Neuro Anatomy Flashcards
1
Q
Median/Sagittal Plane
A
Vertical plane passing through sagittal suture of skull
2
Q
Planes parallel to the Sagittal plane are called…
A
Parasagittal planes
3
Q
Rostral vs Caudal direction
A
Rostral - towards nose
Caudal - towards tail
4
Q
Brain is divided into 3 parts
A
Hindbrain (rhombencephalon)
Midbrain (mesencephalon)
Forebrain (prosencephalon)
5
Q
Cerebellum responsible for…
A
Motor control of equilibrium, posture, muscle tone, movement co-ordination
6
Q
Brainstem comprises…
A
Ascending and descending tracts, cranial nerve nuclei and reticular formation
7
Q
Gyri
A
Rolls of cerebral cortex
8
Q
Sulci
A
Grooves between gyri
9
Q
Central Sulcus
A
Large groove separating frontal from parietal lobes
10
Q
Lateral Sulcus
A
Large fissure separating temporal lobes from parietal and frontal lobes
11
Q
Insula
A
Forms floor of the lateral sulcus
Functions include disgust, self-awareness, emotion
12
Q
Opercula (lips)
A
Parts of temporal, parietal and frontal lobes that overlie the insula
13
Q
Ventral =
Dorsal =
A
Anterior
Posterior
14
Q
What is the Corpus callosum?
A
Large bundle of white matter connecting the 2 hemispheres
15
Q
Where do the olefactory tracts run?
A
Inferior surface of frontal lobes
16
Q
Grey vs white matter
A
Grey - Lots of cell bodies
White - Axons, myelin sheath, some Glial cells
17
Q
Hindbrain (rhombencephalon) comprises…
A
Pons and Medulla
18
Q
Association fibres
A
Stay in same hemisphere they start in
19
Q
Commissural fibres
A
Connect between L and R hemispheres
20
Q
Projection fibres
A
Carry info from spinal cord up into cortex and back down from cortex into spinal cord
21
Q
Role of frontal lobes
A
Motor function, memory, language, judgement
22
Q
Motor cortex
A
Region of cerebral cortex responsible for signalling for movement
Size of cortex responsible for a part of the body is relative to the complexity of movement at that part (e.g- area dedicated to thumb similar to area dedicated to trunk even though trunk is much bigger)
23
Q
Role of temporal lobes
A
Language, memory, meaning of things, facial recognition
24
Q
Role of parietal lobes
A
Somatosensory
Dominant (usually left): perception, language, maths
Non dominant (usually right): visuospatial function
25
Role of occipital lobes
Visual
26
CSF in the skull sits between...
Pia mater and Arachnoid mater
27
Asymmetry of brain
R frontal and L occipital lobes protrude outwards more than their counterpart
28
Occipital poles
Posterior-most parts of occipital lobes
29
Optic nerves location
Pass backwards and medially converging in midline to form optic chiasma
Then pass backwards and laterally as the optic tracts
30
Mammillary bodies
2 rounded eminences behind the optic chiasma
31
Hypothalamus location
Behind optic chiasma up to and including the mammillary bodies (only part of diencephalon visible on outside of brain)
32
Cerebral peduncles
2 stalks attaching cerebrum to brainstem
33
Crus cerebri (plural = crura cerebri) of the cerebral peduncles
2 large masses of white matter emerging behind the mammillary bodies on each side
They pass backwards converging with midline of pons
34
Interpenduncular Fossa
Space between crura roofed over by arachnoid
35
Pons position in relation to crura
Situated immediately behind where crura meet in midline
36
What joins the 2 hemispheres of the cerebellum?
Central Vermis
37
Prefrontal cortex vs posterior portion of frontal lobe
Prefrontal cortex - Higher cognitive functions, determinants of personality
Posterior portion - motor and premotor areas
38
Broca's Area
In left inferior frontal gyrus
Important in language production and comprehension
39
Wernicke's Area
In superior temporal gyrus of L hemisphere
Concerned with understanding spoken word
40
Limbic lobe contains...
