Lecture 2 Anatomy (CNS Overview) Flashcards
(104 cards)
1
Q
What is the brain made up of?
A
100 billion neurons
1 trillion neuroglia
-Neurons are primarily interneurons (associative) involved in associative function (intellect, emotions, behavior, and memory)
2
Q
Brain development:
Describe the stages -
A
Ectoderm -> neural fold -> neural tube -> 3 primary vesicles -> 5 secondary vesicles
3
Q
5 Principle parts of the brain (derived from secondary vesicles):
A
- Telencephalon - cerebral hemispheres, basal ganglie, limbic system
- Diencephalon - thalamus, hypothalamus, epithalamus
- Mesencephalon (midbrain) - cerebral peduncles, corpus quadrigemina
- Metencephalon - cerebellum, pons
- Myelencephalon - medulla oblongata
4
Q
Brain stem (parts):
A
- Medulla oblongata (myelencephalon)
- Pons
- Midbrain (mesencephalon)
5
Q
Protective covering of brain:
Start with scalp -
A
1. Scalp - skin, CT, aponeurosis, lipid, and periosteum 2 Cranial bones (skull) 3. Epidural space with far 4. Dura matter 5. Subdural space - with interstitial fluid 6. Arachnoid mater 7. Subarachnoid space - with CSF 8. Pia matter
6
Q
Folds of the dura matter (hold brain in place)
Falx cerebri -
Falx cerebelli -
Tentorium cerebelli -
A
Falx cerebri - sagittal between cerebral hemispheres
Falx cerebelli - sagittal between cerebellar hemispheres
Tentorium cerebelli - transverse between cerebrum and cerebellum
7
Q
What is brain’s normal fuel source and how much does it use during rest?
A
Glucose (unable to store)
Uses 20% of bodies oxygen and glucose
8
Q
Blood brain barrier composed of 3 parts:
A
- Tight junctions between blood vessel endothelial cells
- Continuous endothelial cell basement membrane
- Astrocytes (neuroglia) wrapped around endothelial cell basement membrane
9
Q
What can/can’t cross BBB?
Not found in which organs (give general name and name 3 organs)?
A
Can - lipid soluble, hydrophobic substances Can't - Water, hydrophilic substances Circumventricular organs: 1. Hypothalamus 2. Pituitary 3. Pineal Gland
10
Q
Medulla Oblongata (Myelencephalon): Overall Functions -
A
- Contains nuclei for vital centers and cranial nerves
2. Signal Propagation via ascending (sensory signals) and descending (motor signals) tracts
11
Q
Medulla Oblongata (Myelencephalon): Nerve tracts -
A
Nerve tracts - (bundles of axons) both sensory (ascending) and motor (descending)
12
Q
Medulla Oblongata (Myelencephalon): Pyramids -
A
Pyramids - paired ventral surface ridges that contain motor descending tracts
13
Q
Medulla Oblongata (Myelencephalon): Decussation of pyramids -
A
Decussation of pyramids - motor tracts from the right brain cross to control muscles on the left side and motor tracts from left brain cross to control muscles on the right side
*motor
14
Q
Medulla Oblongata (Myelencephalon): Olives -
A
Olives - paired bulges lateral to pyramids which contain the inferior olivary nuclei which links brain and spinal cord motor signals to the cerebellum for perception of time
15
Q
Medulla Oblongata (Myelencephalon): Fasciculus gracilis and fasciculus cutaneous -
A
Fasciculus gracilis and fasciculus cutaneous - ridges found on dorsal medulla which relay sensory ascending input to opposite side of the brain
16
Q
Medulla Oblongata (Myelencephalon): Decussation of the medial lemniscus -
A
Decussation of the medial lemniscus - crossover of ascending sensory input to the contralateral brain hemisphere
*sensory
17
Q
Medulla Oblongata (Myelencephalon): Nuclei
A
Nuclei - masses of neuronal cell bodies
- Vital body functions: cardiovascular, respiratory
- CN nuclei for CN 8, 9, 10, 11, & 12
18
Q
Pons: Where is it found? What part of brain is it? Contains - Functions -
A
- Found on ventral surface of brain stem
- Apart of metencephalon with cerebellum (which is not apart of the brain stem)
Contains - CN nuclei 5, 6, 7 and ascending and descending tracts
Functions - information relay for cerebellar hemispheres
19
Q
Midbrain:
Where is it found?
