Lab 3/1 Flashcards
1
Q
midbrain lesions lead to
A
affected gait, PLR, v-lat strabismus, globe rotation, altered state of consciousness
2
Q
cerebellum fx
A
motor execution and error correction
coordination of movement
vestibular fx
3
Q
cerebellar white matter
A
brainstem -> cortex
cerebellar nuclei -> cortex
brainstem -> cerebellar nuc
4
Q
granule cell layer
A
deepest; small tightly packed neurons
5
Q
purkinje cell layer
A
1 cell layer thick btwn granule cell layer and molecular cell layer
6
Q
purkinje cell dendrites
A
into molecular layer; other axons come up perpendicular to those
7
Q
molecular layer
A
mostly made of purkinje cell dendrites and axons projecting to purkinje cells
8
Q
cerebellar input
A
sensory systems and motor programs
9
Q
cerebellar output
A
purkinje cells -> cerebellar nuclei -> UMNs
10
Q
purkinje cells ->
A
cerebellar nuclei -> UMNs
11
Q
cerebellum lives in ____ bounded dorsally by ____
A
lives in cd cr fossa; bounded dorsally by tentorium cerebelli
12
Q
cerebellar lesions will likley
A
also effect cd brainstem unless v small or vascular
13
Q
vestibulocerebellum afferents
A
vestibular via ccp
14
Q
vestibulocerebellum efferents
A
vestibular nuclei via ccp
15
Q
vestibulocerebellum fx
A
- posture
- balance
- VOR
16
Q
vestibulocerebellum incluse
A
floculonodular lobe -> vestibular nuclei -> vestibulocerebellum
17
Q
spoinocerebellum major afferents
A
- spinocerebellar pathways (via CCP)
- cerebral cortex (UMNs and sensory via MCP)
18
Q
spinocerebellum efferents
A
UMNs (via RCP)
19
Q
spinocerebellum fx
A
- real time error correction
- posture
- balance
- tarted limb movements
- locomotion
- postural rxns
20
Q
does cerebellum play a role in menace pathway
A
yes; its the step before synapse on facial nucleus
21
Q
spinocerebellum includes
A
vermis and paravermis and fastigal and interposos nuclei
22
Q
cerebrocerellum
A
planning and regulation of skilled movements
- less developed in domestic animals (lat hemisphere -> dentate nucleus -> motor cortex)
23
Q
cerebellar cortical atrophy histo change
A
dispranized; granule cell layer = less tight and dense = more spread out purkinje cells over it there defining boundary between granular cell or molecular layers
24
Q
general proprioceptive ataxia pathays
A
caused by lesion involving ascending proprioceptive pathways (spinocerebellar pathways, DCML pathways) in spinal cord or brainstem; can have lesion in forebrain but this is much less severe
25
GPA clinical signs
sloppy gait with long sloppy strides, scuffing, can't predict where feet being placed; floating, delayed protraction
26
GPA ipsilateral if lesion in
- spinal cord
- medulla
- pons
27
GPA contralateral if lesion in
forebrain
28
vestibular ataxia seen with lesion in
vestibular apparatus, vestibular nerve, vestibular nuclei, flocularnodular lobe
29
vestibular ataxia clinical signs
wide based stance, short choppy strides, falling over (usually toward side of lesion)
30
cerebellar ataxia occurs with lesion in
cerebellum b/c loss of cerebellar circuits to regulate locomotion through rubrospinal and reticulospinal tracts/ pathways
31
cerebellar ataxia clinical signs
hypermetira, intention tremors, cerebellar lesion can also -> vestibular ataxia
32
wide based stance
can be seen with all 3 types of ataxia but is most pronounced with vestibular ataxia
33
decerebellate rigidity vs decerebrate rigidity
decerebellate rigidity will often have pelvic limbs flexed at hips and the big difference is that there is no mentation difference (ie the patient is wide awake and alert)
34
cerebellar cortical abiotrophy histo change
degeneration of prukinje cells
35
largest commissure connecting left and right side of telencephalon
corpus callous; shiny band of tissue deep within longitudinal fissure
36
what is ventral to corpus callous
fornix
37
fornix is associated with
hypocampal formation (archicortex)
38
lamina terminalis
rostral boundary of diencephalon; separates diencephalon from telencephalon
