TEST 4 BRAIN ANAT & PHYS Flashcards
(302 cards)
1
Q
What divides the L hemisphere from the R hemisphere of the brain?
A
Longitudinal fissure
2
Q
Wide, deep separation of the brain tissue
A
Fissure
3
Q
Infolding on the surface of the brain
A
Sulcus (sulce)
4
Q
Upfolding on surface of the brain
A
Gyrus (gyri)
5
Q
Separates the frontal lobe from the parietal lobe on each side of the brain
A
Central sulcus
6
Q
Locations of the primary MOTOR cortices on each side of the brain
A
Precentral gyrus (gyri)
7
Q
Location of the primary SENSORY cortices on each side of the brain
A
Postcentral gyrus
8
Q
What divides the parietal and occipital lobes from each other?
A
Division based off of function, NO anatomic demarcation that separates them
9
Q
Separates temporal lobe from the frontal lobe and the temporal lobe from most of the parietal lobe
A
Lateral Fissure
10
Q
This is below the hemispheres of the brain, composed of tracts. It connects the R and L hemispheres so that each side of the brain knows what the other side is doing
A
Corpus callosum
11
Q
Just the below the corpus callosum is the lateral ________ where CSF is.
A
Lateral ventricle
12
Q
Most inferior part of the brain stem
A
Medulla
13
Q
The opening below the medulla that separates most inferior brainstem to most superior SC
A
Foramen magnum.
14
Q
What 3 structures compose the Brainstem?
A
Midbrain (mesencephalon)
Pons
Medulla oblongota
15
Q
What 2 structures compose the Diencephalon
A
Thalamus
Hypothalamus
16
Q
There are both ascending and descending pathways that MUST pass through the medulla to get info to higher brain centers and back to SC/skeletal muscle. TRUE/FALSE
A
TRUE
17
Q
Where are the decussation of the pyramids located
A
Anterior/inferior surface of the medulla
18
Q
This is where descending motor pathways cross over to the other side of the SC. Responsible for L side of brain controlling R side of body visversa
A
Decussation of the pyramids
19
Q
About _____% of descending motor pathways will cross over to the other side of the SC when they get to the decussation of the pyramids
A
85%
20
Q
Located in the medulla, recieve input from the inner ear and play a role in maintaining balance
A
Olives
21
Q
Where are the inspiratory and expiratory centers located in the brainstem?
A
Medulla
22
Q
Nerve cell bodies (nuclei) located in the medulla
A
CN IX. glossopharyngeal X. vagus XI. Spinal accessory XII. Hypoglossal
23
Q
These nuclei are related to CN IX and X, and play a role in the baroreceptor reflex.
A
Nucleus Solitarius
Nucleus Ambiguus
24
Q
Where do we find the baroreceptors for CN 9 and 10?
A
IX (glossopharyngeal): carotid sinuses; bifurcation of the internal carotids
X (vagus): Aortic arch
25
What activates the baroreceptors?
Increase in blood pressure
26
Increase in BP = activated baroreceptors = increase in ________transmission through the __________ portions of CN IX and X.
Increase in IMPULSE tx through the SENSORY portions of IX and X
27
As the impulses transmission approaches medulla, the pathways come together to form _________ and enter nucleus _________.
Tractus solitarius and enters nucleus solitarius
28
When nucleus solitarius activated, sends message to _________ which is the CV output center.
Nucleus ambiguus
29
When nucleus ambiguus activated, it excites what receptors?
Central Alpha II receptors
30
When central alpha II receptors are activated, it decreases ________ outflow and increases ________ outflow.
Decreases SNS outflow and increases PNS outflow
31
What happens with PNS outflow to help bring BP down?
HR decreases
Decreased strength of contraction
Blood vessels dilate
32
If we have low BP, the baroreceptors and nuclei are NOT excited and we end up having increased ________ outflow.
How does this increase BP?
Increases SNS outflow
HR increases, Contractility increases, and blood vessels constrict
33
These 3 structures are involved in modulating pain transmission and help decrease the intensity of pain.
- Raphe magnus nucleus
- Reticularis paragigantocellularis
- Periaquaductal gray matter
34
What type of NT and receptors are abundant at the sites that modulate pain tx?
