Week 1 Flashcards
1
Q
Epidural space -
Subdural space -
Subarachnoid space -
- which are POTENTIAL?
- which as FLUID?
A
- Epidural space - potential space between bone and dura
- Subdural space - potential space between dura and arachnoid
- Subarachnoid space - fluid filled space between arachnoid and pia
2
Q
*Describe the location of major divisions of the central nervous system, and lobes of the cerebral cortex.
- cerebrum = name the lobes
- diencephalon =
- brain stem =
- cerebellum =
*what is “included” in each?
A
- CEREBRUM = w/lobes (frontal, temporal, parietal, occipital)
- DI = includes thalamus and hypothalamus
- BS = midbrain, pons and medulla oblongotta
- CEREBELLUM (orignates from same part as pons?_
3
Q
- Identify the three layers of meninges
- where is CSF
- where can hematoma happen
A
-MENINGES = skull»_space; epidural»_space; DURA»_space; subdural»_space; ARACHNOID»_space; subarachnoid»_space; PIA
- CSF in subarachnoid space
- hematoma in subdural or epidural space (potential spaces)
4
Q
- Secondary brain injury, intracranial pressure, and the anatomy of brain herniation.
- Identify and locate the ventricles. Use your knowledge of the ventricles to identify neighboring brain regions and brain nuclei.
- Explain the formation, circulation, and absorption of CSF (cerebrospinal fluid) through the ventricles and in relation to the three meningeal layers.
A
-petus LOS
5
Q
____ (epidural, subdural, subarachnoid) hematomas often follow blow to skull (ex -baseball bat) and involves rapid bleeding of arteries
______ hematomas follow more serious brain injurty where brain is “shaken” like in wreck or fall, and invovles bleeding out of veins
**in which is high pressure and which is “low pressure” hematomaa?
A
- epidural - HIGH pressure, arteries between bone and dura, rapid bleeding
- subdural - low pressure, veins between brain and dura, slower progression
6
Q
-epidural hematoma can damage ______ artery between temporal lobes and can lead to _______(delayed or immediate) neurological symptoms
A
- artery along temporal lobe running along meninges = MIDDLE MENINGEAL ARTERY (MMA!!)
- high pressure bleed, but rapid decompresion»_space; so inititally may “shake it off” but get DELAYED NEUROLOGICAL SYMPTOMS
7
Q
Tonsillar herniation = herniation of _______(part of brain) that applies pressure on the _____ part of brain involving the respiratory center.
A
cerebellum herniation»_space; pushing against MEDULLA OBLONGATA (right at level fo foramen magnum = where respiratory centers found)
8
Q
_____ herniation from ICP leads to CNIII compression
A
-UNCAL/TENTORIAL HERNIATION = pushes on CNIII»_space; pupil are DILATED and NON-RESPONSIVE (autonomic 1st thingto go)
9
Q
T/F - epidural and subdurla hematomas BOTH associated with intracranial pressure (ICP)
A
TRUE
10
Q
ICP can push the ____ through the _____ leading to respiratory arrest
A
CEREBELLAR TONSIL through FORAMEN MAGNUM (right at level of MO where respiratory center is)
11
Q
-patient comes in after falling down the stairs, MRI shows cerebellar tonsil herniation and UNCUS (which is medial part of _____ lobe) pushing through the ______ compression CNIII
**if shine light into eyes what would we expect? why?
A
- TEMPORAL lobes through TENORIUM CEREBELLI
- compresses CNIII»_space; pupils remain DILATED! (LOSS of PARASYMPATHETIC constriction) = unopposed sympathetic dilation
12
Q
***Ventricle and CSF flow! make chart !
- what is the order of flow of flow?
- where is CSF MADE?
- what part of brain is each ventricle associated with?
A
–CSF made in R/L (2!) LATERAL VENTRICLES**
» 3rd VENTRICLE** (only 1, between L and R dienceph)
» CEREBRAL AQUEDUCT (midbraiun)
» 4th VENTRICLE** (pons rostally, MO costally and cerebeullum)
» CENTRAL CANAL (spinal cord)
*L>3>Aq>4>C
**CSF made in lateral, III and IV = all have choroid plexus
13
Q
what are the lateral and median aperatures
A
*where CSF flows from the central canal (near spinal cord) out into to subarachnodi space via lateral and medial APERATURES
14
Q
what brain region is each near:
- 3rd ventricle
- 4th ventricle (3)
- cerebral aqureduct
- lateral ventricle
- central canal
A
- 3rd = diencephalon
- 4th = pons, MO, cerebeluum
- CA = midbrain
- LV (#1) = CEREBRUM
- CC = spinal cord
15
Q
_____seperates L and R lateral ventricles
A
septum pellucidum
16
Q
where/how is CSF made???
A
- any of the venrtricle that have “ventricle” as part of name = lateral, 3 and 4
- made in the CHOROID PLEXUS choroid vasculutre
17
Q
-what is choroid plexus??
A
- where CSF is made!
- present in lateral, 3rd and 4th ventricles
18
Q
- how is CSF reabsorbed?
- by ______ which project into the _____ sinus
- decreased reabsorption can lead to ________
A
via projections (arachnoid granulations or “villi”) into the SUPERIOR SAGITTAL SINUS
-decreased reabsorption (ex - by menigngitis) can lead to HYDROCEPHALUS (gradulaly increased ICP) also caused by too much production
19
Q
cerebral cortex vs white matter
A
cortex = surface (usually gray matter on surface, where bodies are, unlike in SC)
20
Q
what would you hit and what would be symptoms if 1cm stick into insular cortex ?
