Neuroanatomy Flashcards
1
Q
what are the roles of the nervous system?
A
- detect changes in external and internal environment.
- relay info and analyse it.
- initiate appropriate responses.
2
Q
how do neurons convey info via?
A
electrical signals.
3
Q
where do afferent neurons from and then to?
A
carry info from receptors to the CNS
4
Q
where do efferent neurons from and then to?
A
carry info from CNA to effectors/
5
Q
what are afferent neurons also called?
A
sensory neurons
6
Q
what are efferent neurons also called?
A
motor neurons.
7
Q
what is the purpose of interneurons?
A
link afferent to efferent within CNS
8
Q
what are the subdivisions of the CNS?
A
- cerebrum
- brainstem
- cerebellum
- spinal cord
9
Q
what are the 3 swellings that develop form the neural tube?
A
- forebrain (prosencephanlon)
- midbrain (mesencephalon)
- hindbrain (rhombencephalon)
10
Q
what does the telencephalon develop into?
A
cerebral hemisphere
11
Q
what does the diencephalon develop into?
A
thalamus and hypothalamus
12
Q
what does the mesencephalon develop into?
A
midbrain
13
Q
what does the metencephalon develop into?
A
pons and cerebellum
14
Q
what does the myelencehalon develop into?
A
medulla oblongata
15
Q
what do the 5 swelling of the brain development?
A
- telencephalon
- diencephalon
- mesencephalon
- metencephalon
- myelencehalon
16
Q
what is the fissure separating the 2 lobes called?
A
longitudinal fissure aka superior sagittal fissure
17
Q
what is the corpus cailosum?
A
white matter that joings the 2 brain hemispheres.
18
Q
what is the function of the corpus cailsum?
A
allow for communication between the 2 hemispheres of the brain.
19
Q
what are the 4 lobes of the brain?
A
- frontal
- parietal
- occipital
- temporal.
20
Q
what lobes are separated by the lateral sulcus?
A
separates the temporal lobe from the frontal and parietal.
21
Q
what lobes are separated by the central sulcus?
A
the frontal from the parietal.
22
Q
why is the surface of the cerebral hemisphere so heavily folded?
A
to increase surface aread - allowing more neurons.
23
Q
is the gyrus at the top or the bottom of the fold?
A
top.
24
Q
is the sulci at the top or the bottom of the fold?
A
bottom.
25
what vertebras are included in the cervical segment of the spinal cord?
C1- C8
26
what vertebras are included in the thoratic segment of the spinal cord?
T1-T12
27
what vertebras are included in the Lumbar segment of the spinal cord?
L1-L5
28
what vertebras are included in the Sacral segment of the spinal cord?
S1- S5
29
what are the 4 main segments of the spinal cord?
- cervical
- thoratic
- lumbar
- sacral
30
how many vertebrae are there in the spinal cord?
33
31
how many spinal nerves are in the spinal cord?
31
32
what type of information is in the dorsal white column?
sensory info
33
what type of information is in the lateral white column?
motor info
34
what type of information is in the ventral white column?
both motor and sensory information.
35
what is the purpose of the ventral white commisure?
it allows communication to both sides of the vertebrea
36
on what vertebrae's can the larteral horn be found?
T1-L2 and S2-S4
37
how does a message get send from the skin to the muscles via the PNS?
- skin
- down sensory fibre to dorsal root ganglion
- into dorsal root
- interneuron in the spine
- come out as a motor fibre to the skeletal muscles.
38
How does the reflex arc allow us to move more quickly away from danger?
it links sensory and motor in the spinal cord without the need to send the message to the brain.
39
what is the one cranial nerve that exits the dorsal surface of the brain?
Trochlea
40
what is the function of the hypothalamus?
regulates neuroendorine function (eg changing body temp/ hormones)
41
what is the function of the thalamus?
to get messages and send them on to the correct area of the brain.
42
what is the function of the epithalamus?
includes the pineal gland, to secrete melatonin, regulating sleep and wake cycles.
43
is the parietal lobe a sensory or motor cortex?
sensory
44
what does the parietal lobe control?