Endogenous opioids and MU, Kappa, Alpha receptors
35
All of these autonomic reflexes are mediated through nuclei in the medulla. (5)
```
CV/vasomotor center
Swallowing
Vomiting
Coughing
Sneezing
```
36
This is located in the 4th ventricle and highly related to N/V
Chemoreceptors trigger zone (CTZ)
37
The CTZ is located OUTSIDE/INSIDE the BBB and comes DIRECTLY/INDIRECTLY in contact with CSF.
CTZ is OUTSIDE the bbb
| DIRECTLY in contact with CSF
38
Any noxious stimuli to the CTZ leads to DECREASED N/V. TRUE/FALSE
FALSE
| Any noxious stimuli leads to N/V
39
What type of drugs are directed at receptors in the CTZ?
Antiemetics
40
There are only ascending pathways that cross through the Pons. TRUE/FALSE
FALSE
| Both ascending and descending tracts pass through the pons.
41
Tracts that connect the cerebrum to the cerebellum are here
Pons
42
Coordination of what two parts of the brain lead to coordinated skeletal muscle movement
Cerebrum and cerebellum
43
This has to do with conscious regulation of skeletal muscle movement
Cerebrum
44
Has to do with unconscious coordination of skeletal muscle movement
Cerebellum
45
Nuclei for which CN are located in the pons?
V: trigeminal
VI: abducens
VII: facial
VIII: vestibulocochlear
46
The pneumotaxic respiratory center is located here
Pons
47
Site for NE synthesis and secretion in the pons
Locus ceruleus
48
Locus cereleus is part of what system that has to do with awakeness, alertness, attentiveness.
Reticular activating system (RAS)
49
Midbrain contains the nuclei for what CN?
III: oculomotor
IV: trochlear
50
Nuclei for CN III - XII are all located in what structure?
Brainstem
51
Midbrain is divided into that two structures? (Roof and floor of midbrain)
Tectum (roof)
| Tegmentum (floor)
52
What are the 4 twin bodies located in the tectum of the midbrain?
Corpora quadrigemina
- 2 superior colliculi
- 2 inferior colliculi
53
This part of the corpora quadrigemina receives sound impulses from the inner ear
Inferior colliculi
54
Where does the inferior colliculi send sound impulses after received
Superior colliculi
55
Part of the corpora quadrigemina that is for visual tracking of an object. Uses impulses from eyes, skin and cerebrum.
The 2 superior colliculi
56
Who is an example of someone who has very well developed superior colliculi?
MLB hitter
57
ASCENDING tracts pass through here after passing through the medulla an pons, before they get to the cerebrum.
Tegmentum (floor of midbrain)
58
This is the origin of the rubrospinal tract, has to do with unconscious coordination of movements.
Red nuclei
59
What animal has highly developed red nuclei?
Red nuclei
60
Origin of the nigrostriatal tract, part of the basal nuclei
Substantia Nigra
61
Red nuclei/rubrospinal tract, substantia nigra are located where in the brain?
Tegmentum of the midbrain
62
These are descending tracts that connect the cerebrum to the SC, located in the midbrain.
Cerebral peduncles
63
The nuclei of the RAS are scattered widely throughout the brainstem. TRUE/FALSE
TRUE
64
RAS receives impulses from nerves that innervated the face. (Eyes, skin, ears, nose, etc.) TRUE/FALSE
TRUE
65
These two things make up the medullary respiratory center
Medullary inspiratory center
| Medullary expiratory center
66
Part of control of ventilation in the pons of the brainstem
Pontine pneumotaxic center
67
The cells that compose the medullary insp center SPONTANEOUSLY generate AP or are spontaneously active. TRUE/FALSE
TRUE
68
MIC sends impulse to the phrenic nerve that innervates the ___________ creating longitudinal distance in the lungs.
Diaphragm
69
MIC also synapses with intercostal nerves that innervates ___________ intercostal muscles and pull the ribcage _______ and _______ creating anterior and posterior size of the lungs.
Intercostal nerves activate EXTERNAL intercostal muscles that pull the ribcage UP and OUT.
70
As the size of the lungs increases, the volume of the lungs increases, which INCREASES/DECREASES intrapulmonary pressure
Decreases intrapulmonary pressure
71
When does air enter the lungs?
| When does air movement stop?
When intrapulmonary pressure is less than atmospheric pressure, goes with gradient
Stops when pressure equilibrates.