What CN?
A
- Mesencephalon
- CN 3, 4
20
Q
Midbrain:
Superior colliculi -
A
Superior colliculi - reflex movement of eye, head, and neck to visual and other stimuli
21
Q
Midbrain:
Inferior colliculi -
A
Inferior colliculi - reflex movement of head and neck to auditory stimuli
22
Q
Midbrain:
Cerebral peduncles -
A
Cerebral peduncles - contain descending motor axon tracts from cerebral hemispheres to spinal cord, medulla and pons
-Ascending sensory axons going to cerebrum
23
Q
Midbrain:
Cerebral peduncles -
A
Cerebral peduncles - contain descending motor axon tracts from cerebral hemispheres to spinal cord, medulla and pons
-Ascending sensory axons going to cerebrum
24
Q
Midbrain:
Red nucleus and substantia nigra -
A
Red nucleus and substantia nigra - function to modify motor signals
25
Functions of the midbrain?
1. Relay motor impulses from cerebral cortex
| 1. Relay sensory impulse from spinal cord to thalamus
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Reticular (net) formation -
Diffuse structure, composed of areas of gray matter interspersed among areas of white matter in central portions of diencephalon, brain stem, and spinal cord
27
Reticular functions -
1. Alerting cerebral cortex to sensory signals
2. Reticular activating system function in maintaining consciousness and awakening from sleep by stimulating the cortex
3. Filter sensory input to remove unimportant input (prevent sensory overload)
4. Efferent motor function in maintaining muscle tone
28
Cerebellum:
What part of brain?
Compose of?
```
-Metencephalon with pons
Composed of:
1. Vermis (worm) which splits the two hemispheres
2. Cerebella hemispheres
3. Peduncles
```
29
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Cerebellum:
Cross section anatomy
Cortex -
Folia -
Arbor vitae nerve tracts -
Cerebellar nuclei -
```
Cortex - gray matter
Folia - ridges
Arbor vitae nerve tracts - white matter
Cerebellar nuclei - gray matter within arbor nuclei
30
Cerebellar Functions:
1. Smooth and coordinate cerebral control of skeletal muscle movements to facilitate complex muscle activity
2. Regulate muscle tone
3. Posture and balance
31
Diencephalon:
| Composed of -
```
- Not part of brainstem
Composed of:
1. Thalamus
2. hypothalamus
3. Epithalamus
4. Subthalamus
```
32
Diencephalon:
1. Thalamus
What is it composed of?
What are functions?
- Composed of paired masses of mixed gray nuclei and white tracts connected by intermediate mass (crossover point)
Functions:
- Sensory (visual, auditory, smell, taste, somatic sensation) relay to the correct region of the cerebral cortex
- Refine motor signals with the basal nucleus
33
Diencephalon:
2. Hypothalamus
Function (general) -
Composed of -
- Function: maintain homeostasis
- Circumventricular organ
Composed of:
- mammillary bodies visible on inferior surface
-infundibulum connects pituitary (hypophysis) to the hypothalamus
34
Diencephalon:
2. Hypothalamus
Specific Functions -
1. Control of autonomic nervous sustem (heart, gut, bladder)
2. Control endocrine system - control pituitary
3. Regulate emotional behavior (limbic system)
4. Regulate eating and drinking
4. Control body temp
5. Regulate circadian rhythms and state of consciousness
35
Diencephalon:
3. Epithalamus
Composed of -
Functions -
Composed of:
1. Pineal gland - endocrine gland secretes melatonin
2. Habenular nuclei (paired)
Functions:
1. Pineal gland melatonin production to set biological clock
2. Habenular - emotional response to smell
36
Diencephalon:
4. Subthalamus
Composed of -
Functions -
```
Composed of:
1. Subthalamic nuclei
2. Parts of red nuclei
3. Parts of substantia nigra
Functions:
1. Connects to cerebellum and motor cortex for control of body movements
```
37
Circumventricular Organs:
What are they?
Function?
Name the 3
- Areas of brain that do not have BBB therefore are able to monitor chemical changes in blood
- Function as part of body's internal sensory system to maintain homeostasis
- Hypothalamus, pineal, pituitary (hypophsysis)
38
Basal Ganglia:
What part of brain?
What does is consist of?
Function?
- Telencephalon
- Consists of paired nuclei (gray matter)
- Function in control of skeletal muscle movement (motor neuron) and muscle tone
39
Limbic system:
What part of brain?