A
Basal gangli = circuit of nuclei like caudate, putamen etc
-1 cm - probably PUTAMEN»_space; involved in movement disorders (parkinsons etc)
21
Q
3 parts of basal ganglia
A
- caudate
- putamen
- globus pallidus
22
Q
***discuss primary sensory vs. primary motor vs association areas
- primary receives information via the ______ (thalmus or hypothalamus)
- T/F - primary and association areas are NOT always found beside each other
- 1st stop is ____(sensory/motor) while last stop is _____(sensory/motor)
A
- may stop at thalamus!
- but 1st stop = PRIMARY SENSORY (put information together from receptors/organs via the THALAMUS to “interpret” in the association cortex)
- FALSE - have association cortex for every sense (visual etc) that is located right beside the PRIMARY cortex
-last stop = PRIMARY MOTOR CORTEX
23
Q
***locate primary motor, somatosensory, visual and auditory cortexes?
- what are pre and postcentral gyrus??
- what is central sulcus?
A
–primary motor cortex (aka pre-central gyrus = in FRONT Of central sulcus)
–primary somatosensory (aka post-central gyrus = BEHIND central sulcus )
–primary visual = way back in occipital
–primary auditory = in temporal lobe
24
Q
what is multimodal association cortex do? how does it differ from association cortex?
A
ASSOCIATION = combine multiple primary signals (sound and smell for ex)
MULTI = receives from association cortex of several sensory modalities.»_space; This area can integrate learning and memory for, comprehension, and integration with past experiences- context.
E.g.. I recognize the sound of the fire alarm, but I smell no smoke and Jill, the fire marshal for this floor, is taking time to check facebook on her way out. Must be a drill. Don’t worry about it.
25
what primary cortex (somatosensory, motor, visual, auditory) found in ....
- in parietal lobe
- in temporal lobe
- in occipital lobe
- in frontal lobe
- parietal (right behind central sulcus) = SOMATOSENSORY
- temporal = AUDITORY
- occipital = VISION
- frontal = MOTOR
26
somatosenssory, auditory and visual cortex are found _____(behind, above, below) their primary cortex
- SS and auditory found right behind primary
| - visual associaiton found right in front of
27
_____ cortex is found on the roof of the lateral sulcus near the base of the precentral gyrus. FXN?
_______ cortex is found within the lateral sulcus between p/f/t lobes and contains part of cortical representation for TASTE, some PAIN processing and EQUILIBRIUM
- primary gustatory cortex = found on roof of lateral sulcus near base of pre-central (motor) gyrus = AWARENESS OF TASTE STIMULI
- INSULAR (5th lobe)
28
where would image recognition/identification take place (primary, occipital asssociation or higher visual)
```
primary = elements (points, lines etc)
assoc = basic image formation
higher = identification
```
29
if you couldn't move right leg, it could be a problem in your ______(left or right) _______(pre or post) central gyrus
-left pre-central
30
premotor cortex is located _____(in relation to pre-central/motor cortex) and does what?
* is located anterior to the precentral gyrus
* Receives processed sensory information used to plan and coordinate complex movement
* Controls voluntary actions dependent on sensory feedback
31
brocas / wernicke's area
-in ______(right, left or both) cerebral hemispheres in ____lobe
_____ involved in expressive aphasia while ______ invovled in receptive aphasia
- BROCA = EXPRESSIVE/MOTOR language ... in dominant side (L>R) cerebral hemisphere in FRONTAL lobe (right in front of pre-motor) >> speech production (connected to Wernicke's language area behind it)
- WERNICKE = RECEPTIVE/PERCENTIVE language in dominant hemisphere (L>R) in posterior part of superior temporal gyrus (BACK/UPPER TEMPORAL)
* Note - right handed individuals = L-dominant hemispehre
32
put the following in order from sensory input to motor output : Spinal cord, thalamus , basal ganglia, cerebellum, primary / association sensory/motor
T/F - primary sensosory and primary motor cortex come "before" associaiton cortex?
-spinal cord >> THALAMUS >> primary sensory >> sensory association >> multimodal >> PRE-MOTOR cortex (+/- CEREBELLUM) >> primary motor cortex (+/- communicate with BASAL GANG and BELL)
FALSE - primary motor comes after, but primary sensory before
33
if you can't. feel your right foot problem. _______ ((area of brain) if can't. move your right foot problem _________
feel = left post-central gyrus (primary SS cortex)) in middle
move =. left pre-central gyrus near. middle
*foot area (homonculus) = dips down between the cemisphere lobes
34
T/F - majority of left and right handed people are left hemisphere dominant for language (ie - bcas area will. be on. left for majority. of ALL people))
TRUE!! about 99.9% of R handed ppl are L-brain dominant; and about 75%of L. handed ppl are. L-dominant
35
damage to wernicke's area would cause _______
inability to UNDERSTAND language (receptive aphasia) ... but also makes it hard to produce large/ advanced communication (can't program the language that we are putting out)
*there icommuncation bewten broca (expressive) and wernicke (perceptiv)
36
describe somatotrphic mapping in the cerebral hemispheres. in a coronal. section (what part of brain controls/feels leg /foot /face etc)
imagine brain cross section --> lay body across withFOOT. dipping down BETWEEN hemisphres and. the face laying on the side
so foot (12'ocklock) >>. leg ((1) >>> trunk (2) >>> arm/hand (2))) >> face (3'oclock)
37
relation between putamen and globus pallidus and caudate nucleus (BASAL GANG!!)
-right under the corpus callosum you would find _______ ((entricle) and underneath that is the _____ (putamen, thalamus, hypothalamus, mammary?)