72
During normal quiet breathing expiration is an active process. TRUE/FALSE
FALSE
It is a passive process
73
The MIC has a collateral axon to the ________ that sends impulses down to MIC to stop sending AP
Pontine pneumotaxic center
74
When MIC is not activated, then diaphragm is no longer activated, so the muscle does what to decrease the longitudinal size of the lungs
Domes up/relaxes
75
MIC not activated, so external intercostals are not active, so they do what to decrease ant/post size of lungs
Pulled down and in
76
As lung size decreases, intrapulmonary pressure DECREASES/INCREASES.
INCREASES
77
When does air exit the lungs, according to pressures?
When intrapulmonary pressure exceeds atmospheric pressure
78
This is ONLY active during a forceful expiration; in the medullary respiratory center.
Medullary expiratory center
Ex) bday candles
79
MEC synapses with the intercostal nerves that innervate the __________ intercostal muscles
Internal intercostal muscles
80
When internal intercostal muscles are activated what happens to the ribs?
Causes what to happen to the size and intrapulmonary pressure?
Pulled further down and further in
which decreases size of the lungs, and increases the intrapulmonary pressure to exert a forceful exp
81
We can increase/decrease ventilation by higher brain centers, just by thinking about it. TRUE/FALSE
TRUE
82
Located in the medulla, they monitor the pH of the CSF; indirectly measures CO2 levels.
Central medullary chemoreceptors
83
An INCREASE/DECREASE in CO2 causes excitation of central medullary chemoreceptors
INCREASE
84
What happens to ventilation and pH when central medullary chemoreceptors are excited?
Increases rate and depth of ventilation, which blows off CO2 and decreases CO2 content and the pH of the CSF and receptors are no longer excited.
85
Where are peripheral chemoreceptors located; primarily monitor the PO2 of blood.
Bifurcation of the carotids and aortic arch
86
What excites peripheral chemoreceptors?
When PO2 gets below ~50-60
87
Peripheral chemoreceptors send a message to the MIC that INCREASES/DECREASES rate and depth of ventilation.
INCREASES
88
This reflex has to do with stretch receptors in the lungs that prevent overinflation of the lungs
Hering-brewer reflex
89
Increased muscle activity and Pain both INCREASE/DECREASE rate/depth of ventilation
INCREASE
90
Largest portion of the diencephalon
Thalamus
91
4 components of the diencephalon
Thalamus
Subthalamus
Epithalamus
Hypothalamus
92
Located between the 2 lobes of the thalamus
3rd ventricle of the brain
93
Why is the thalamus considered the "relay center"?
Where almost all sensory input arrives/stops before information is sent to higher brain centers
94
The thalamus INTERPRETS the sensory input that arrives. TRUE/FALSE.
FALSE
It just tells which area of the brain the sensation should be sent to, it does not interpret it.
95
Located on the thalamus, receive input form CN II (optic) visual pathways before transferred to higher brain centers.
Lateral geniculate bodies
96
Also located on the thalamus, and receive CN VIII (vestibulocochlear) auditory pathways before transferred to higher brain centers
Medial geniculate bodies
97
The thalamus plays a minor role in our UNCONSCIOUS response to pain and suffering. TRUE/FALSE
FALSE.
Plays a MAJOR role in our response to pain and suffering.
98
The subthalamus is one component of the ________ nuclei
Basal nuclei
99
What two structures compose the epithalamus
Habenular nucleus
| Pineal body
100
Receives lots of input from CN I (olefactory) fibers, and lays a role in the limbic system; especially our emotional/visceral gut response to odors.
Habenular nucleus of the epithalamus
101
Where melatonin is secreted from
Pineal body
102
Melatonin is produced during ________ and suppressed during ______. Can be highly associated with ________.
Produced in darkness, suppressed in light.
| Can be associated with depression.
103
Main fxn of the hypothalamus
Regulate the activity of the pituitary gland
104
How is the hyothalamus connected to the pituitary gland?
Infundibulum (stalk)
105
Connects the hypothalamus to the anterior pituitary
Hypothalamohypophyseal portal system
106
Two capillary networks connected by a vein.
Portal system
107
Another name for anterior pituitary
Adenohypophysis
108
Hypothamohypophyseal portal system allows _______ to be transported from hypothalamus to the anterior pituitary to regulate synthesis and secretion of the ant pit ______.