Hippocampus, fornix, amygdala
41
3 meningeal layers
Dura mater
Arachnoid mater
Pia mater
42
Dura mater layers
Outer endosteal layer - lines interior skull, adhering to, and sending blood vessels into cranial bones
Inner meningeal layer - envelopes CNS and continues as tube of dura around spinal cord and provides tubular sheaths for cranial nerves
43
Dural venous sinuses
Communicating blood filled spaces where the 2 dura layers have separated and folded over
44
Tentorium Cerebelli
Dura forming a thick fibrous roof over the posterior cranial fossa and the cerebellum
45
Straight sinus
Within tentorium cerebelli at its attachment to the falx cerebri
46
Transverse sinuses
Run along line of attachment of tentorium cerebelli to occipital bone
47
Cavernous sinus location
Lies lateral to body of the sphenoid
48
Trigeminal cave
Lies next to apex of petrous part of temporal bone and envelopes roots of the trigeminal nerve
49
Diaphragma sellae
Fold of dura mater which forms roof of pituitary fossa
50
Falx cerebelli
Small, vertical sickle-shaped reflection of dura separating the 2 lobes of the cerebellum
51
Foramen of Magendie role
Midline communication between IVth ventricle and subarachnoid space
52
Foramen of Lushka role
Lateral communication between IVth ventricle and subarachnoid space
53
Subarachnoid cisterns
Spaces between arachnoid and pia mater (pools of CSF)
54
Blood brain barrier
On brain surface, arteries lie in subarachnoid space. As vessels pass into brain, they're surrounded by prolongations of pia mater and some subarachnoid space which thins towards the capillaries (at this point pia and BM of endothelial cells fuse)
55
Arterial blood to the brain arrives within the skull via 2 pairs of vessels...
-Internal Carotid Arteries
-Vertebral Arteries
56
Internal Carotid Arteries supply...
-Anterior and Middle Cerebrum
-Diencephalon
57
Vertebral Arteries supply...
-Posterior Cerebrum
-Contents of Posterior Cranial Fossa
58
Path of Internal Carotid Artery
Arises at bifurcation of common carotid at level of upper border of thyroid cartilage
Ascends to base of skull where it enters through foramen lacerum to lie in carotid canal
Pierces dura forming cavernous sinus to enter cranial cavity
Divides into anterior and middle cerebral arteries at medial end of lateral sulcus
59
Anterior Cerebral Artery supplies...
Corpus callosum and medial aspects of the hemispheres
60
Middle Cerebral Artery supplies...
Majority of lateral surface of hemisphere and deep structures of anterior part of cerebral hemispheres
61
What connects the 2 anterior cerebral arteries?
Anterior Communicating Artery
62
What connects the internal carotid and posterior cerebral artery?
Posterior Communicating Artery
63
Where do the vertebral arteries enter the skull?
They then converge where?
To form what?
FORAMEN MAGNUM
Unite at midline at lower border of pons to form BASILAR ARTERY
64
Where does the Basilar Artery lie?
Anterior Median Fissure
65
Internal vs External Cerebral Veins
Internal - Run within the substance of brain tissue and end when they reach brain surface where they become external cerebral veins
External - Run on brain surface crossing subarachnoid space to drain into dural venous sinuses
66
Sinuses in the brain connect ____ to ____
Major cerebral veins to internal jugular veins
67
Where are the inferior and superior sagittal sinuses found?
The inferior and superior edges of the falx cerebri
68
Where is the straight sinus found?
Midline of tentorium cerebelli
69
Where is the transverse sinus found?
Posterior fixed margin of tentorium cerebelli
70
Where is the sigmoid sinus found?
Deep groove in mastoid part of temporal bone
71
Where is cavernous sinus found?
Beside body of sphenoid bone
72
Where is superior petrosal sinus found?
In attached lateral margin of tentorium cerebelli
73
Where is inferior petrosal sinus found?