PUTAMEN = just. 1 cm. inside the insula / lateral. sulcus (like on the side of. brain)
GLOBUS PALL = medial/deep to putamen
CAUDATE = swirles around the putamen like a snake (so. part is above and part is below)
under the CC = LATERAL VENTRICLE .... under that = thalamus (2. lobes right in the middle of brain)
38
*if stroke patient can't move their right foot, the most likely artery blocked in the circile of willis would be _______(posterior cerebral, middle cerebral, anterior cerebral, internal caroti?)
* *which arteries (post,middle, anterior) supplies::
- -occipital. lobe
- -lateral side of frontal lobe
ANTERIOR CEREBRAL!!! = supplies middle part of front half of brain
MIDDLE CEREBRAL = supplies lateral surface of brain (part. of frontal. and temporal. and parietal)
POSTERIOR cerberal = supplies lateral and medial back of brain (OCCIPITAL!).
39
white matter=?
gray matter =?
*where is each found on cerebrum vs spinal cord
- white matter = myelinated axons/tracts (periphery of SC, middle of cerebrum)
- gray= nuclei (periphery on cerebrum, middle of SC)
40
- -internal carotid artery branches into ___ and ____ arteries
- -vertebral converge to become _____ which has ____, ____ and _____ arteries splitting of it
--____communicating artery is most anomalous
--IC >> middle cerebral + anterior cerebral( 2 splits)
--vertebral >> basilar >> anterior inferior cerebellar + superior cerebellar + posterior cerebral (3 SPLITS)
--posterior communication very variable ... can be non-existent or bigger on one side than the other
41
where is cerebral aqueduct found (diencephalon, midbrain, pons or medulla)
midbrain
42
medulla to spinal cord transition demarcated by _____
foramen magnum (at skull base)
43
***postal to 4th ventricle is _____ while caudal to 4th ventricle is _____
rostal (in front) = PONS
| caudal (behind) = CEREBELLUM
44
--cerebral peduncle on the ____(ventral/dorsal) side of brain stem at the level of _______(mid, pons, medulla)
--cereBELLar peduncles on the ____(ventral/dorsal) ______(midbrain, pons or medulla)
*FXNS?
--ventral side of MIDBRAIN ! (aka crux cerebra = motor/sensory highways to and from cerebrum)
--dorsal PONS (has superior/middle/inferior parts... superior= output motor from bell; middle=input from cerebrum; inferior = input from SC)
45
only cranial nerve that exits posteriorly on BS is the ______
T/F - this is also the only cranial nerve that crosses (so damage to R side would result in loss of L fxn)
4th cranial nerve
TRUE
46
_______(rostal or caudal) medulla is higher/above
-where is obey
```
rostal = above (where obex is)
caudal = below
```
47
match midbrain, pons and medulla...
with: mesencephalon, mysencephalon, metencephalon
S > T > Y (alphabetical order moving DOWN)
| mid> pons> med
48
substantia nigra and red nucleus found at ______(part of BS)
midbrain
49
corticospinal tracts and middle cerebellar peducnles found at level of _____(in BS)
pons
50
--inferior olive and medullary pyramids found at ______ level of BS
--what tract crosses within the medullar pyramids
ROSTAL MEDULLA (note - inferior olive = thing that looks like brain within a brain)
--medullary pyramids = where corticospinal tracts cross (fine motor/reflexes)
51
CN 12 (hypoglossal) nucleus found at _____ level of BS
trigeminal nucleus and tract found at level of _______
12 = rostal open medulla
5 = caudal closed medulla
52
axons show up ______ (light or dark) while cell bodies show up _______ in cross-sxn stains
*would cerebellar peduncles be dark or light?
myelinated aons = DARK 9ex - peduncles)
bodies = pale
53
what is tegmentum?
houses all of the cranial nerve nuclei
54
_______forms roof and wall/ posterior surface of brainstem
TECTUM
55
- -where are superior colliculus and inferior colliculus found?
- -roles? (not LO?)
DORSAL MIDBRAIN (quadrigeminal plate) = 4 boobies
- -SUPERIOR colliculus – important in EYE movements and body position
- -INFERIOR colliculus – important in AUDITORY pathway
56
* *are each motor or sensory and where do they cross:
- -corticobulbar
- -spinothalamic
- -corticospinal
- -medial lemniscus
- -CB = CN motor (non-ocular) start in cortex >> exit either at PONS or MEDULLA BILATERALLY)
- -ST = pain/temp sensory >> crosses @ SC
- -CS = fine motor >> lateral tract crosses @ caudal medulla (in pyr); anterior tract crosses @ SC
- -ML = fine sensory >> crosses @ caudal medulla
57
_______ tract lesion would result in loss of fine voluntary movements, spasticity, brisk/pathologic reflexes
PATH: starts in cerebral cortex >> goes through PLIC >_____ (in midbrain) > _____ (in pons) > _____(in medulla) then travels down ______(lateral/medial) SC >> through _____(anterior or dorsal) horn of SC
***where does it cross!
--corticospinal / pyramidal tracts (VOLUNTARY/FINE MOTOR)
cerberal cortex >> PLIC (post limb of internal capsule) >> MEDIAL BS = cerebral peduncles >> basis pointis (pons) >> pyramid (cross) >> LATERAL SC >> anterior horn of SC
*Note - efferent pathway are MEDIAL in MEDULLA, but lateral in SC
***crosses in caudal medulla (in pyramids) ***
58
--difference between lateral and anterior CS tract (what controls axial vs. limbs)
--where does each cross
lateral CS tract - moto distal muscle /limbs ...crosses at pyramid
anterior CS tract - motor axial muscles, coordination ...crosses at level of SC
59
--corticobulbar tracts are _____(motor or sensory) involved in _____
T/F- most have bilateral input (ie, damage to tract will cause LOF/LOS (loss of fxn/sensory) on both sides?)
