CNS/sensory 1 - intro Flashcards
1
Q
name major divisions of the nervous system
A
afferent - sensory input
efferent - motor output
2
Q
describe afferent
A
sensory input
cell bodies outside of CNS
sends axons into CNS
3
Q
which nerves go into cns
A
cranial nerves
spinal nerves
4
Q
describe cranial nerves
A
somatic
visual
olfactory
taste
auditory
vestibular
send into brain directly
5
Q
describe spinal nerves
A
somatic sensation = touch, temp, pain
visceral = sensation inside you - input
send into cns
6
Q
describe efferent
A
motor output
cell bodies in CNS
7
Q
WHAT IS cns
A
brain and spinal cord
8
Q
name efferents
A
somatic efferent
autonomic efferent
enteric
9
Q
describe somatic efferent
A
innervates skeletal muscle
only excitatory - ACH
motor neurons
10
Q
what is ach
A
neurotransmitter at neuromuscular junction
11
Q
describe autonomic efferent
A
innervates interneurons
and attach to other things = smooth and cardiac muscle
excitatory and inhibitory - causes muscles to contract
12
Q
describe enteric
A
nervous system
neurons that control digestive system
13
Q
what is cerebrum
A
cortex
2 halves
outside
14
Q
what is corpus callosum
A
connecting of 2 sides - 2 halves
15
Q
what is thalamus
A
on top of brainstem
16
Q
what is brainstem - parts
A
midbrain
pons
medulla
17
Q
what is frontal lobe
A
motivation
Consciousness
18
Q
what is parietal lobe
A
integrates sensory info from different modalities
19
Q
name 4 lobes of brain
A
frontal
parietal
temporal
occipital
20
Q
what is occipital lobe
A
visal areas
21
Q
what is central sulcus
A
separates primary motor gyrus and primary somatosensory gyrus
22
Q
what is cerebellum
A
below cortex
motor control and movement
23
Q
what is gyrus
A
fold in cerebrum = increased surface area
more cerebral cortex
24
Q
what is sulcus
A
cracks
sulci
25
what are ventricles
little opening called ventricles
produce cerebral spinal fluid
openings/cavities
26
what is gray matter
cell bodies of neuron’s are in 2 mm band on surface
cell bodies
dendrites
synapses
27
what is white matter
myelinated axons
28
what is basal nuclei
basal ganglia
collection of cell bodies all together
29
name divisions of spinal cord
cervical nerves
lumbar nerves
thoracic nerves
sacral nerves
coccygeal nerves
30
how many spinal segments
31
31
what is between vertebrae
spinal nerves
32
what is spinal segment
hockey puck shape
bunch of spinal cord and corresponding 2 spinal nerves coming off on either side
33
describe cervical nerves
8 pairs
spinal nerves innervate = neck, shoulders, arms, hands
34
describe lumbar nerves
lower abdominal wall, hips, legs
35
describe sacral nerves
genitals and lower digestive track
36
what is difference in matter of brain and spinal cord
gray matter on inside of spinal cord
white matter on outside
opposite of brain
37
describe dorsal horn (spinal cord)
wings of butterfly
Afferent
sensory info comes in
behind ventral horn
38
describe ventral horn (spinal cord)
efferents
cell bodies = ventral horn of gray matter
motor info comes out
39
describe gray matter (spinal cord)
neurons form circuitry
butterfly shaped
40
describe central canal (spinal cord)
Opening in middle of gray matter
where csf is
41
describe dorsal root (spinal cord)
afferent
42
describe ventral root
efferent
43
describe white matter (spinal cord)
axons going up and down cord
grouped together in tracts
44
describe dorsal root ganglion (spinal cord)
bulge = cell bodies of neurons that form afferents that send axons into cns
innervates skin and other tissue = as part of somatosensory input
cell bodies located close to spinal cord = in dorsal root or dorsal root ganglion
45
describe cranial nerves - detailed
12 pairs
olfactory and optic nerves - 2 project other places in brain - do not go through brainstem
10 of them project into brainstem
trigeminal nerve innervates face
share both sensory and motor info coming in and out of cranial nerves
46
describe brain edema
increased intercranial pressure pushes brain out base of skull (pushes brain out through only opening)
compresses brain stem and cranial nerves that regulate pupillary response
like how during concussion or head injury = doctor will shine light in eye - looking for pupillary reflex
47
describe early development of the nervous system - up to week 1
fertilized egg - ovum
divides and becomes ball of cells
after one week = blastocyst - week 1 (blastocyst - ball of cells, starts to take shape = hollow cavity on inside)
inner cell mass = inside - bunch of developing cells - eventually becomes you and nervous system
48
describe early development of the nervous system - week 2 and 3 - basic
week 2 - blastocyst = more definition of blastocyst and inner cell mass will grow