39
fibers between diencephalon and piriform lobe
fibers of internal capsule
40
optic tract path
moves cdly and dorsally until surrounds and synapses on LGN of thalamus
41
LGN
protrudes laterally from cd diencephalon
42
cd aspect of 3rd ventricle leads to
mesensephalic aquaduct
43
inter ventricular foramina
connects 3rd to lateral ventricles; best way to find this on gross section is to find where choroid plexus of 3rd ventricle courses through foramen on way to lateral ventricles
44
many thalamic nuclei are
relay nuclei bc they relay info from brainstem and basal nuclei to neocortex
45
internal capsule
axons carrying info from thalamus to cortex and axons carrying motor information from cortex to brainstem
46
what thalamic nuclei are grossly evident
medial and lateral geniculate nuclei
47
medial geniculate nuclei fx
relays auditory info to cortex
48
lateral vehicular nuclei fx
relays visual information to cortex
49
how to find LGN
follow optic tract (this will be at end of optic tract just rostral to rostral colliculus)
50
other nuclei in thalamus (other than LGN and MGN) relay
somatosensory, taste, olfaction, vestibular, and motor information to primary cortical areas
51
relay nuclei are located in
lateral thalamus
52
medial thalamus
adjacent to interhalamic adhesion, contains intralaminar nuclei which
53
intralaminar nuclei
part of ARAS and indirect spinothalmic pathway
54
nuclei in hypothalamus control
autonomic output from cd brainstem and spinal cord as well as skeletal muscle for fxs important to homeostasis, behavior patterns associated with emotional expression and reproduction
55
ventral most portion of diencephalon
hypothalamus
56
hypothalamus and wall of ventral portion of 3rd ventricle
hypothalamus is lateral to wall of ventral portion of 3rd ventricle
57
infundibular recess of 3rd ventricle
small extension of 3rd ventricle continues ventral to hypothalamus into infundibulum
58
ventral aspect of brain can see
optic chiasm, pituitary gland, and mammillary bodies
59
optic chiasm relatioship to rostral hypothalamus
optic chiasm is ventral to rostal hypothalamus
60
axons from retina for circadian rhythm
synapse in suprachiasmatic nucleus in hypothalamus
61
mammilary bodies are part of
ventral aspect of cd hypothalamus
62
pituitary gland location
attached to ventral aspect of hypothalamus at infundibulum between optic chiasm and mammillary bodies
63
medial region hypothalamus location
md to columns of fornix
64
lateral region hypothalamus location
lateral to columns of fornix
65
lesions of lateral zone of hypothalamus
can produce coma or other alterations of consciousness, similar to lesions of midbrain by interferingg with ascending reticular activating system
66
lesions of medial zone of hypothalamus
can result in autonomic and endocrine dysfunction
67
subfornical organs location and names
SFO, OVLT, Mediance eminence = circumventricular organs associated with hypothalamus and located in wall of 3rd ventricle
68
subfornical organs fx
detect circulating substances in blood including angiotensin II and other hormones important for homeostasis and/ or allowing for secretion of hormones into the blood
69
telencephalon important strcutures
1. Neocortex
2. Paleocortex
3. Archicortex
4. Sulci and Gyri
5. Corpus callosum
6. Internal capsule
7. Corona radiata
8. Basal nuclei
70
neocortex
occipital, parietal, temporal, and frontal lobes
71
paleocortex
rhinal fissure, piriform lobe, olfactory peduncle. olfactory bulb
72
archicortex
deep to neocortex and paleo cortex; fornix can be seen on half brain
73
primary sensory and motor areas of neocortex recieve
direct input form sensory and motor relay nuclei of thalamus
74
damage to primary sensory areas of cortex
produce specific sensory deficits
75
damage to occipital lobe
deficits in tests requiring visual processing (visual following visual placing, navigating obstacles menage response)
76
damage to somatosensory cortex