MOTOR NON-OCULAR CRANIAL NERVES 5,7 (pons) 11,12 (medulla)
TRUE
60
_________ tract carries innervates nuclei of CN 5,7,11 and 12 and passes through the genu of the internal capsule and ______ part of the cerebral peduncle of the midbrain
corticobulbar tract - via MEDIAL part of CP
61
exceptions to bilateral input in corticobulbar tracts (3)
Bilateral input to most nuclei (remember - CB tract innervates CN V, VII, XI, and XII):
- -CN VII innervation of lower facial muscles CL
- -CN XI SCM is IL but trapezius CL
- -CN XII to genioglossus mostly CL
62
dorsal column/medial lemniscus pathway involved _______ and is a ______(2,3) neuron pathway
SENSORY = light tough, 2 point disrimination, joint position (proprioceptioN)
3!! DRG >>> cuneate(arm)/gracile(leg) nuclei >> VPL thalamus
63
describe dorsal column/medial lemniscus pathway (where are the synapses - UPPER CASE)
- where does it cross ?
- dorsal column lies _____(laterally or medially) in the tegmentum
DRG (#1) → dorsal column of spinal cord → CUNEATE (arm) or GRACILE (leg) nuclei (#2) → internal arcuate fibers (cross in caudal medulla) → medial lemniscus (rostral medulla to midbrain) → VPL thalamus → sensory cortex
**MEDIAL! (at most levels)
64
***spinothalamic tracts are _____(lateral or medial) in tegmentum while dorsal column pathway lies _____(laterally or medially)
```
ST = lateral
DC = medially
```
*so lateral injury >> CL loss of pain/temp; medial injury >> CL loss of touch/proprioception
65
spinothalamic tract fxn? where are the synapses/nuclei?
- pain and temperature sensation
| - 3 neuron (DRG >> dorsal horn >> VPL thalamus)
66
* **what asc/desc tracts are responsible for:
- -pain and temperature
- -2 point discrimptation
- -movement of trapexius
- -movement of tongue
- -voluntary movements of limbs
- -spinothalamic
- -dorsal column/medial lemniscus
- -corticobulbar tract (XI)
- -corticobulbar tract (XII)
- -corticospinal tract
67
what are the motor CN's :
- motor only
- mixed?
- motor only = CN 3, 4, 6, 11, 12
| - mixed = 5, 7, 9 and 10
68
CN nuclei organization in BS cross section ...
- -efferents are ______(medial/lateral)
- -afferents are _______(medial/lateral)
```
efferent= medial
afferent = lateral
```
69
CN3, 4 and 6
- innervate ______
- loss of each would lead to loss of _____ eye movement
6 >> lateral rectus - pulls eye OUT
4 >> superior oblique >> look DOWN when adducted
3 >> super/inferior recuts (UP and DOWN), medial rectus (side) and inferior oblique (loop up when adducted)
70
damage to CN3, 4 and 6 on Left side would result in loss of movement in _____ eye
- left eye for 3 and 6
| - right eye for 4 (CROSSED!)
71
medial longitudinal fasciulis does ____
communicates between GSE nerves of eye (3,4 and 6) so that eyes can move together
*very medial
72
if tongue is deviated to the left... damage to CN12 on _____ side
LEFT! points to direction of damage
73
- if can't chew problem with _____
- if can't smile problem with _____
- if can't raise shoulders agaainst resistance is _____
- if thinsg sound really loud problem with _____
- if can't swallow ______
chew = 5
- smile =7
- raise (TRAP) = 11
- loud, problem with stapedius = 7
- swallow = 10
5,7,9,10,11 = special visceral efferent
74
nystgmus and ataxia are chx of _____(lateral or medial) BS injury
LATERAL!!
other lateral tracts = ST (pain/temp), facial sensation (trigeminal)
75
describe GVE and SVE actions of CN11
-where is nucleus located?
General visceral efferent: Ramus internus (cranial portion) at most caudal pt nucleus ambiguus to recurrent laryngeal nerve
Special visceral efferent: Ramus externus (spinal portion) to trapezius and sternocleidomastoid
*Nucleus ambiguous = medulla
76
*Important: autonomic output of BS nuclei = ______(sympathetic or parasympathetic)
PARASYMPATHETIC!!!
ex - so CN3 will CONSTRICT pupil
77
Edinger-Westphal Nucleus (CN__) >> _____(actions/muscles)
EW = 3>> sphincter iris (miosis) and ciliary muscle (accomidation)
78
*action of these GVE neurons?
Superior Salivatory Nucleus (CN____)>>
Inferior salivatory nucleus (CN ___) >>
Dorsal Motor Nucleus of Vagus (CN ___) >>
SSV = 7 >> secretions of lacrimal, submandibular and sublingual
ISV = 9 >> parotid gland, carotid body and sinus
DMN = 10 >> cardiac/pulm/panc plexus >> secretions /paristalsis/bronchial constriction
79
* **what is location of these GVE preganglionic Nuclei:
- 3
- 7
- 9
- 10
```
3 = edinger-westphal @ MEDIAL MIDBRAIN
7 = superior salivary @ PONS
9 = inferior salivary @ MEDULLA
10 = dorsal motor nucleus of vagus @ MEDULLA
```
80
______ cranial nerve involved in taste and carotid baroreceptors
______ CN elevates the pharynx/larynx via stylopharungeus muscle
CN9 - glossopharyngeal for both!