week 3 - blastocyst - embryonic disk forms - important layer of cells in blastocyst - neural plate forms
49
describe early development of the nervous system - week 4 - basic
if chop it= look down on embryonic disk --> where specialization starts to form - which cells become nervous system and which cells become everything else
50
describe week 3 of development of neural tube - in detail
3 layers of neural plate - ectoderm, mesoderm, endoderm
neural plate had 2 layers - bunch of cells growing and dividing
starts to form neural groove
51
describe week 4 of development of neural tube - in detail
neural groove starts to form neural tube
Neural crest becomes part of PNS and CNS - part of ectoderm - dorsal root ganglia afferent
sensory input
mesoderm forms dura
neural tube becomes CNS and part of PNS
52
describe neural tube
vesicles develop during week 4 - neural tube forms little bulges
~week 4/5 = forms whole nervous system
53
what does neural tube become
forebrain
midbrain
hindbrain
extension of neural tube = spinal cord
54
describe parts of CNS - from neural tube
fore brain = cerebral hemispheres, thalamus
midbrain = midbrain
hindbrain = cerebellum, pons, medulla
inside neural tube = hollow - cavity becomes ventricles and central canal - csf fluif produced and flows
55
what do ventricles contain
150 ml of cerebral spinal fluid - csf
56
name important ventricles
lateral ventricles
third ventricle
4th ventricle
57
describe lateral ventricles
2 large ventricles - curve around temporal lobes
large
most of csf
58
describe choroid plexus
lining of ventricle
oozes csf into ventricle all the time
59
what are foramens
ventricle connected to each other through little connections
60
describe formation of csf
Produced by the choroid plexus (in the four ventricles, but mainly the two lateral)
rate of 500 ml/day
must leave brain since more than max
61
describe function of csf
supports and cushions cns - specific gravity pf csf and brain are equal
provides nourishment to brain
removes metabolic waste through absorption at the arachnoid villi (organ that takes csf out of brain)
62
describe composition of csf
sterile
colourless
acellular fluid
contains glucose
63
describe circulation of csf - general
passive - not pumped
oozes out of choroid plexus and moves around - absorbed by arachnoid villi
dumped back into venous blood supply
64
what is entire pathway of csf
foramen of munro - where 2 lateral ventricles attach into 3rd ventricle
dump csf into 3rd ventricle (can also produce some csf)
then goes behind midbrain via cerebral aqueduct - midbrain
fourth ventricle (between brainstem and cerebellum) - still produces some csf
central canal - csf flows passively
csf leaves out foramens of lushka (2 lateral) and magendie
csf enters subarachnoid space - now goes outside of brain and spinal cord
cavity collects csf through arachnoid villi - takes out and dumps into venous blood supply (connects at midline)
65
what is subarachnoid space formed by
produced by one of coverings of CSF - meninges aka membranes
66
what is hydrocephalus
too much water in brain - too much csf
csf pushed brain out towards skull
67
name types of hydrocephalus
communicating
non communicating
68
describe communicating hydrocephalus
problem is absorption of csf by arachnoid vili or block in subarachnoid space
but all ventricles are communicating and all foramens ok
69
describe noncommunicating hydrocephalus
problem in ventricle or foramen is blocked
70
what are meninges
membranes
71
what do meninges cover
brain and spinal cord
72
what are 3 meninges of cns and describe
dura mater - protects brain, thick leather
arachnoid membrane - thinner, creates subarachnoid space
pia mater - very thin, lays flat on gray matter
73
what is subarachnoid space = meninges of cns
between arachnoid membrane and pia mater
composed of trabeculae = little foot processes that create space between arachnoid membrane and pia mater
contains csf and blood vessels - dive down and perfuse neural tissu
74
describe dural - venous - sinus
csf returns to blood at dural sinus (dura opens to form this)
csf collected and returned to venous blood supply
arachnoid vili = line dural sinus
csf = subarachnoid space and move into dural sinus via arachnoid villi
75
describe thoracic nerves
down thoracic segments
shoulder, chest
upper abdominal wall
12 pairs
76
how many pairs of coccygeal nerves are there
1 pair
77
what does ectoderm become
pns and cns systems between week 3 and 4
78
what does mesoderm do
Becomes muscles and internal parts of body
79
what does endoderm do
will fold up into tube and form digestive system
80
what happens if neural tube is not formed properly
problem for baby
neural tube deficits