Composed of what?
Describe what it is
- Telencephalon and Diencephalon
- Composed of paired nuclei, tracts, and cortex (parts of frontal/parietal/ and temporal lobes)
- Primitive brain function in emotional aspects of behaviors and memory/pain, pleasure, affection, and anger to determine feelings
40
Cerebrum:
| Composed of -
-Telencephalon
Composed of:
1. Cerebral cortex (gray matter) - 10s of billions of associative (inter) neurons typically arranged in 6 layers to allow vertical integration
2. Cerebral white matter containing 2 types of neurons:
-Association fibers - connect diff gyri in same hemi
-Commissural fibers - connect diff gyri in opposite hemi
-Projection fibers - connect cerebrym to rest of body (sensory/motor)
41
Cerebrum:
| Functions
1. Conscious sensation (receive conscious sensory input)
2. Voluntary motor activity (sends voluntary motor output)
3. Higher brain function (cognition, association of sensory input with memory to produce more memory, language, abstract thought - humanity)
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```
Cerebrum: Surface anatomy
Gyri -
Sulci -
Fissures -
Longitudinal fissure -
Hemispheres -
Corpus callosum -
```
Gyri - Ridges
Sulci - shallow grooves (valleys)
Fissures - deep grooves
Longitudinal fissure - separates R/L hemispheres (contains falx cerebri)
Hemispheres - R/L sides of cerebrum
Corpus Callosum - Large connection of commissural tracts connecting R/L hemispheres
43
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Cerebrum: Surface anatomy
Lobes -
Central sulcus -
Precentral gyrus -
postcentral gyrus -
```
Lobes - frontal, parietal, temporal, occipital, insula
Central sulcus - Separates frontal and parietal lobes
Precentral gyrus - ant to central sulcus, voluntary somatomotor area
postcentral gyrus - post to central sulcus, conscious somatosensory area
44
Cerebrum: Surface anatomy
Lateral cerebral fissure (sulcus) -
Parieto-occipital sulcus -
Lateral cerebral fissure (sulcus) -separates frontal and temporal lobes (leads to insula)
Parieto-occipital sulcus - separates parietal and occipital lobes
45
Frontal Lobe -
| Location
Frontal lobe - located anterior of central sulcus and medial the lateral sulcus
46
Frontal Lobe:
Precentral Gyrus -
Somatotopic -
Homunculus -
1. Primary motor cortex controlling voluntary movement on contralateral side of the body
2. Somatotopic - specific regions of the precentral gyrus control muscles in specific body regions
3. Homunculus - depicts somatotopic organization of precentral gyrus and relative cortical contributions to a particular body region
47
Frontal Lobe:
Frontal eye field -
Broca's area -
Frontal eye field - coordinated R andL eye movements (conjugate eye movements)
Broca's Area - L hemisphere only (dominant hemi), coordinates motor speech
48
```
Frontal Lobe:
Prefrontal cortex -
Location?
Input?
Output?
Functions?
```
Prefrontal cortex - rostral most part of frontal lobe (primary target for lobotomy)
1. Input from all regions of cortex and limbic system
2. Output to wide variety to subcortical nuclei thalamus, basal ganglia and brain stem
3. Functions to regulate visceral, emotional, and cognitive (intellectual) processes
49
Frontal Lobe:
| Cingulate Gyrus -
Cingulate Gyrus - medial surface (within longitudinal fissure) of frontal and parietal lobs
- Limbic cortex for emotional behavior, autonomic response, and learning
50
Insula:
Location?
Functions?
1. Located within the lateral sulcus where frontal, parietal, and temporal lobes come together
2. Functions in integration of sensory input for:
- Taste and olfaction
- Viscerosensation (interoreceptors)
- Pain
- Balance??
51
Parietal Lobe:
| Post central gyrus -
Post central gyrus
1. Primary sensory area - tactile and proprioceptive sensation
2. Somatotopic - specific regions receive sensory input from specific body regions
3. Homunculus - depicts somatotopic organization of post central gyrus and relative cortical contributions to a particular body region
52
Parietal Lobe:
| Supramarginal and Angular gyrus -
Supramarginal and Angular gyrus - Receive visual and auditory input for perceptional discrimination and integration
53
Parietal Lobe:
Wernicke's area
Location?
Function?