*also involved in pharngeal sensations
81
**eye movement nuclei:
CN6 nucleus located in ______
CN4 located in _____
CN3 located in ________
```
6 = abducens nucleus in PONS
4 = trochlear nucleus in CAUDAL MIDBRAIN
3 = oculomotor nucleus in MIDBRAIN
```
82
where are nuclei found (midbrain, pons or medulla)
- 5 (for mastication)
- 7 (for facial expression)
- 9 (for stylopharyngeus)
- 10 (for soft palate muscles)
5 = trigem motor nucleus @ MID PONS
7 = facial nucelus @ CAUDAL Pons
9 /10 = NUCLEUS AMBIGUOUS in MEDULLA
83
* **nucleus ambiguous
- -in ________ part of BS
- -is home to nuclei of CN _____and ____
- -controls _____(sensory or motor)
- medulla
- 9 and 10
- MMMotor (aMMbiguous)
84
- -cortiospinal tract crosses in ____
- -inability to feel light tough, joint position / 2 point discrimination indicates damage to _________(lateral/medial) tegmentum
- -inability to feel pain indicates damage to _______ tegmentum
CS - crosses in caudal medulla
- tough/proprioception = dorsal column/ML = MEDIALLY
- pain = spinothalmic = LATERALLY
85
sulcus limitans?
-divides efferent(medial) and afferent (lateral) CN nuclei in axial section of SC
86
_____(SVA, GVA) travels via gustatory pathway and distinguishes taste while _____ give sensation from glands
- SVA
| - GVA
87
* *solitary nucleus?
- CN's / fxn (sensory or motor)
- location?
2nd nucleus (in medulla) for 7, 9 and 10 vagal pathways:
- -carry SVA info (TASTE!!) from rostal medulla
- -carry GVA info (larynx, gut distention, baroreceptors) from caudal medulla
**MEDULLA **
*note - solitary TRACT is DARK ... while pale structure around more periphery is nucleus
88
what CN involved in :
____taste of anterior 2/3
_____taste on psterior 1/2
_____epiglottis sensation
-7 = ant 2/3
-9 = post 1/2
10 = epiglottis
89
7,9 and 10 GVA pathways =_______(fxn)
- secondary nucleus = _____
- where?
--7/9/10 GVA = sensation of soft palate, pharynx, larynx etc
- -2nd nucleus = SOLITARY (S=sensory/solitary)
- -on CAUDAL ASPECT of MEDULLA
90
mesencephalic tract nucleus is CN _____ and is involved in _____
CN 5 = unconcscious proprioception (ex - whether mouth is open or closed)
91
-spinal trigeminal tract involves CN _____ (4) involved in _____ (pain or light tough) in face/oral cavity
- CN 5, 7, 9 and 10 (mixers)
| - pain, temp, course touch of face and oral cavity
92
trigeminal lemniscus involved in ______ (touch or pain) while trigeminothalmic invovled in _____ (touch or pain)
*what are the secondary nuclei?
TL = tactile/discriminative touch/pressure (2nd nucleus = principle/main sensory nucleus)
TT = pain/temp of oral cavity (2nd nucleus = spinal trigeminal nucleus)
93
most CN problems are ______(ipsilateral or contralateral)
| -exceptions?
- ipsilateral!
| - exception - CN4!
94
Long tract pathology tends to be ____(contra or ipsilateral)
Corticospinal – crosses in ____
Posterior Column – crosses in _____
Spinothalamic – crosses in ____
Long tract pathology tends to be CONTRALATERAL
Corticospinal – crosses in caudal medulla
Posterior Column – crosses in caudal medulla
Spinothalamic – crosses in spinal cord
95
***recognize clinical signs/features of brainstem injury/pathology
- dec consciousness (decrease reticular activating system)
- nausea/vomitting
- hiccups/respiration
- EYE MOVEMENT PROBLEM (diplopia, gaze paralysis)
- vertigo (8)
- dysarthria (12)
- dysphagia (liquids and solids)
96
brainstem pathology cuasing dysphagia is uasually to ____(Liquids, solids or both)
both
97
3 exceptions to bilateral innervation of corticobulbar motor fibers
Many brainstem motor nuceli (e.g., CN5) have bilateral corticobulbar input. Exceptions include the following
CN7: CL for lower facial muscles
CN 11: Innervation for sternocleidomastoid is IL but for trapezius is CL
CN12: genioglossus is predominately CL (tongue may deviate to side of hemiparesis)
98
eyes looking down and out = _____ problem
CNIII
99
dx? person with head trauma, R eye can't look down when adducted?
dx? when testing eyes, and move YOUR hand to the R... you notice THEIR L eye stays in the center
- L CN IV
| - L CN VI
100
For CN 11, innervatio nfor SCM is _____(IL or CL) and trapezius is _____ (IL or CL)
Ex - if person cant shrug L shoulderr or turn their head to the left, this indicates injury to _____ side
```
SCM = ipsilateral
Trapezius = Contralateral
```
*indicates injury to RIGHT
101
dx? patient has no gag reflex and is hoarse
| dx? patient just has no gag reflex
- gag/swallow/hoarseness = 10
| - gag reflex = 9
102
T/F - crossed signs (ie, some loss of motor/sensory one side and some on other) is sign of cerebral hemisphere pathology not brainstem pathology
FALSE - opposite
BS - is crossed becuase some cross (long tracts) while some don't (most CN)
103
* **localization of problem in brainstem (medial or lateral; left or right):
- -R sided weakness of limbs, R sided loss of fine touch on foot
- -No pain on L side of body
- MEDIALbrainstem (CL loss of CS and ML tracts) on LEFT SIDE
- LATERAL BS injury on RIGHT
104
* **localization of brain stem problem?
- -No pain on R side of body, loss of sensation on L side of face, nystagmus and ataxia
- -No pain on R and no motor on R
--damage to LATERAL BRAINSTEM on LEFT!
