
What type of nerualation forms the sacral neural tube?
A
secondary neurulation.
15
Q
what need to close for complete CNS formation?
A
Rostral and caudal neuropores.
16
Q
What is anencephaly?
A
- lack of skull and cerebrum formation
- only brain stem is intact
17
Q
Failure of what causes anencephaly?
A
Failure of second wave closure of neural tube where the head and neck close
18
Q
What is spina bifida
A
Incomplete formation of spinal cord and overlying vertebrae that remain unfused and open.
19
Q
What are three of the variable degrees of severity of spina bifita?
A
- spina bifida occulta
- meningocele
- myelomeningocele
20
Q
Failure of what causes spina bifida?
A
Incomplete closure of caudal neuropore, at the junction of waves one and 5.
- junction of primary and secondary neurelulation
21
Q
What differentiate the CNS recions?
A
Dialations and flectures of neural tube.
22
Q
what are the 4 regions of the CNS?
A
- hindbrain
- midbrain
- diencephalon
- telencephalon
23
Q
What does the Hindbrain consist of? 2
A
Medulla
Pons
myelencephalon - medulla
metencephalon - Pons
24
Q
What does the mid brain consist of? 1
A
Mesencephalon - midbrain
25
What is the diencephalon mad of? 3
Thalamus
Hypothalamus
epithalamus
26
What is the telencephalon made of ?
The cerebral hemispheres.
27
what does the neural tube space become?
spinal canal
| ventricles of brain stem and cerebral hemispheres
28
What direction is caudal
toward spinal cord
29
what direction is Rostral?
toward front of brain
30
What ensure that the optical axes are at right angles to vertebral column
Cephalic flexure
31
What is the cephalic flexure related to?
cranial base flexion
32
What is the pontine flexure
Areas of 4th ventricle and pons enlargement
33
What is derived from edge of pons?
cerebellum
34
What is the gray matter of the spinal cord divided into?
sensory
autonomic
motor
35
What is white matter divided into?
```
Ascending tracts (mostly dorsal)
Descending tracts (more ventral)
```
36
What are functionally specific areas of grey matter?
Rexed's lamina
37
Of the grey matter in spinal cord, what are the dorsal, intermediate and ventral areas responsible for?
Dorsal - sensory
Intermediate - autonomic
Ventral - motor
38
What does the dorsal horn of the spinal cord convey?
Convey sensations to neurons into lamina 2-5.
- tactile
- proprioceptive
- pain
- temperature
39
What do second order neurons from the dorsal horn do?
- send info to local spinal areas
| - ascend to brain stem and thalamus
40
What is the intermediate region of the gray matter of spinal cord a site for?
Preganglionic autonomic neruons
- visceral motor VM
- autonomic
41
What is the ventral horn a site for?
Efferent motor neurons that project to skeletal muscle groups. (exiting)
42
What does the white mater of the spinal cord separate into?
Dorsal funiculi
ventral funiculi
lateral funiculi
43
what are the spinal tracts of white matter formed by?
Axons of ascending and descending neurons
44
What is the function of the dorsal funiculus?
Dorsal columns carry tactile info to the brain stem and thalamus
45
What tracts make up the lateral funiculus? 3
- lateral corticospinal tract
- spinocerebellar tracts
- anterolateral system
46
What does the lateral corticospinal tract do?
Lateral corticospinal tract is the major descenting motor tract from cortex
47
What is the function of the spinocerebellar tracts?
tactile and proprioceptive information to the cerebellum
48
What conveys pain and temp to the thalamus?
the anterolateral system of the lateral funiculus
49
what are the two parts of the ventral funiculus? 3
- anterior (ventral)corticospinal
- vestibulospinal
- reticulospinal
50
What part of the ventral funiculus makes up the descending motor pathways from cortex?
anterior corticospinal
51
What part of ventral funiculus makes up the descending motor pathway from the brain stem? 2
- vestibulospinal tract
| - reticulospinal
52
What tract surrounds grey matter and interconnects various spinal levels?
propriospinal tract.
53
What does the brain stem contain?
- regulatory centers
- cranial nerves
- sensory pathy
- motor pathways
- reticular foramen
54
What regulatory centers does the brain stem contain?
respiration
cardiovascular
gi
swallow, vomit, cough, pneumotaxic
55
What are the cerebellar peduncles for?
Input and output tracts between cerebellum and pons
56
What do the different regions of the cerebellum regulate?