Hormones; hormones
109
Growth hormone releasing hormone produces what hormone from the anterior pituitary
Growth hormone synthesis and secretion
110
Secreted from the hypothalamus and causes inhibition of growth hormone syn/sec from the ant pit
Growth hormone inhibiting hormone or somatostatin
111
Thyroid stimulating hormone releasing hormone = what hormone from the ant pit
Thyroid stimulating hormone synthesis and secretion
112
TSH stimulates receptors in the thyroid to produce what?
T3 and T4
113
Adrenocorticotropic hormone releasing hormone = syn/sec of what hormone in the ant pit
ACTH
114
Where are the primary receptors for ACTH, and what is released from this area.
Adrenal cortex
Primarily cortisol, also aldosterone and some androgens
115
What 2 hormones are syn/sec in response to gonadotrophin releasing hormone from the hypothalamus
Follicle stimulating hormone (FSH)
Luteinizing hormone (LH)
116
Target cell receptors in women for FSH and LH?
Men?
What hormones does it regulate in women/men?
Women: ovaries, regulates estrogen/progesterone
Men: testes, regulates testosterone production
117
Causes synthesis and secretion of prolactin from the ant pit
Prolactin releasing hormone
118
Target cell receptors for prolactin in women is in the _______, and causes milk ________.
Breast
| Milk production
119
Secreted from the hypothalamus and inhibits syn/sec of prolactin from the ant pit
Prolactin inhibiting hormone
120
As the circulating ant pit hormones INCREASE/DECREASE, there is feedback to the hypothalamus to alter its output.
INCREASE
121
How is the hypothalamus connected to the posterior pituitary gland (neurohypophysis)
Hypothamohypophyseal TRACT
122
Axons that originate in the hypothalamus and terminate in the post pit make up the hypothamohypophyseal PORTAL SYSTEM. TRUE/FALSE?
FALSE
| Axons make up the TRACT.
123
The supraoptic and paraventricular nuclei are r.t. The ANT/POST pituitary gland?
Posterior
124
The hormones releases in the post pit are synthesized in the nerve cell bodies in the hypothalamus. TRUE/FALSE.
TRUE
125
Two corresponding post pit hormones that are synthesized in the hypothalamus, travel down axons and are stored in secretory vesicles at the terminal buton in the post pit.
ADH
| Oxytocin
126
What will cause release of ADH and oxytocin?
APs
127
ADH also known as
Vasopressin
128
Vasopressin is released in response to excitation of ___________
Osmoreceptors
129
Where are osmoreceptors located and what do they monitor?
Located in hypothalamus
| Monitor osmolality
130
Normal body fluid osm?
~300 mosm
131
What excites hypothalamic osmoreceptors?
Increase in body fluid osmolality (above ~300)
132
Activated osmoreceptors generates action potentials from what nuclei
Supraoptic and periventricular nuclei
133
The AP released from osmoreceptors go down hypohypo tract and cause release of _______ from post pit.
ADH
134
What are the two receptors for ADH and where are they located? What does activation of these receptors cause
V1: vascular smooth muscle; cause vasoconstriction
V2: found in the kidneys; causes increased water reabsorption from kidneys back to bloodstream
135
Causes uterine contraction and milk expression
Oxytocin
136
Control of HR, vasoconstriction/vasodilation, urination, peristalsis, and others are under autonomic control. These centers have synapses in this structure from higher brain centers.
Hypothalamus
137
Where is the swallowing center, and hunger/satiety centers located?
Hypothalamus
138
If someone were to have a hypothalamic lesion and have uncontrolled shivering/sweating; why is this?
Bc the temperature regulation center is located in the hypothalamus
139
The hypothalamus coordinates the sleep/wake cycle with the __________ system
Reticular activating system (RAS)
140
Precentral gyrus is in the _______ lobes
Frontal lobes
141
Postcentral gyrus is in the ________ lobes
Parietal lobes
142
This lobe is responsible for complex planning of behavior; moderates our personality, decision making, and social behavior
Prefrontal lobe
143
_______ prefrontal dom = highly organized, good at math, linear/logical thinking
Left prefrontal dom
144
__________ prefrontal dominant = musically talented, creative, and artistic
Right prefrontal dominant
145
Play a role in pre-planning/coordinating muscle movement
Premotor area
146
Where descending motor pathways originate
Primary motor cortex on the precentral gyrus
147
The more _______ devoted on the primary motor cortex for that part of the body, the more complex muscle movement occurs there.