in parietal lobe; may cause postural rxn deficits or hypalgesia
77
hypalgesia
decreased pain perception
78
damage to motor cortex
may cause deficits in any fx that requires cortical UMNs including postural rxns, menace response, visual following
79
prefrontal cortex, pts of temporal and parietal lobes involved in
more complex neural processing; damage to these areas may produce behavioral/ personality changes (frontal lobe) and generalized neglect (parietal lobe)
80
parietal lobe is involved in
visuomotor transformations
81
lesions in parietal lobe
can produce deficits in a variety of visually guided behaviors (menace, visual following, visual placing, navigating obstacles)
82
association cortex
regions of neocortex which integrate more diverse types of information to guide behavior (this is in parietal lobe, visuomotor transformations, visualy guided movements)
83
motor cortex location
frontal lobe
84
somatosensory cortex location
frontal / parietal lobe
85
visual cortex locaiton
occipital lobe
86
prefrontal cortex / limbic cortex location
frontal lobe, rostral ot motor cortex
87
hippocampal formation
archicortex; located deep to temporal and piriform lobes; vaguely C shaped
88
amygdala location
amygdala is a basal nucleus; can be seen near ventral tip of hippocampus
89
lateral ventricle
hippocampal formation rolls out will see lateral ventricle which has smooth shinny surface bc of ependymal cells
90
lateral ventricle course
curves ventrally into temporal and piriform lobe
91
fornix made of
axons leaving hippocampal formation which follow curve of hippocampus from temporal lobe to location dorsal to cd diencephalon where they join fibers from fornix on other side
92
body of fornix
where axons course rostrally adjacent to midline dorsal to diencephalon
93
axons from body of fornix
some will continue rostrally dorsal to rostral commissure to synapse on spatial nuclei many of axons in body of fornix curve ventrally cd to rostral commissure forming columns of fornix
94
sepal nuclei
part of basal nuclei axons from body of fornix that continue rostrally dorsal to rostral commissure synapse here; these are coated dorsal and rostral to rostral commissure in septum pellucidum
95
columns of fornix
axons in body of fornix that curve ventrally just cd to rostral commusire form these; columns of fornix then course cdly to synapse in mammillary bodes
96
columns of fornix to mammilary bodies location
slightly lateral to midline so not seen on medial surface of half brain
97
fornix carries
axons from mammillary bodies and septal nuclei back to hippocampus
98
cingulate gyrus
collects information from many cortical areas and projects to hippocampal formation just dorsal to corpus callosum
99
prefrontal cortex
rostral and ventral part of front lobe, plays important role in personality complex behavior and decision making
100
PTN location
medial to LGN and just rostral to rostral colliculus
101
axons in optic tract
course up the lateral aspect of diencephalon and synapse in LGN, pretectal nuclei and rostral colliculus
102
just cr to rostral colliculi transverse apperance
brainstem has characteristic transverse appearance at this level where lateral and cd expansion of diencephalon result in LGN and MGN being located lateral to midbrain
103
sigificant structures associated with somatosensory system dorsal root
```
dorsal roots
fasciulus gracilis
nucleus cuneatus
trigemnial nerve
trigeminal sensory nuclei
3 branches of trigeminal nerve
intraliminar nuclei of thalamus
periaqueductal gray
raphe nuclei
locus coeruleus
brainstem origin of reticular activating system (pontine/ midbrain reticular formation)
```
104
sigificant structures associated with somatosensory system dorsal horn
dorsal horn
fasciculus cuneatus
medial lemniscus
105
sigificant structures associated with somatosensory system dorsal funiculus
dorsal funiculus
nucleus gracilis
somatosensory cortex
trigeminal ganglion