- muscle coordination
- motor planning
- procedural memory
- balance
- eyemovement
57
What are the 5 key parts of the midbrain?
- substantia nigra
- periaqueductal grey (PAG)
- superior/inf colliculi
- Red nucleus
- cerebral peduncle
58
What is the substantia niagra for?
Midbrain
| - dopamine modulation of motor control
59
What is the Periaqueductal grey for of the midbrain?
regulates pain and stress responses
60
What regulates pain and stress responses?
periaqueductal grey of the midbrain. PAG
61
what does the superior and inferior colliculi do?
Superior - looks
| Inferior - listens
62
What does the inferior colliculi of midbrain do?
listens - help locate where sound is coming from
63
What is the red nucleus of midbrain a part of?
Red nucleus is a part of the descending motor pathway
64
What is the cerebral peduncle used for.
sensory and motor pathways to and from spinal cord, brain stem and cortex.
65
what makes up the sensory and motor pathways to and from the spinal cord, brain stem and cortex
cerebral peduncle of midbrain
66
What are the nuclear regions of the diencephalon
thalamus
hypothalamus
epithalamus
67
What contains the pineal gland
eipthalamus
68
what are the paired structures that flank the third ventricle?
hypothalamus
69
What does the thalamus contain?
several nuclei that process and distribute sensory and motor information to and from the cerebral cortex
70
What direction does information move through the thalamus?
to and from cerebral cortex
71
What type of information is distributed through the thalamus?
both sensory and motor
72
What is the anterior pituitary derived from?
- ectoderm primordial
| - Rathke pouch from primitive oral cavity
73
what system of vessels extend from hypothalamus into anterior pituitary?
Portal system of vessels
74
What is the posterior pituitary derived from?
neural tube
75
what connects the posterior pituitary to the hypothalamus?
neurosecretory axons that release hormones into blood
76
Which part of pituitary is connected to hypothalamus via axons and which is connected bvia blood vessels
Blood vessesl - anterior
| axons - posterior
77
What type of axons extend into posterior pit?
neurosecretory neuronal axons
78
What are the 4 areas of the motor cortex?
- primary
- premotor
- supplementary
- brocas speech area
79
where is the motor cortex?
frontal lobe
80
What are the 4 areas of the somatosensory cortex?
primary
secondary
association
wernikes language area
81
where is the somatosensory cortex?
parietal lobe
82
three areas of auditory cortex of temporal lobe?
primary
secondary
associaton
83
what are the three parts of occipital lobe, visual cortex
primary
secondary
association
84
what is the insula?
gustatory
visceral
emotional cortex within the lateral sulcus
85
Reticular formation is often associated with what?
arousal
attention
motivation
wakefulness
86
what direction of flow of info through reticular formation?
neurons receive general sensory input and project it into the cortex , limbic structures and spinal cord
87
Where is reticular foramen? what is it?
it is in the brain stem area, it is make up of nuclei along the medial axis
88
what are the 5 basal ganglia
```
gaudate
putamen
globus dallidus
substantia nigra
subthalamus
```
89
What are the caudate and putamen basal ganglia called together?
striatum
90
What basal ganglia are embedded in central white matter?
striatum - caudate/putamen
| GP - globus pallidus
91
What basal ganglia is in the mid brain? 2
substantia nigra
| subthalamus
92
What 3 parts make up limbic cortex?
- orbital/ medial prefrontal cortex
- cingulate gyrus
- parahippocampal gyrus
93
What are the 5 parts of the limbic system
- limbic cortex
- ant/med dorsal thalamic nuc
- hippocampus
- amygdala
- ventral stratum
94
What does the ventral striatum (basal ganglia) include?
nucleus accumbens
95
shape of limbic system
C shaped cluster of structures that extends into temporal lobe
96
where is hippocampus in relation to lobes?
temporal lobe
97
what interconnects cortical regions of brain?
white matter axon bundles
98
what type of whie matter axon bundles interconnect cortices
superior longitudinal
| occipito frontal fascuculi
99
what fibers connect local gyri
arcuate fibers
100
what connects the hemispheres?
corpus callosum
101
along what axis are cortices connected?
longitudinal
102
Signs of Spina bifida occulta
Tuft of hair, incomplete vertebral arch but spinal cord and dura matter remain in proper place.
103
What is spina bifida meningocele?
Spinal cord remains in place but the dura mater balloons out of spinal column
104
What is spina bifida myelomeningocele
Where both spinal cord and dura is outside the vertebral column.