*get CL loss of ST tract (pain/temp) and IL loss of facial sensation (trigeminal nuclei and spinal trigeminal tract)
--medial and lateral injury on LEFT (CL loss of ST and CS tracts, respectively)
105
4 motor nuclei in the midline/medial?
- divisors by 12! - 3,4, 6 and 12
| - lateral = 5,7,9,10
106
dx? turning head to left but eyes remain midline
dx? irrigate ear with cold water
**important reflexes to r/o pretty big part of BS**
reflex that has input from 3, 6 and 8 (pretty ibg part of brain stem)
--will see eyes slowly come to eyes that are irrgating then correct cidades ... if normal then big part of BS can be ruled out?
107
CN's that are:
- above pons
- at pons
- below pons (medulla)
- above = 1-4
- pons = 5-8
- medulla = 9-12
108
4 pathways in the midline (start with M) and 4 pathways in lateral side (start with S)
-if cant MOVE right side of body, is BS injury med or lat??
MIDLINE = motor CS tract, medial lemniscus, medial long fasiculus, motor nuclei (3,4,6,12)
LATERAL = spinocerebellar, spinothalmic, sensory nucleus of CN5, sympathetic pathway
*if cant move = corticospinal = MEDIAL
109
lateral medulla damage from _______ artery block
PICA (posterior inferior cerebellar artery) >> loss of pain/temp on ipsilateral side of phase (spinal trigeminal nucleus and tract)
110
**want to do lumbar fxn below ______ (SC level)
```
___# Nerve Root pairs
___ cervical levels
___thoracic levels
___ lumbar levels
___ sacral levels
___coccygeal level
```
L2 = where SC ends!
L3/4 is highest safe level, typically L4/5
```
31 Nerve Root pairs
8 cervical levels
12 thoracic levels
5 lumbar levels
5 sacral levels
1 coccygeal level
```
111
Landmark dermatomes:
C5, C7, T1, T10, L2, L5, S1
```
C5 = shoulder
C7 = middle finger
T1 = armpit
t10 = umbilicus
l2 = hands if in pocket
L5 = wraps around butt down the shins
S1 = back of legs , pinky
```
112
white matter more in ____(lower upper) SC
*distribution as you move up?
more up top ... declines as you go down
113
breathing is controlled by ____(C/T/l/S) spinal cord
CERVICAL - phrenic motor nucleus (breathing
114
large ‘intermediate horn’ found in ____(cervical/thoracic/lumbar) SC level
THORACIC = not much gray matter at all large!
| *‘intermediate horn’ = for sympathetic premotor neurons
115
Large ventral horn chx of _____(cervical/thoracic/lumbar etc SC level) WHY? ... would you expect a lot or a little gray matter at this level
large ventral = LUMBAR (controlling muscles of legs)
-less white matter, more gray matter relative to other levels
116
_____ (cervical/thoracic/lumbar etc) SC level controls sexual function and pelvic control (urination etc) and has ______(more or less) white matter than cervical
SACRAL ! more gray, less white than other levels, pelvic control, parasympathetics
117
sympathetic premotor neurons come out of ____(anterior/dorsal/intermediate) horn @ _____(SC level)
intermediate horn @ thoracic level (very thin butterfly shaped gray matter ... tons of white matter)
118
If patient anterior spinal artery infarct would expect loss of ______ (reflexes, motor strength, sensation, combo?)
- supplies MOST of gray matter of SC (note - long pathways may be ok since axons not as >> complete loss of spinal reflexes and strength!
- sensation ~OK since posterior (supplies part of dorsal horn OK)
119
T/F - posterior spinal artery supplies majority of gray matter in SC
false ... anterior supplies most ... posterior does supply some of dorsal horn (sensation)
120
if person can't move the R side of their body, must be an injury either on L side ______(where?!) or on R side @ _____
can't move R = CS tract (crosses @ medulla)
- - so either L sided brain injury (above medulla pyramids)
- - on R sided SC injury (below
121
gracilis part of ML pathway is ____(lateral or medial) and brings sensory from ____(arms/legs) while cuneate comes up ____ from ____
gracilis = medial from leg (leg touches grass)
cuneate = lateral from arm (comes in laterally, pushing fibers already there to the middle)
122
if can't feel pain on top of R toe...
- must be problem w/ ____tract
- could be injury on ___(L or R) SC @L5
- could be injury on ___(L or R) SC @C2
- could be injury on _____(L or R) of BS
SPINOTHALAMIC = comes in @ SC level (top of foot = L5) .. goes up a few levels then crosses >> contralateral rest of the way up
@ L5 = RIGHT
@C2 = LEFT
@ BS = LEFT
123
*** if pt has "hemisection" injury of R spinal … will get loss of pain/temp of legs on ______ (L or R) and loss of proprioception and discriminatory touch on ______(L or R) side
R-sided injury ...
- loss of pain/temp on L side (ST tract already crossed)
- loss of propio/2pt on R side (DC/ML pathway doesn't cross oil medulla)
124
*** compare stretch vs golgi tendon reflex
- which activates the alpha motor neuron
- which primarily relaxes vs contracts
STRETCH = cause muscle CONTRACTION (ex =pour beer into cup >> activate alpha motor neuron to contract bicep + inhibit counter muscle to relax tricep
GOLGI tendon = cause muscle RELAXATION (protect from damage) ex - lot of force on muscle tendon >> inhibit alpha motor neuron to relax primary muscle + activate counter/antagonistic muscle
125
T/F - golgi tendon reflex doesn't involve alpha motor neuron
T/F - golgi tendon reflex is opposite of stretch reflex
T/F - golgi tendon and stretch reflex BOTH involve simultaneous activation and relaxation of antagonistic muscles
T/F - golgi tendon and reflex are both monosynaptic
FALSE - it inhibits it so primary (strained) muscle relaxes
TRUE
TRUE
??? golgi has an intermediate neuron?