- Located in both parietal (supramarginal and angular gyri) and temporal lobes of the left hemi (dom hemi)
- Functions in comprehension of spoken language and works with Broca's area to formulate a verbal response
54
Parietal Lobe:
| Superior parietal lobe -
- Association area integrating sensory and motor areas to program complex motor responses
55
Occipital Lobe:
Superior medial surface -
Visual association cortex (nothing on back)
- Located caudal to the parietal-occipital sulcus on the medial border
Superior medial surface - (next to longitudinal fissure) primary visual cortex
56
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Temporal Lobe:
Transverse gyri Heschl -
Superior temporal gyrus -
Middle temporal gyrus -
Inferior temporal gyrus -
Parahippocampal gyrus and uncus -
```
Transverse gyri Heschl - medial aspect of superior temporal gyris = primary auditory cortex
Superior temporal gyrus - auditory association cortex
Middle temporal gyrus - perception and analysis of motion in the visual field
Inferior temporal gyrus - facial recognition in response to visual input
Parahippocampal gyrus and uncus - located on the inferior surface of temporal lobe, function with limbic system
57
Hemispheres: (separated and connected by?)
- Separated by longitudinal fissure
| - Connected by commissural fibers
58
Hemispheres:
| Hemispheric localization -
Hemispheric localization - functional difference exist between hemispheres = cerebral dominance
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Describe L vs R Hemi
Left - language interpretation and execution, numerical and scientific (abstract), reasoning
Right - musical, artistic, special and pattern interpretation, facial recognition, emotional content of language, mental images of visual, auditory, somatic, taste, and olfactory input
60
Cerebral dominance due to -
1. Unequal cortical representation of function in homologous regions of the 2 hemis
2. Diminished commissural cross connections between regions
- Visual cortex: temporal eye field is uncrossed
- Primary motor and sensory areas of the distal arm (handedness) and leg
61
Arterial blood supply:
| Origin of R internal carotid A
Origin of R internal carotid A: L ventricle -> ascending aorta -> brachiocephalic A -> R common carotid -> R internal carotid
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Arterial blood supply:
| Origin of L internal carotid A
Origin of L internal carotid A -> L ventricle -> ascending aorta -> aortic arch -> L common carotid -> L internal carotid
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Arterial blood supply:
| Origin of R vertebral A
Origin of R vertebral A -> L ventricle -> ascending aorta -> brachiocephalic A -> R subclavian a -> R vertebral a
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Arterial blood supply:
| Origin of L vertebral A
Origin of L vertebral A-> L ventricle -> ascending aorta ->aortic arch -> L subclavian a -> L vertebral a
65
Course of Internal Carotids through skull:
| Start with External opening of carotid canal in temporal bone ->
Carotid canal in petrous portion of temporal bone -> Internal opening of carotid canal in temporal bone -> crosses over foramen lacerum -> runs along base of sella turcica in carotid groove ->Turns up to join optic nerve at prechiasmatic groove
66
Branches of internal carotids:
| Opthalmic -
Opthalmic - runs with CN 2 supplying blood to the choroid/retina of the eye via central artery of the retina
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Branches of internal carotids:
| Posterior communicating A -
Posterior communicating A - part of circle of willis supplying the pituitary (hypophysis), infundibulum, hypothalamus, and thalamus (diencephalon)
68
Branches of internal carotids:
| Anterior choroidal A
Anterior choroidal A - Arises near middle cerebral a to supply choroid plexus of lateral ventricle, optic tract, internal capsule, and globus pallidus (basal nucleus)
- Deep structures of telencephalon
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Branches of internal carotids:
Anterior Cerebral A
What body regions and function would be affected by a stroke here?