- language + comprehension
| - spatial orientation and awareness.
45
is the frontal lobe a sensory or motor cortex?
motor.
46
what does the frontal lobe control?
the regulation of emotions.
47
what does the temporal lobe control?
the regulation of emotions. as well as hearing.
48
in which area of the brain is general sensory information sent?
postcentral gyrus
49
in which area of the brain is visual information sent?
around calcarine sulcus and posterior aspect of occipital lobe.
50
in which area of the brain is auditory information sent?
heschl's gyrus.
51
in which area of the brain is motor information sent?
precentral gyrus.
52
why are secondary sensory and motor areas important?
they are involved in interpretation and understanding of the message. Organise the movement.
53
what area of the secondary auditory area in the brain contains motor fibres that are involved in the production of words?
Broca's area,
54
what area of the secondary auditory area in the brain contains sensory fibres that are involved in the understanding of language?
Wernicks area.
55
what is the effect of Broca's aphasia?
problems finding words and forming sentences.
56
what is the effect of wernickes aphasia?
problem understanding words and don't understand their own words.
57
why does the brain need a rich blood supply?
due to high metabolic demands.
58
what are the 2 arteries that supple the brain that are connected by the circle of willis?
vertebral artery
| carotid artery
59
how does the vertebral artery enter the skull?
via the foramen magnum
60
how does the carotid artery enter the skull?
via the carotid canal.
61
what is the vertebral artery a branch of?
the subclavian arteries.
62
what does the vertebral artery turn into when it fuses at the bottom of the brain stem?
basilar artery
63
what are the names of the 3 cerebella arteries?
- superior cerebella artery
- anterior inferior cerebella artery
- posterior inferior cerebella artery
64
over what structures of the brain can the 3 cerebella arteries be found?
over the pons and cerebella area.
65
what are the 3 cerebral arteries?
- posterior cerebral
- middle cerebral
- anterior cerebral
66
what areas of the brain does the posterior cerebral artery supply?
- occipital lobe
| - inferior and medial surfaces of temporal lobe.
67
what areas of the brain does the middle cerebral artery supply?
- lateral areas of frontal, temporal and parietal lobes.
68
what areas of the brain does the anterior cerebral artery supply?
- superior and medial areas of frontal and parietal lobes.
| - corpus callosum.
69
what does the circle of willis surround?
the optic chiasm and hypothalamus
70
what is the purpose of the circle of willis?
to ensure compensation of decreased blood flow if one vessel is blocked.
71
where does all the venous blood from the brain drain into?
internal jugular veins,
72
what are the 3 different types of meninges that cover the CNS?
- Dura mater
- arachnoid mater
- pia mater
73
which meninge follows the gyri and sulci?
pia mater
74
what are the layers of the dura mater attached to?
to bone and the arachnoid layer
75
as there are 2 layers of dura mater what does this result in?
where the 2 hemispheres meet there is a sagital sinus
76
what is a epidural haemorrhage?
torn maningeal artery
77
what is a subdural haemorrhage?
torn bridging veins
78
what is a subarachnoid haemorrhage?
torn cerebral artery
79
what is the dural infolding between the central hemispheres called?
flax cerebri
80
what is the dural infolding between the occipital lobes and the cerebellum called?
tentorium cerebelli
81
what is found located within the dural infoldings?
various venous (dural) sinuses.
82
what is the sinus at the top of the skull called?
superior sagittal sinus
83
what is the sinus between the 2 hemispheres running from the back to the front called?
inferior sagittal sinus.
84
what is the sinus at the back of the skull called?
confluence of sinuses.
85
why does the confluence of sinuses have this name?
because it joins the superior sagital and straight sinus.
86
what sinus connects the confluence of sinus and the inferior sagital sinus?
straight sinus
87
where is the epidural space found?
between bone and spinal cord
88
where is the subarachnoid space found?
around spinal cord inside the arachnoid mater
89
what is the purpose of the denticulate ligaments?
anchor the spinal cord in place.
90
what are the meninges of the spinal cord?
