pg 1-16 Flashcards
1
Q
gray matter
A
collection of neuron cell bodies
2
Q
nucleus
A
cluster of neuron cell bodies that are morphologically distinct from other neurons
3
Q
lamina
A
layer or band of gray matter=nuclei
4
Q
bodies
A
nuclei, collection of neuronal cell bodies
5
Q
cortex
A
gray matter located on the outer surface
6
Q
white matter
A
an aggregation of neuronal processes/axon/fibers
7
Q
tract
A
collection of neuronal fibers/axons that are anatomically or functionally distinct
8
Q
fasciculus
A
bundle of axon
9
Q
lemniscus
A
ribbon or band of axon
10
Q
funiculus
A
column or cord of white matter
11
Q
what are the divisions of the CNS
A
spinal cord, brainstem, cerebellum, cerebrum
12
Q
brainstem
A
part of the brain that connects the spinal cord to the cerebrum and cerebellum
13
Q
T/F the brainstem includes gray matter regioins
A
true
14
Q
T/F the brainstem includes ascending and descending tracts of fiber
A
true
15
Q
what are the 3 divisions of the brainstem
A
medulla (inferior most), pons (middle), midbrain (superior most)
16
Q
what are the inferior olivary nuclei
A
gray matter area of medulla, pair nuclear complex, landmarks on ventrolateral surface called olives
17
Q
what cranial nerve nuclei are included on the medulla (gray matter)
A
XII, XI, X, IX, VIII, V
18
Q
what white matter areas are included on the medulla
A
pyramids paired, landmark structures on ventral surface, comprised of descending fibers/axons=corticospinal, fibers/axons
19
Q
what are the inferior cerebellar peduncles on the medulla
A
peduncle (stalk or stem), paired structures on dorsal surface that help attach the cerebellum to the medulla, and consists mostly of axons going to and from the cerebellum
20
Q
what are the 2 general features of the Pons
A
dorsal and ventral pons
21
Q
what cranial nuclei are on the dorsal pons
A
VIII, VII, VI, V
22
Q
what is particular to the ventral pons
A
pontine nuclei
23
Q
what is unique about the pontine nuclei
A
receive input from neurons of (ipsilateral) cerebral cortex project, project axons to the contralateral side of cerebellum: these fibers form the middle cerebellar peduncle that connects the pons to the cerebellum
24
Q
what is the cortico-ponto-cerebellar pathway?
A
cerebral cortex->portico-pontine axon->pontine nuclei->ponto-cerebellar axon->fibers of middle cerebellar peduncles->cerebellum
25
what are the general features of the midbrain
most superior part of brainstem, part of the brain ventricular system, cerebral aqueduct (sylvius) divides midbrain into two portions: ventral and dorsal
26
what is unique about the ventral (base) of the midbrain
formed by pair of cerebral peducles (white and gray matter)
27
what is unique about the gray matter of cerebral peduncles of the ventral midbrain?
cranial nerve nuclei: III, IV, part of V. red nucleus, substantia nigra
28
what is unique about the dorsal midbrain?
tectum or roof of midbrain, 2 pair of nuclei (sup & inf colliculi) (neurons of sup colliculi are concerned with coordinating reflexes visual and auditory info, neurons of inf colliculi involved in conscious auditory pathway
29
what is unique about the superior cerebellar peduncles (SCPs)
contain only white matter, attach cerebellum to midbrain and cerebrum
30
what is the cerebral cortex?
most of gray matter is distributed on the outer surface forming cerebellar cortex
31
in the cerebrum, what is the medullary center formed from?
white matter
32
what are the 3 pairs of cerebellar peduncles and what do they connect?
inferior cerebellar peduncles->cerebellum to medulla
middle cerebellar peduncles->cerebellum to pons
superior cerebellar peduncles->cerebellum to midbrain and cerebrum
33
what are the functional features of the cerebellum?
input from most sensory systems and cerebral cortex, influences activity of skeletal muscle (posture, equilibrium, control/ coordination of movement), control of motor activity is largely unconscious
34
what are the two major parts of the cerebrum
diencephalon and telencephalon
35
what separates the two halves of the diencephalon
III ventricle
36
what matter is the diencephalon mostly made up of?
gray matter, with some white
37
what parts of the brain are included in the diencephalon?
thalamus, hypothalamus, epithalamus, subthalamus
38
what is the thalamus
collection of neurons/neuclei that: relay most sensory info to cerebral cortex, involved in motor pathways, influence other brain activity
39
what is the hypothalamus
located beneath the thalamus: principle autonomic center of the brain; helps to control symp and parasymp nervous systems, helps control pituitary gland
40
what is the epithalamus
situated dorsally to thalamus, includes pineal gland
41
what is the subthalamus
under and posterior thalamus, includes subthalamic nucleus involved in motor pathways
42
what is the telencephalon
cerebral hemispheres, right and left separated by longitudinal cerebral fissure
43
how is the gray matter of the telencephalon organized?
cerebral cortex (cortex covers surface of each hemisphere), Corpus striatum (nuclei located deep in each hemisphere, important in motor control functions)
44
what are the three types of fibers that comprise the white matter of the medullary center?
association fibers/axons, commissural fibers, projection fibers
45
what is the function of association fibers/axons?
connect different cortical areas within a single hemisphere
46
what is the function of commissural fibers
connect cortical area of one hemisphere to a (similar) cortical area of the opposite hemisphere, (they decussate, cross, from one hemisphere to the other) example corpus callosum
47
what are projection fibers?
connect an area of cerebral cortex to a subcortical area or subcortical area to cerebral cortical area.