Anterior Communicating -
Anterior Cerebral A - runs in longitudinal fissure above corpus callosum to medial aspect of frontal and parietal lobes
- Feet/legs
1. Anterior communicating - anastomosis between R/L anterior cerebral A
2. Other branches - to basal nucleus and limbic (deep telencephalon, inferior surface of frontal lobe = deep structures in telencephalon)
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Branches of internal carotids:
| Middle Cerebral Artery
Middle Cerebral Artery - runs in lateral sulcus to:
1. Lateral frontal lobe (Broca's, trunk, arm, face of precentral gyrus)
2. Lateral parietal (Wernicke's, trunk, arm, face of postcentral gyrus)
3. Insula (limbic: pain, olfaction, taste)
4. Lateral occipital
5. Medial/lateral temporal (primary auditory)
6. Sub-cortical deep structures (basal ganglia, internal capsule, limbic structures)
71
Course of Vertebral Arteries:
| Start with Transverse foramen of cervical vertebra->
From C1 transverse foramen -> bends medial to foramen magnum -> passes through foramen magnum -> ascends clivus -> R/L vertebrals fuse into basilar A
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Branches of Vertebral A:
Anterior Spinal A -
Posterior inferior cerebellar -
Posterior Spinal A -
Anterior Spinal A - to medial medulla (pyramids, medial lemniscus, MLF)
Posterior inferior cerebellar - Lateral medulla (spinothalamic tract, spinocerebellar tracts, spine nucleus of CN 5)
Posterior Spinal A - Branches of posterior inferior cerebellar a to dorsal medial medulla (cuneatus and gracilis)
73
```
Branches of basilar A:
Anterior Inferior cerebellar -
Labyrinthine A -
Pontine A -
Superior cerebellar A -
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Anterior Inferior cerebellar - to cerebellum and pons
Labyrinthine A - enters internal acoustic meatus to cochlea and vestibular apparatus
Pontine A - to pons
Superior cerebellar A - cerebellum ,, pons, and midbrain
74
Branches of basilar A:
| Posterior cerebral A -
Posterior cerebral A -
1. Cortex - medial (primary visual) and inferior occipital, inferior temporal
2. Subcortical structures - midbrain, subthalamus, and thalamus
75
Circle of Willis -
| What arteries makes up?
Circle of Willis - anastomosis between internal carotid a's and basilar a
1. Anterior communicating A
2. Anterior cerebral a
3. Posterior communicating A
4. Posterior cerebral A
76
Dural Artery -
Middle meningeal from maxillary A (off external carotid) via foremen spinosum
77
Venous Drainage of Brain:
| Dural Sinuses - (4)
Dural Sinuses:
1. Superior sagittal sinus - formed from superior margins of falx cerebri
2. Inferior sagittal sinus - formed from inferior margins of falx cerebri drains into ->
3. Straight sinus formed from junction of falx cerebri and tentorium cerebella
4. Occipital sinus - formed by junction of falx cerebella at attachment to occipital bone
78
All dural sinuses drain into ->
Confluence of sinuses - intersection of superior sagittal, straight, transverse, and occipital sinuses ->
1. Transverse sinus formed from junction of tentorium cerebella with occipital bone
2. Superficial veins
- > sigmoid sinus - continuation of transverse sinus in groove at junction of occipital and temporal bones
- > Internal Jugular vein
79
Venous Plexi:
```
Cavernous sinus
Pterygoid sinus
Basilar
Superior and inferior petrosal
-> drain into venous sinuses or jugular veins
```
80
Spinal Cord:
Runs from where to where?
Ends at...
Runs from medulla oblongata at foramen magnum/C1 (atlanto occipital joint) to L1/L2 intervertebral joint ending in conus medullaris
81
Protective coverings of spinal cord:
Skin -> hypodermis -> muscle
epidural space - with fat
dura mater - continuous with spinal nerve epineurium
subdural space - interstitial fluid
arachnoid mater
subarachnoid space - csf
pia mater - denticulate lig link pia to arachnoid mater
filum terminal links pia of conus medularis to sacrum/coccyx
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31 pairs spinal nerves (how many per area?)
```
8 cervical
12 thoracic
5 lumbar
5 sacral
1 coccygeal
```
83
Dorsal roots from spinal nerves -
- Sensory axons
- Somatosensory neurons
1. touch and proprioception are located medially
2. pain and temp are located laterally
- viscerosensory
84
Ventral roots from spinal nerves -
- Motor axons
Somatomotor neurons (ventral horn)
Autonomic (viscero) motor neurons (lateral horn)
85
How do spinal nerves exit the spinal cord (what foramen)?
Via intervertebral foramen
86
Cauda Equina -
What regions is it found in?
What is the space that is resides known as?
- Roots of spinal nerves from lumbar, sacral, and coccygeal regions
- Resides in enlarged subarachnoid space known as the lumbar cystern
87
Cervical enlargement -
| Lumbar enlargement -
Cervical enlargement - C5-T1 brachial plexus
| Lumbar enlargement - L1-S2 lumbosacral plexus
88
How is the spinal cord connected to the vertebral column and skull?