- Dura mater
- arachnoid mater
- pia mater
91
what produces CSF?
choroid plexus.
92
how does CSF escape the ventricular system into subarachnoid space?
via a series of apertures.
93
what allows the brain and spinal cord to 'float'?
to CSF that surrounds it.
94
what is CSF?
cerebrospinal fluid.
95
what is contained inside the CSF?
glucose, inorganic salts, little protein and few cells.
96
how much CSF is produced a day by the choroid plexus?
500ml/ day
97
why does the brain and spinal cord need to 'float'?
to reduce traction.
98
what are the purposes of CSF?
- Buoyancy
- Cushioning effect to dampen trauma
- transport of substances.
- provides a stable environment.
99
if CSF circulation is blocked what can it result in?
Hydrocephalus.
100
what is the somatoesthetic pathway?
general sensory pathway - carrying info from the skin etc to the brain.
101
what does the spinothalmic pathway modulate?
pain, temp, simple touch, some pressure.
102
what is gray matter?
collection of nerve cell bodies eg cortex and nucleus (CNS) and gangion (PNS)
103
what is white matter?
axons with gual sheath (myeline)
104
what type of cell bodies are in the peripheral ganglia?
pseudounipolar.
105
how do messages travel through the spinal cord to the brain?
- 1st neurone in cell body in dorsal root ganglion.
- fibre synapses in 2nd neuron in dorsal gret horn.
- axon of 2nd neuron crosses midline on the spinal cord in ventral white commissure.
- 2nd fibres asend in the spinothalamic tract to thalamus. (via the medulla)
- the fibres synapse 3rd neuron in the brain.
106
if you feel pain on the left side of your body what side of the brain will go to?
right side of the brain due to it crossing over in the spinal cord.
107
where does V1 exit the skull?
via the superior orbital fissure.
108
where does V2 exit the skull?
via the foramen rotundum.
109
where does V3 exit the skull?
via the formen ovale.
110
what is herpex zoster?
infection of the sensory roots of the trigeminal nerve.
111
what can herpex zoster cause?
shingles in infected area.
112
where are the cranial nerve nuclei located?
within the brainstem.
113
what are the 3 divisions of the trigeminal nucleus?
- mesencephalic nucleus
- pontine/ chief sensory nucleus
- spinal nucleus
114
where is the only motor trigeminal nuclei found?
on the pons.
115
what is the pathway for pain and temp vial the trigeminal nerve?
- 1st neuron cell body in Trigeminal ganglion
- these fibres run caudally in spinal tract of trigeminal
- synapses with 2nd Neuron in spinal nucleus
- cross the midline and asend in trigeminothalamic tract to the thalamus
116
what is the pathway from the body carrying pain and temp called?
spinothalamic pathway
117
what is the pathway from the teeth carrying pain and temp called?
trigeminothalamic pathway
118
how many neurons do pathways to the brain have?
3
119
what are the 2 layers of the retina of the eye called?
- non-neuronal layer
| - neural layer
120
what is the difference between the non-neuronal layer and the neural layer of the retina in the eye?
Non-neuronal layer = pigment, sites against the choroid and is light absorbing.
neural layer = photoreceptros, bipolar cells, ganglion cells.
121
what is the importance of knowing about the optic disk in the eye?
it is the blind spot of the eye as its where the optic nerve leaves the retina.
122
where is the highest visual acuity in the eye?
fovea
123
why does the fovea have the highest visual acuity in the eye
only has cones in this area.
124
where in the eye absorbs light first?
pigmented epithelium/
125
in the retina there are gangion cells and bipolar cells - what are these outgrowth of?
diencephalon.
126
within the visual pathway where are the first 2 neurons found?
in the retina.
127
what is papilloedema?
swelling of the optic disk due to a swelling of the optic nerve.
128
what causes papilloedema?
rise in CSF pressure,
129
what are the effects of papilloedema?
increased pressure compressing the central retinal vein, preventing venous drainage from the eye.
130
what are the symptoms of papilloedema?
- headaches.
- drowsiness
- blurred vision.