126
draw out golgi tendon reflex (include alpha motor neuron and Ib etc) (NOT LO)
1. excess tension to tendon
2. Golgi tendon organ (sensor) fires along 1b sensory neuron into SC
3. Ib synapses activates 1b inhibitory interneuron
4. inhibitory interneuron inhibits alpha (α) motor neuron to relax strained
The muscle relaxes and excess tension is relieved
127
T/F - deep tendon reflex test the monosynaptic golgi tendon reflex
FALSE ... deep tendon reflex causes muscle CONTRACTION (i.e., its a stretch reflex)
golgi tendon is the OPPOSITE (causes relaxation to prevent damage)
128
problem? ataxic movements, clumsy and slow
cerebellar injury
129
T/F - there is somatotopic organization to both cerebellum and cerebrum
TRUE
130
lesions in _____ part of brain in children causes mutism
CEREBELLAR
131
which is cerebellar NOT involved in:
- coordination of timing of movements
- dampening of movements as reach target
- mutism in adults
- cognition
- eye movements
-mutism in adults (only kids)
132
what are roles for parts of cerebellar
- vermis
- intermediate hemisphere
- lateral hemisphere
- vermis = axial coordination/ataxia,mouth (dysarthria)
- intermediate hemispheres = limb coordintion (fall towards side of problem)
- lateral hemisphere = vertigo (but can be pretty silent - not sure exactly what it does)
eye movements (nystgmus) intermediate?
133
*dentate nucleus found ____
cerebellum (4 of them)
-looks like squigly coral piece we have (on either side of holes in middle of cerebellym)
134
* *3 cerebellar peducncles
- what parts of brain do they communicate with?
- what is largest?
3 cerebellar peduncles:
- bottom - to/from spinal cord (clarks/cuneate)
- middle (largest!) - to/from brain stem PONS (via inf olive)
- top - to/from red nucleus/thalamus/forebrain (via rednucleus/thalamus)
135
- damage to L cerebellum will cause problem on ______
| - commands from R cerebral hemisphere will be processed/modified in _____(L/R) cerebellum
on LEFT! ipsilaterall !!!!
-becuase motor signal from hemisphere crosses on way to bellum
136
T/F - cerebellum simultaneously receives inputs from forebrain and spinal cord
TRUE - in order to manage movement and coordination
137
*describe sensory input to cerebellum from SC?
- what 2 nuclei receive signals from legs vs arms?
- where does it cross on way to cerebellum?
CLARKE's = sensory information from LEGS (similar to gracile nucleus)
-ACCESSORY CUNEATE nucleus = sensory from ARMS
** TRICK - does not ... runs along in dorsolateral tract of spinal cord >> run into cerebullum on SAME SIDE **
138
- palatal myoclonus can result from injury to _____
| - involved in signal from medulla to cerebellum via _____(superior/middle/inferior) peduncle
- inferior olive (motor signal to/from cerebellum)
* Palatal myoclonus is a rapid spasm of the palatal (roof of the mouth) muscles, which results in clicking or popping in the ear. Chronic clonus is often due to lesions of the central tegmental tract (which connects the red nucleus to the ipsilateral inferior olivary nucleus).
- inferior olive important for "TIMING INPUT" so everything stays coordinated (eg - for movement) but also for LEARNING (we think! ... can coordinate the firing of neurons so that can make connections etc)
139
Describe OUTPUT PATHWAY b/w cerebrum and cerebellum (denrate-rubral-thalamic tract)
-what cerebellar peduncle involved?
DENTATE NUCLEUS >> out via SUPERIOR cerebeallar peduncle >> red nucleus >> thalamus >> forebrain
140
* describe cerebellar circuit w/ inferior olive
- sends signal via _____(climbing or mossy) which synapses on ____
- importance?!
**inferior olive >> ascending/CLIMBING fibers >> PURKINJE >> projects into depp cerebellar nuclei >> output to DRT tract
**ONLY OUTPUT from cerbellar cortex and into nuclei cerebellar nucleis
*IO provides mixed timing signals and fire in sync = IMPORTANT FOR COORDINATING AND TIMING MOVEMENTS and motor learning (glossons game)?
141
clarkes' nucleus >> ____ (mossy/climbing) fiber >>> _____ role?!
-CLARKE = input from legs >> sends to MOSSY >> inhibits deep celebar nuclei (via purkinjge) but stimulates parallel pathway fibers
--we don't really know specifics but think its key for motor learning via feed-forward inhibition and model learning
*this pathway in ocmputers helps machine learnings!
142
____(mossy/climbing) fibers = input to cerebellum from clarke's nucleus/cuneate/pontine
______(climbing/mossy) fibers = input from inferior olive nucleus
*remember that only major inhibitor output is from ______ neurons
MOSSY fibers = input to cerebell from SC
CLIMBING fibers = input from inferior olive nucleus (MEDULLA)
*remember that only major inhibitor output is from purkinje neurons .. inhibits DEEP CEREBELLAR NUCLEI
143
the critical part of CEREBELLUM that DAMPENS the approachment tremor (via FEED-FORWARD INHIBITION) is ______
PURKINJE NEURON! (fires via inferior olive, inhibits if from mossy)
144
*cerebellar lesion will affect ____(CL or IL) body
IL (SAME SIDE)
145
***3 main arteries to cerebellum?
- what aspects do they supply?