Denticulate Ligaments
Filum terminal:
-pial portion = filum terminal internum
-dural portion = filum terminal externum
89
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Movement of spinal cord:
Trunk extension -
Trunk flexion -
1. Unfolding of axon within endoneurium ->
2. Elastic deformation ->
```
Trunk extension - reduces stretch of cord
Trunk flexion - increase stretch
-Flex head at neck = cord stretches 10% post/6% ant
-Unfolding of axon within endoneurium -> 70% increase of length
-Elastic deformation (stretch thin) -> 30%
90
Movement of spinal cord:
| Trunk Rotation -
Trunk Rotation - stretches nerve roots and spinal nerves around bones forming the intervertebral foramen
Nerves/roots protected by:
1. Extra space of intervertebral foramen accommodates stretch (spinal n/roots occupy 23-50% of space)
2. Epidural fat in intervertebral space
3. Covering of dura mater
91
Spinal cord cross section anatomy:
| Grooves -
Grooves:
Anterior median fissure
Posterior median fissure
92
Spinal cord cross section anatomy:
| Gray matter -
Gray matter - H shaped central core containing neuron and neuroglia cell bodies, and unmyelinated neuron processes (axons and dendrites)
93
Spinal cord cross section anatomy (Gray matter):
| Dorsal (posterior) Horn -
Dorsal (posterior) Horn - composed of interneurons involved in sensory signaling
94
Spinal cord cross section anatomy(Gray matter):
| Ventral (anterior) Horn -
Ventral (anterior) Horn - composed of somatomotor neurons and interneurons (Renshaw cells) involved in motor signaling somtotopically organized
1. Medial ventral horn - axial muscles
2. Lateral ventral horn - appendicular muscles
3. posterior ventral horn - flexors
4. Anterior ventral horn - extensors
95
Spinal cord cross section anatomy(Gray matter):
| Lateral (intermediolateral) Horn -
Lateral (intermediolateral) Horn -
T1-L2 sympathetic preganglionic neurons
S2-S4 parasymp preganglionic neurons
96
Spinal cord cross section anatomy(Gray matter):
| Rexed's Laminae -
Rexed's Laminae - 10 histologic/functional regions of gray matter in dorsal and ventral horn
lamina 1 - marginal layer for noxious stimuli
lamina 2 - substantia gelatinosa for noxious stimuli
97
Spinal cord cross section anatomy(Gray matter):
| Grey Commissure -
Grey Commissure - connection between right and left gray matter
- Allows for signals to cross to opposite side
98
Spinal cord cross section anatomy:
| White matter -
White matter - contains ascending (sensory) and descending (motor) tracts (fasciculi) which are bundles of myelinated axons with a similar origin and terminal destination
99
Spinal cord cross section anatomy(White matter):
Dorsal (post) column (funiculus) -
Lateral Column (funiculus) -
Anterior (ventral) column (funiculus) (nothing on other side)
Propriospinal -
Dorsal (post) column (funiculus) - bundle of tracts (fascicula)
Lateral Column (funiculus) - posterior and anterior
Anterior (ventral) column (funiculus)
Propriospinal - axons that begin and end within the cord providing interconnection between tracts and gray matter for context
100
Spinal cord cross section anatomy:
| Central Canal -
Central canal - continous with fourth ventricle of the brain
- contains csf
101
Spinal Cord function -
Describe function
Flow
- Nerve impulse propagation between periphery (primarily trunk and appendiges) and the brain occurring in tracts of white matter
- Flow of impulses is two directional from periphery to brain (ascending sensory) and brain to periphery (descending motor)
- Somatic reflex control center
102
Spinal cord vasculature:
| 1. Primary arterial supply:
1. Primary arterial supply:
Cervical - vertebral arteries
Thoracic - posterior intercostal a
Lumbar - Lumbar a
103
Spinal cord vasculature:
| 2. Spinal branches off primary supply -
- Branch into dorsal and ventral segmental arteries that form:
1. Ant spinal a to deep ant cord regions
2. 2 posterior spinal a to feep posterior cord regions
3. Ant/post radicular to superficial spinal cord regions
104
Spinal cord vasculature:
| Veins -
1. Anterior Median Spinal v
2. Anterolateral spinal v
3. Posteromedian spinal v
4. Posterolateral spinal v