- vomiting
131
where do some of the fibres cross in the visual pathway?
at the optic chiasm.
132
which hemisphere does the left half of vision go to?
right hemisphere.
133
which hemisphere does the right half of vision go to?
left hemisphere.
134
which bank of the calcarine sulcus does the upper visual field go to?
lower bank.
135
which bank of the calcarine sulcus does the lower visual field go to?
upper bank.
136
why do some fibres cross at the optic chiasm?
so that from both eyes the left half of the visual field both go to the right hemisphere and that both eyes right side of the visual filed go to the left hemisphere,
137
the main focus of your field of vision goes to the anterior or posterior of the visual cortex?
posterior
138
outside of your main focus of your vision goes to the anterior or posterior of the visual cortex?
anterior.
139
what is scotoma?
localised path of blindness.
140
what is anopuia?
loss of one or more quadrants of the visual field.
141
what is hemianopia?
1/2 of the visual filed is lost.
142
what is quadranthopia?
1/4 of the visual field is lost.
143
what is homonymous?
visual field losses are similar for both sides.
144
what is heteronymous?
visual filed losses are on different sides.
145
what is monocular blindness?
blindness in one eye
146
what causes monocular blindness?
damage to the optic nerve of the now blind eye.
147
what is bitemporal hemianopia?
vision on either the inside of the eyes or outside of the eyes has gone.
148
what causes bitemporal hemianopia?
damage to the optic chiasma preventing nasal fibres from crossing.
149
what is homonymous hemianopia?
vision on either the right side or the left side of both eyes has gone.
150
what causes homonymous hemianopia?
damage to the optic tract.
151
in what bone is the ear found?
temporal bone
152
what is the purpose of the external ear?
receive sound waves
153
what is the purpose of the middle ear?
turn the sound waves into mechanical waves.
154
what is the purpose of the inner ear?
turn the mechanical waves in to electrical waves.
155
what structure separates the outer and middle ear?
the tympanic membrane
156
how does the middle ear communicate with the nasopharynx ?
via the eustachian tube.
157
what are the functions of the eustachian?
- provides ventilation
| - drains the middle ear.
158
what are the risks of the inner ear being connected to the nasopharynx?
- prone to infection.
159
what are the risks of the inner ear being connected to mastoid air cells?
infection may spread to middle cranial fossa.
160
what are the risks of the inner ear having the internal jugular veins lying inferior to it>
thrombosis risk.
161
what are the risks of the inner ear having hte internal carotid artery lying anterior to it>
link to pulsative tinnitus.
162
what are the 2 sense organs in the inner ear?
- vestibular system.
| - cochlea.
163
what fluid does the outer bony labyrinth of the inner ear contain?
perilympth
164
what fluid does the inner bony labyrinth of the inner ear contain?
endolympth
165
what is mean when saying the auditory pathway is polysymaptic?
many neurons so many synapses.
166
what is mean when saying the auditory pathway is tonotopically organised?
frequencies hit different areas in the brain.
167
what is mean when saying the auditory pathway is bilateral?
sound can be localised
168
what is the purpose of the cochlea duct?
separates the cochlea into 2 chambers.
169
what are the 2 chambers that the cochlea is seperated into by the cochlea duct?
- Scala Vestibuli (SV)
| - Scala Tympani (ST)
170
what is the area at the apex of the coclear that allows the Scala Vestibuli (SV) and Scala Tympani (ST) to communicate?
helicotrema.
171
as the fluid (perilympth) moves around the cochlea how does this effect the endolympth?
deforms it.
172
where are hair cells found?
in the organ of corti
173
what the the tips of the hair cells embedded into?
tectorial membrane.
174
what is the purpose of the the spiral organ of corti ?
to covert fluid pressure into electrical signals via the cochlear nerve.
175
what are the stages of the auditory pathway?
- cochlea
- spinal gangion
- cochlear nuclei
- Pons (superior olivary nucleus)
- Midbrain (inferior colliculus)
- Thalamus (medial geniculate nucleus)
- Cerebral cortex. (Heschls gyrus)
176
why can nerves travel form the cochlea nuclei to both sides of the brain?
to ensure that if one side is damage hearing will not be lost.