48
what is the area called where projection fibers converge?
internal capsule (positioned deep in each hemisphere)
49
what is the importance of projection fibers?
includes major sensory and motor pathways, sensitive to ischemia, may result in sensory and motor disturbance
50
what is on the surface of the cerebral hemispheres?
folds or gyri
51
what are the grooves that intervene between adjacent gyri?
sulci
52
what are the 5 anatomical lobes of each cerebral hemisphere?
frontal, parietal, temporal, occipital, and insula (island of reil)
53
what is the ventricular system of the brain?
series of fluid-filled spaces within brain that is derived from neural canal of embryonic neural tube
54
what kind of cells line the ventricular system?
ependymal cells
55
what is the choroid plexus?
secretes CSF
56
what does each lateral ventricle consist of?
anterior horn (frontal lobe), body (pre/postcentral gyro), posterior horn (occipital), inferior horn (temporal), collateral trigone
57
what is the III ventricle
unpaired space between the two halves of diencephalon, includes choroid plexus
58
what is the interventricular formina (of monro)
paired, connects each lateral ventricle to the III ventricle
59
what is the IV ventricle
unpaired chamber; includes some of choroid plexus, cerebellum forms the roof, pons and medulla form the floor (rhomboid fossa)
60
what are the lateral apertures?
foramina of lushka, paired, connects IV ventricle to subarachnoid space
61
median apeture
foramen of magendie, unpaired, connects IV ventricle to subarachnoid space (cisterna magna=cerebellomedullary cistern)
62
what is the path of CSF circulation
lateral ventricles-> foramen of Monro-> III ventricle-> cerebral aqueduct-> IV ventricle-> foramina of Lushka and foramen of Magendie-> subarachnoid space (resorption by arachnoid villi)
63
T/F balance between production and resorption is not important
False. it is critically important
64
what is hydrocephalus
excess CSF, results in increased CSF pressure. potential causes: excess secretion, blockage, poor resorption. congenital or acquired
65
what is non-communicating hydrocephalus
blockage of CSF out of ventricles
66
what is communicating hydrocephalus
excess CSF throughout entire ventricular system
67
what is normal pressure hydrocephalus?
abnormal increase in CSF which can cause ventricles to enlarge (idiopathic)
68
caudate nucleus?
nucleus involved in motor control that lies along the lateral ventricle
69
what are the three regions of the caudate nucleus
head of the caudate (lateral wall of anterior horn of lateral ventricle)
body of caudate (lateral wall of body of later ventricle)
tail of caudate (roof of inferior horn of lateral ventricle)
70
what is the amygdala
nuclear complex about the size and shape of an almond, positioned just beyond tip of inferior horn and tail of caudate, part of limbic system
71
what is the hippocampus
gray matter structure involved in processing memory and emotions (limbic system), lies along flood of inferior horn of lateral ventricle
72
what is the fornix
major tract of fibers that originates from hippocampus and projects largely to diencephalon
73
what is the corpus striatum
series of nuclei (gray matter) positioned deep in each hemisphere, involved in motor control
74
what makes up the corpus striatum
caudate nucleus and lenticular nucleus
75
what are the two parts of the lenticular nucleus in the corpus striatum?
globus pallidus (medial), putamen (lateral)
76
what is the internal capsule?
comprised of projection fibers providing connections to and from neurons of cerebral cortex to and from subcortical regions
77
what are the three parts of internal capsule
```
anterior limb (separates head caudate from lenticular nucleus)
genu (between ant and post limbs)
posterior limb (lenticulothalamic portion, between lenticular nucleus and thalamus)
```
78
what is the clinical significance to the internal capsule
damage to internal capsule can lead to sensory and/or motor defects
79
septum pellucidum
thin structure that separates anterior horns of left and right ventricles
80
interthalamic adhesioin
"massa intermedia" gray matter structure physically connects left and right halves of thalamus
81
what vertebral level is the conus medullaris
L1-2
82
the spinal cord enlarges at what segments?
cervical-c4-t1, lumbosacral l2-s3
83
where is the dorsal intermediate sulci present?
t6 and above (positioned between dorsal median sulcus and dorsal lateral sulcus)
84
what are the three divisions of white matter found on the spinal cord
posterior (dorsal) funiculi or columns, lateral funiculi or columns, anterior (ventral) funiculi or columns
85
what borders the porsterior funiculi or columns
D-M sulcus and D-L sulcus
86
what borders the lateral funiculi or columns
D-L sulcus and V-L sulcus
87
what borders the anterior funiculi or columns
V-M fissure and V-L sulcus
88
what is the dorsal lateral tract?
lissauer's tract, present in all cord segments, located at the dorsal lateral sulcus zone, travel 1-2 cord segments up to 4
89
what is the fasciculus gracilis?
extends entire length of cord, below t6 between D-M sulcus and D-L sulcus, above t6 between D-M sulcus and D-I sulcus (major ascending pathway)
90
fasciculus cuneatus
positioned between D-I and D-L sulcus, present T6 and above (major ascending pathway)
91
spinothalamic tract
(anterolateral system) extends entire length of cord, anterolateral part of white matter (major ascending pathway)
92
anterior white commissure?
mostly decussating fibers that contribute to S-T tract
93
Posterior horn of spinal cord
primarily sensory neurons, paired
94
anterior horns of spinal cord
paired, mostly motor neurons
95
what is the intermediate zone of spinal cord
gray matter extends from one side, across midline, to opposite side, includes gray commissure that surrounds central canal, sensory neurons and interneurons
96
lateral horn of spinal cord
extends from T1 to L2-3 cord segments, positioned in lateral part of intermediate zone, comprised of preganglionic sympathetic neurons
97
features of lumbar/sacral cord segments
volume of white matter is low, gray matter high
98
features of thoracic cord levels
volume of white matter is intermediate, gray matter is low
99
cervical cord segments
volume of white matter is greatest, gray matter is high