More space = more complex movement
148
Left primary motor cortex innervates the right side of the body. TRUE/FALSE.
TRUE
149
Initial planning of muscle movement is in the anterior _______ lobe.
Ant frontal lobe
150
Anterior frontal lobe sends commands to the _______ area
Premotor
151
This decides what muscles to contract, and sends a message to the primary motor cortex according to the motor homunculus
Premotor area
152
The motor homunculus activates those descending motor pathways so that they will end in ________
Skeletal muscle movement
153
Sensory areas are located in the _________ lobes.
Parietal lobes
154
Sensory impulses are sent here for initial interpretation and localization
Primary sensory cortex
155
Impulse from the primary sensory Cortex is sent where?
Sensory association area
156
What does the sensory association area do after receiving an impulse?
Compares current sensation with previous experience
Determines importance of that sensation
Begins process of determining appropriate response
157
If you have a large amount of space devoted to a certain area of the body on the sensory homunculus, that means that there is a greater conc of ___________ in that area of the body.
Greater conc of sensory receptors
158
In both the sensory and motor homunculus, where are the upper/lower areas distributed
Upper body/face on lateral side, lower body on medial portion
159
Sensations form the LEFT side of the body will be transported to the primary sensory cortex on the LEFT side of the brain. TRUE/FALSE
FALSE
| Sensations from left will be transported to the right side of the brain
160
Sensory speech area for understanding/interpreting words; located in parietal lobe.
Wernickes area
161
Occipital lobe is divided into what two things
Primary visual cortex
| Visual association area
162
Where images are initially sent, where image is seen but not yet interpreted or understood
Primary visual cortex
163
Where image is compared with previous experience, importance determined, and transmitted to other parts of the brain for final processing, interpretation and what the response should be
Visual association area
164
When you read words on paper, what is the first step from reading to spoken word?
Image is Projected onto rods and cones of the retina
165
Those image projected onto the rods and cones of the retina activate what pathways?
CN II (optic)
166
After impulse sent through CN II fibers, it is sent to the primary visual cortex where it is _______ but not _______.
Image is seen but not identified (in the primary visual cortex)
167
From the primary visual cortex, the image is sent here, where the image is identified as words.
Visual association area
168
After the the visual association area identifies an image is words, it is sent to what area to be interpreted?
Wernicke's area
169
Which area chooses the individual words and the sequence of those words for a logical thought.
Wernicke's area
170
From wernicke's area, if we are going to speak these words chosen for logical thought, then that information is sent to _________ area to choose the sequence of muscle activity needed to speak the words.
Broca's area
171
From Broca's area (premotor area), the information about what muscles to use to speak chose words is sent to what area ?
Primary motor cortex.
172
From the primary motor cortex, the information about chosen words and the muscles needed to speak them, activated ____________ motor pathways to the muscles used to speak.
Descending motor pathways
173
Where sounds are initially sent, basic processing (pitch, volume)
Primary auditory cortex
174
Compares sound with previous experience with the sound, directs to other parts of the brain for understanding, interpretation and appropriate response
Auditory association area
175
Sound is first transmitted through what CN fibers
CN VIII (vestibulocochlear)
176
From CN VIII pathways, the impulse is sent to the __________ where sound is heard but not yet identified
Primary auditory cortex
177
From the primary auditory cortex, words are sent to the auditory association area where the sound is further processed and identified as a _____.
Word
178
After the auditory association area identifies a sound as a word, where does it sent the impulse, so that the words can be interpreted, and sequence of words chosen in response
Wernike's area
179
What happens to the auditory impulse after the words are interpreted and a response is formulated in the wernicke's area? (All the way to using the muscles to speak them)
Sent to Broca's area (muscle activity planned)
Sent from Broca's to primary motor cortex
Descending motor pathways activated to the muscles used to speak
180
If wernicke's are affected in a stroke, will you have receptive aphasia or expressive aphasia??
Both bc wernicke's are interprets, but its also formulates the sequence of words you speak
181
If you have a lesion in Broca's area, will you have receptive or expressive aphasia?
Expressive aphasia, bc wernicke's is still intact--reception of words and interpretation is not affected
182
In MOST people wernicke's and Broca's are is on the LEFT side of the brain, making L sided strokes more devastating. TRUE/FALSE
TRUE
183
Purpose is to coordinate with the primary motor cortex and premotor areas to prevent unwanted muscular movements
Basal nuclei
184
What 3 structures make up the basal nuclei?