177
why can fibres from the auditory pathway cross at the midbrain?
to ensure that if one side is damage hearing will not be lost.
178
in the basilar membrane which area responds to low pitch?
apex
179
in the brain which area of the primary auditory cortex responds to low frequency sound?
anterolateral part.
180
in the brain which area of the primary auditory cortex responds to high frequency sound?
posterolateral part.
181
where is brocas and wernickes areas found?
in the secondary auditory area.
182
is Broca's area motor or sensory?
motor
183
is Wernicke's area motor or sensory?
sensory.
184
what artery supplies the secondary auditory area of the brain?
middle cerebral artery.
185
why is there a descending auditory pathway?
prevent ear damage due to nerves enabling us to tense due to a loud noise.
186
what are the physical symptoms associated with anxiety?
- racing heart
- heavy breathing
- sweating
- dry mouth
187
what is the function of the peripheral nervous system?
control external actions of the skin and muscles.
188
is the peripheral nervous system voluntary or involuntary?
voluntary
189
is the autonomic nervous system voluntary or involuntary?
involentry
190
what is the function of the autonomic nervous system?
control internal activity of organs and glands.
191
what are the 2 divisions of the autonomic nervous system?
- sympathetic (fight or flight)
| - Parasympathetic (rest and digest)
192
are autonomic visceral motor fibres efferent or afferent?
efferent
193
are autonomic visceral sensory fibres efferent or afferent?
afferent
194
where do autonomic visceral motor fibres go to ?
to smooth muscles, cardiac muscles or glands.
195
where do autonomic visceral sensory fibres go to ?
from sensory receptors in an internal organ.
196
in what spinal vertebras are both autonomic motor and sensory fibres found?
T1-L2 and S2-S4
197
how many neurons in the autonomic efferent chain?
2.
198
what is the pathway from brain/spinal cord to target organ/tissue for autonomic efferent?
- cell body in brain stem/ spinal cord
- travel down preganglionic fibre
- to autonomic ganglion
- down the post ganglionic neurone
- to target organ/ tissue.
199
what is the anatomical different between sympathetic and parasympathetic pathways from the spinal cord to the tissue.organ?
Sympathetic = ganglion is located closer to the spinal cord. so there is a longer postganglionic neuron.
parasympathetic = ganglion is located closer to the effector organ. so the preganglionic neurons are longer. Craniosacral.
200
what is meant by the term thoracolumbar? and does this apply to sympathetic or parasympathetic.
nerves come out of the spinal cord in the thorax - lumbar area.
sympathetic.
201
what is meant by the term Craniosacral? and does this apply to sympathetic or parasympathetic.
nerves comes from the brain and the very bottom of the spinal cord.
parasympathetic.
202
what is the neurotransmitter used in parasympathetic nerves?
Acetylcholine.
203
why is the there a localised effect of parasympathetic neurons?
due to the 1:1 ration of per and post gangionic neurons.
204
what is the pre-neurotransmitter used in sympathetic nerves?
Acetylcholine
205
what is the post-neurotransmitter used in sympathetic nerves?
noradrenaline / norepinephrine.
206
why is there a wide spread effect of sympathetic neurons?
due to 1 pregangiolnic neurone to many postganglionic neurones.
207
what is the sympathetic trunk?
interconnected chain of autonomic ganglia.
| site of synapes between pre and post ganglionic neurons.
208
where is the sympathetic trunk located?
either side of the entire vertebral column.
209
where does sympathetic preganglionic fibres leave the cord?
T1-L2.
210
what are the 3 options sympathetic pregasnglionic neurons can have ?
1) symapse at entry level.
2) pass through the first ganglioa without synapsing and then synapse in prevertebral ganglion. (closer to the organ tissue)
3) ascend or descend in the trunk to synapse in the truck (allowing it to synapse closer to the effector organ)
211
what is responsible for referred pain?
autonomic afferent (sensory)