* what is most common
POST INFERIOR CEREBELLAR ART (PICA) = branch off vertebral >> supplies INFERIOR (back and middle)
ANT INFERIOR (AICA) - supplies just the bottom(around medulla)/front part of cerebell
SUPERIOR - supplies top (will see eyes on image and brain surrounding)
*PICA most common - supplies varying amounts of midline and inferior part ...so clinical manifestation can be variable*
146
clinical presentation of PICA stroke?
- if looking at image the stroke is ____(black or white)
- if L side of cerebellum is white, they would have problems on the ______
STROKE = WHITE
Ex - if L is black, R is white (so L side affected!)
- left side of body clumsy and ataxic
- probably some vertigo
- probably some nystgmus
- truncal ataxia (taking out of vermis)
147
ganglia def?
clusters of peripheral neuronal cell bodies (gray matter of PNS)
148
4 divisions of the PNS?
-where does autonomic system fall into?
*do taste/smell/vision fall into somatic sensory or visceral sensory?
- somatic sensory (general = touch etc; special = hearing, vision)
- visceral sensory (special = TASTE/SMELL)
- somatic motor
- vissceral motor = AUTONOMIC
149
what are:
- exteroceptors
- interceptors
- prioceptors
- nocirepceptors
```
EXTERO = SKIN ... respond to stimuli outside body (touch/pressure temp)
INTERO = VISCERA etc ... from within (stretching ,taste, body temp)
PROPRIO = MUSCLES/JOINTS ... monitor stretch and position
```
NOCI = respond to harfmul stimuli that result in pain
1st 3 = receptors classified by location
4th = classification based on stimulis
150
distinguish (role/location) :
- meissner
- pacian
- ruffini
MEISSNER = LIGHT PRESSURE/TOUCH/VIBRATION (more SUPERFICIAL in hairless skin, genitalia etc)
PACINIAN = DEEP PRESSURE/HIGH FREQUENCY VIBRATION - rapidly adaptive - DEEPER in connective tissue
RUFFINI = DEPP PRESSURE/STRETCH (slowly adaptive) - deep in dermis
151
multipolar vs. bipolar vs unipolar neurons
- primary somatosensory neurons are _____
- most neurons are ______
- neurons in retina and olfactory bulb are _____
- multipolar = lots of dendrites, 1 axons (99%)
- bipolar= two processes; in inner ear (olfactory/retina)
- unipolar = cell body sticks out; short single processs emergencyes from the cell body then divides into 2 long branches ... primary SOMATOSENSORY NEURONS (FOUND IN DRG!)
152
big axons are ______(faster or slower)
- type A vs. B vs. C
- pre vs post ganglionic are type ____
- which are myelinated
FASTER!! ... like vision etc - are fast but also demanding
A = large/fast (fine touch, visual) >>> B (slower but myelenated = pre-gang white rami) >> C (smallest/slowest - unmylinated)
153
myelinated axons, like _____(pre or post ganglionix axons) signals are _____(slower or faster) than unmyelinated
myelinated = pre / type B = faster
unmyelinated = post / type C = slower
154
SCHWANN cells surround _____(myelinated, umyelinated both) axons of the _____(CNS, PNS, both)
- surround myelinated (and unmyelinated?) in the PNS
* Schwann cell cytoplasm is forced from between the membranes. The tight membrane wrappings surrounding the axon form the myelin sheath.
155
_____(roots or rami) are only sensory or only motor
- roots are only S/M
| - rami are mixed
156
lumbar plexus supplies sensory innervation over _______(part of body); sacral supplies ________
```
lumbar = anterior surface of lower limbs (L5 wraps around tho on lateral shin)
sacral = posterior surface
```
bracial = supplies skin
157
brachial plexus is formed by _____(ventral or dorsal) _____(roots or rami) of ________(spinal cord levels)_
ventral rami of C5-T1
158
*fill in with bracial plexus nerves....
______- elbow and wrist, extensors, extrinsic hand extensors
_______ - flexors of elbow
______ - most of wrist flexors, and extrinsic hand flexors, and thenar, lumbricals 1+2
_______ - intrinsic hand + flexor carpi ulnaris, part of flexor digitorum profundus
RADOA:- elbow and wrist, extensors, extrinsic hand extensors
MUSCULOCUTANEOUS - flexors of elbow
MEDIAN - most of wrist flexors, and extrinsic hand flexors, and thenar, lumbricals 1+2
ULNAR - intrinsic hand + flexor carpi ulnaris, part of flexor digitorum profundus
159
ascending nerve damage?
-damage to AXONS - longest affected first so that is why it starts in toes/feet and creeps up
160
* if patient can't feel the front or back of the 5th and 6th digits on L and R arm this signals _____ damage
- what dermatome?
- spinal nerve damage
| - C8 dermatome
161
what nerve:
- abducts/flexes elbow
- flexes elbow
- flexes wrist
- extends elbow
- extends wrist
- abducts/flexes elbow = AXILLAR
- flexes elbow = MC
- flexes wrist = MEDIAN
- extends elbow = RADIAL
- extends wrist = RADIAL
162
*what SC levels associated with brachial plexus nerves?
DX?
- person can't raise arm, stuck rotated medially and supinated ("waiter's tip" arm)
- person with claw hand (can't extend wrist)
3 musc (Musculocutaneous) assisinated (axillary) 5 rats, 5 mice and 2 unicorns (ulnar)
MC = C5-C7
Axillary = C5-C6 (guN = thumb and index!)
Radial / Medial = C5-T1
Ulnar=C8-T1
- waiter arm = ERB's palsy = C5-C6 (damage MC/axillary)
- claw hand = KLUMPKE paralysis = C8-T1 (damage ULNAR)