Corpus striatum
Subthalamus nucleus
Substantia nigra
185
The corpus striatum (of the basal nuclei) is made of what two nuclei
Caudate nucleus
| Lentiform nucleus
186
The lentiform nucleus is composed of what two structures
Globus pallidus
| Putnamen
187
The axon from the substantia nigra that synapses with the caudate nucleus is called the ________ tract.
Nigrostriatal tract
188
What NT is released at the synapse of the nigrostriatal tract to the caudate nucleus?
Dopamine
189
Dopamine is EXCITATORY/INHIBITORY to the caudate nucleus
Inhibitory
190
Primary motor cortex also synapses with the caudate nucleus, the NTs here at this synapse are ________.
Are these NTs EXCITATORY/INHIBITORY?
Ach
Glutamate
EXCITATORY
191
Besides the primary motor cortex, what other area of the brain synapses with caudate nucleus and releases Ach and glutamate?
Globus pallidus
192
There has to be a very fine balance between excitatory and inhibitory impulses at the caudate nucleus in order to have smooth, coordinated muscle movement. TRUE/FALSE
TRUE
193
If there was a dopamine deficit or deficiency of dopamine receptors on caudate nucleus, then what would this lead to?
What is a common disease that exhibits this?
Domination of excitatory effects and unwanted muscle movement
Parkinson's
194
Parkinson's symptoms
```
Stooped posture
Pronating/supinating hands
Slow, shuffling gait
Diff speaking
RESTING NON INTENTION TREMORS
```
195
Besides L-dopa, what is a procedure used to treat Parkinson's/essential tremors?
deep brain stimulation (DBS)
196
How many stages are there for DBS surgery?
What are they?
4 stages
Stage I: bone marker placement/MRI scan
Stage II: electrodes implanted
Stage III: generator implant; wire hook-up
Stage IV: activation and programming of DBS
197
What type of anesthesia for Stage I DBS sx? LMA or ETT?
General anesthesia
| LMA tube unless contraindicated
198
During stage I DBS, they put ________ markers on the skull that will be used to attach a large contraption that will help guide wires down into the brain.
Bone markers
199
Why is the MRI scan done in stage I DBS ?
So basal nuclei structures can be identified during sx
200
In stage II, when the electrodes are implanted, the pt undergoes a general anesthesia craniotomy. TRUE/FALSE.
FALSE
| Pt has an AWAKE craniotomy
201
Why are pts taken off their meds for stage II DBS?
So tremors will be at their worst
202
During this stage of DBS, only a small amount of remifentanil is given before local injection and the pt is kept awake for the remainder of the procedure
Stage II
203
What other common medicine must pts be off of in order to complete stage II DBS, that may interfere with their tremors?
BETABLOCKERS
204
Approximately how far apart is each stage of DBS sx?
One week
205
The DBS generator is placed in the ______
Chest
206
DBS generators are good for ______ yrs
5-10 yrs
207
Both the limbic system and the prefrontal lobes play a role in _______
Motivation
208
Part of the limbic system that plays a very large role in converting short term memory to long term memory
Hippocampus
209
We store memories according to our __________ that we experienced when we formed the memory
Emotions
210
When we recall a memory, emotions associated with those memories will return as well. TRUE/FALSE
TRUE
211
Plays role in visceral gut response to odors
Habenula
212
Play a role in human sexuality
Mammillary bodies
213
This connects various parts of the limbic system, so emotions can be spread throughout the brain
Fornix
214
What mental illness is especially linked to abnormalities in the limbic system?
Bipolar
215
Pica is an example of a lesion of the _________
Limbic system
216
You will be more likely to get angry if you have a lesion to your limbic system. TRUE/FALSE
FALSE
| Ppl LOSE their ability to be angry with limbic system abnormality
217
If lesion of limbic system, how do you respond to dangerous stimuli?
You lose the ability to fear dangerous stimuli
218
Regulates skeletal muscle movement at the unconscious level
Cerebellum
| Also basal nuclei
219
The cerebellum does not initiate movement, but contributes to coordination, precision, and accurate timing of movement. TRUE/FALSE
TRUE
220
Receives sensory input from SC and other parts of brain, fine-tunes motor activity
Cerebellum
221
This informs the cerebellum of desired muscle movement
Collateral from the descending upper motor neuron
222
Upper motor neuron synapses with lower motor neuron which activates ___________
Skeletal muscle
223
What two structures sense changes in tension on muscle fibers
Muscle spindles
| Golgi tendon bodies
224
Golgi tendon bodies and muscle spindles send _________ info to the _______ by type A alpha fibers about the actual muscle movement.
Proprioceptive information to the cerebellum
225
What two types of information does the cerebellum receive, so that it can compare them.
Information about what the desired muscle movement and what the actual muscle movement is
226
How does the cerebellum let you consciously/unconsciously try to bring about congruence of the desired and actual movement?
Consciously: info back up to brain through thalamus
Unconsciously: extrapyramidal pathway, activates rubrospinal tract
227
Movement disorder associated with cerebellar lesions
Intention tremors
228
Test for cerebellar lesion? Does positive or negative indicated a lesion?
Romberg test
| Positive indicates lesion
229
Membranes that surround the brain, protect the brain and anchor the brain in place
Meninges
230
Meninges surround the brain and the ________
Spinal cord
231
The meninges of the brain are __________ with the meninges around the SC
Continuous
232
This is the layer just below the skull
Dura mater
233
The dura mater is composed of ______ layers
2 layers
234
When the two layers of the dura mater separate it forms what?
Dural venous sinuses
235
What is in the dural venous sinuses
CSF
| Venous blood
236
The __________ sinus runs along the entire length of the longitudinal fissure
Superior sagittal sinus
237
This type of bleed is just above the dura mater and just beneath the skull
Epidural bleed
238
Potential space below the dura mater, lined with thin film of fluid
Subdural space
239
Meninge around the brain composed of lots of tiny, fragile blood vessels. (Spider web like appearance)
Arachnoid mater
240
Since blood vessels of arachnoid mater are very thin and fragile, they bleed easily and can lead to what?
Subarachnoid hemorrhage
241
What is in the subarachnoid space around the brain and SC?
CSF
242
This layer is inseparable from the brain, attached directly to the brain.
Pia mater
243
This dural venous sinus sits right above the corpus collosum
Inferior sagittal sinus
244
Infolding of the dura mater that separates the L and R cerebral hemisphere
Falx cerebri
245
Infolding of dura mater that runs between L and R cerebellar hemispheres
Falx cerebelli
246
Infolding of dura mater between cerebrum and cerebellum
Tentorium cerebelli
247
Opening in the dura mater to allow passage of the brain stem
Tentorial notch
248
A SUPRATENTORIAL/INFRATENTORIAL tumor is more lethal.
Infratentorial tumor is more lethal bc there is less space to grow and very vital structures present
249
What is the difference in the dura mater of the brain and the dura mater of the SC? (2)
Dura mater around the SC is only one layer, instead of two.
Definite space between the dura mater and the vertebral column (epidural space: meds given here)
250
The corroid plexuses are made up of ________ cells that synthesize the CSF from _________
Ependymal cells
| Plasma
251
These ventricles are located in the medial aspects of the cerebral hemispheres, right below the corpus collosum
Lateral ventricles 1&2
252
This passageway allows CSF to move from the later ventricles to the 3rd ventricle
Foramen of Monro (intraventricular foramen)
253
Where is the 3rd ventricle located
In between the 2 lobes of the thalamus
254
What passageway allows CSF to move from the 3rd ventricle to the 4th?
Aqueduct of sylvius (cerebral aqueduct)
255
The 4th ventricle is continuous with the ________ that allows CSF to flow the length of the SC.
Central Canal of the SC
256
What is the only normal way that CSF can move from the ventricular system into the subarachnoid space around the brain and SC?
The 3 openings (foramina) in the 4th ventricle
257
The CSF production remains constant regardless of the volume and pressure within the ventricular system and subarachnoid space. TRUE/FALSE
TRUE
258
What causes hydrocephalus?
Accumulation of CSF
259
Hydrocephalus due to a problem/obstruction within the ventricular system
Noncommunicating hydrocephalus
260
Hydrocephalus when CSF gets to subarachnoid space but cannot be reabsorbed
Communicating hydrocephalus
261
Projections from subarachnoid space into venous sinuses that allow for one way flow of CSF into venous sinuses
Arachnoid granulations
262
Obstruction of ________ can lead to communicating hydrocephalus
Arachnoid granulations
263
Which ventricles have the largest corroid plexuses and produce the most CSF?
Lateral ventricles
264
Movement of CSF/blood from dural venous sinuses to R heart
```
Empty into internal jugulars
Jugular foramen
Subclavian
Superior vena cava
R heart
```
265
Total amount of CSF is ~ 150ml, how much is in the ventricles and subarachnoid space?
Ventricles ~ 23 ml
| Subarachnoid space ~ 127ml
266
CSF pressure (supine)
50-100 mm H2O
267
About how much CSF do we produce each day? Reabsorption is about the same.
~500-750 ml
268
What 3 electrolytes are more abundant in the CSF?
Sodium
Magnesium
Chloride
269
CSF should be completely clear and colorless. TRUE/FALSE.
TRUE
270
3 branches of the aorta in order
Brachiocephalic
Left common carotid
Left subclavian
271
Brachiocephalic artery divides into what two arteries
R Common carotid
| R subclavian
272
R/L common carotids bifurcate into what arteries
Internal/external carotids
273
R/L subclavian Arteries branch off to make what arteries that carry blood to the brain?
R/L vertebral arteries
274
What are the 4 arteries supplying blood to the brain?
R/L internal/external carotids
| R/L vertebral arteries
275
Internal/external carotids pass through _______ to get to the base of the Brain
Carotid canal
276
How do the vertebral arteries get blood to the base of the brain
Foramina of the Transverse processes of the cervical vertebra
277
Where do the Middle cerebral arteries (internal carotids) provide blood flow to?
Lateral frontal lobes
Lateral parietal lobes
Part of temporal lobes
278
Anterior cerebral arteries supply blood flow to what areas of the brain?
Prefrontal lobes
Medial frontal lobes
Medial parietal lobes
279
Vertebral arteries form to make the _______ artery when they get to the brain
Basilar artery
280
Provides bloodflow to the brainstem and Pons
Pontine arteries coming off of basilar artery
281
Supply blood flow to the occipital lobes and much of the temporal lobes
Posterior cerebral arteries
282
The anterior/posterior communicating arteries connect the cerebral arteries to each other and form what structure that allows blood to be diverted around obstructions, so brain is still perfused.
Circle of Willis
283
What anatomic structures passes right through the circle of Willis ?
Optic Chiasm
| Infundibulum (that connects hypothalamus and pituitary)
284
3 main volumes in the intracranial vault
Brain tissue
Blood
CSF
285
Abnormal volumes in the intracranial space
Tumor
Cancer
Water
Hemorrhage
286
Increase of volume in one compartment of the brain must be compensated by decrease in volume of another compartment in order for total brain volume to remain fixed and ICP unchanged
Monro-Kellie doctrine
287
What can be displaced the easiest out of all the normal volumes in the intracranial space
CSF
288
The cranial vault has unlimited ability to compensate for increased ICP. TRUE/FALSE
FALSE
| Has very limited ability to compensate, fixed compartment
289
___ ml IC volume means normal IC volume
0 ml
290
Normal ICP ______ mmhg
~5-15 mmHg
291
ICP rises dramatically with each ml of volume starting @ _____ ml
5 mL
292
The brain eats up about ______% of the oxygen delivered through out the body
~20%
293
The brain MUST have continuous _________ to meet oxygen and glucose needs
Blood flow
294
Explain coupling of CBF
If one part of the brain is more active, vessels will dilate to improve blood flow to that area, blood will be diverted from areas not as active
295
Despite changes in BP, CBF remains relatively constant, what is this called?
Autoregulation
296
CPP equation?
| Normal CPP ~_____
MAP - ICP
| Normal ~ 50-70
297
If have a stroke pt, INCREASING/DECREASING blood pressure will maintain CPP in the face of increasing ICP
Increasing BP (MAP)
298
Increased CO2 vasoconstricts cerebral blood vessels and decreases ICP. TRUE/FALSE
FALSE
| Increases CO2 vasodilates and increases ICP
299
If PaO2 decreases below ~________, vasodilation occurs to increase CBF
50-60
300
Why do trauma pts need ICP monitored closely
Loss of autoregulation with severe brain injury
301
FAST/SLOW growing brain tumors have more time to compensate and are LESS fatal
Slow growing brain tumors
302
How can we decrease in IC volume? (4)
Hyperventilate
Osmotic diuretic (mannitol)
Lumbar drain
Positioning: reverse T