Groove between petrous temporal bone and basal part of occipital bone
74
Emissary veins
Connect veins outside skull and intracranial venous sinuses to inside the cranial cavity (route for infection to spread into cranial cavity)
75
Largest aggregation of choroid plexus found...
In the choroid plexus
76
Through what does CSF pass through to go from lateral ventricles to IIIrd ventricle
Interventricular Foramen (of Munroe)
77
What does CSF pass through to go from IIIrd to IVth ventricle?
Cerebral aqueduct
78
IVth ventricle communicates with subarachnoid space via...
(CSF can then occupy subarachnoid space around brain and spinal cord)
-Median Foramen of Magendie
-Lateral Foramen of Luschka
79
Choroid plexus
Invaginations of vessels in ventricles producing a vascular fold of pia mater covered by an epithelium derived form ependymal lining of ventricle
80
CSF-Brain Barrier
Tight junctions between extracellular space of choroid plexus and inside ventricle except via the choroidal cells (enables control over CSF volume)
Resorption of CSF into venous drainage of brain occurs via tufts of arachnoid mater (arachnoid villi)
Villi calcify with age forming arachnoid granulations
81
Path of superior oblique
Originates in posterior of orbit, runs forward to pass through trochlear and inserts on posterior part of eyeball (in medial aspect of orbit)
82
Path of medial rectus
Runs along length of medial orbit deep to SO muscle
83
Muscles oculomotor (CN III) supplies
Medial Rectus
Superior Rectus
Inferior Rectus
Inferior Oblique
84
Muscles abducens nerve (CN VI) supplies
Lateral rectus
85
Lacrimal punti
Small medial holes in upper and lower eyelids
86
Nasolacrimal duct
Drains from inferior part of lacrimal sac to nasal cavity
87
Parasympathetic outflow from CNS via...
Oculomotor (CN III), facial (CN II), glossopharyngeal (CN IX), and vagus (CN X)
and S2-4
CN III and VII have branches to the orbit
88
Where do parasympathetic fibres in oculomotor nerve (CN III) originate?
Edinger-Westphal nucleus in mid brain and travel into the branch to the IO muscle but leave nerve to IO and enter the ciliary ganglion (fibres innervate ciliary muscle and sphincter pupillae)
89
Path of parasympathetic fibres in facial nerve (CN VII)
Leave facial nerve nerve in middle ear to synapse in a ganglion in the pterygopalatine fossa and supply lacrimal gland
90
Sympathetic outflow from CNS to orbit via...
T1-L2 (fibres pass into sympathetic trunks)
Fibres arise from T1 and pass up sympathetic trunk through the stellate ganglion to base of skull
Fibres leave superior cervical ganglion of sympathetic trunk to supply dilator pupillae muscle and blood vessels
91
Which muscles are supplied by the trochlear nerve (CN IV)?
Superior Oblique
92
SO muscle moves the eye...
Downward and outward
93
IO muscle moves the eye...
Upward and outward
94
What is the greater petrosal nerve a branch of?
Parasympathetic branch of facial nerve (CN VII)
Emerges from petrous temporal bone
95
Bone attachments to tympanic membrane
Malleus attaches to it and it articulates with incus
96
What is chorda tympani nerve a branch of?
Facial nerve (CN VII) and crosses tympanic membrane
97
Internal acoustic meatus
Lies in temporal bone existing between inner ear and posterior cranial fossa
Includes vestibulocochlear nerve (CN VIII) and facial nerve (CN VII)
98
Bulbopontine Sulcus (in pons)
Transverse groove at caudal border of pons
99
Basilar Sulcus (in pons)
Shallow sulcus in which the basilar artery runs
100
Middle cerebellar penduncles
Lateral extensions of neural tissue from pons to cerebellum
101
Anterior medulla fissure
Partial division of medulla in midline
102
Pyramid of medulla
Elongated eminence (swelling) marking position of corticospinal (pyramidal) tracts
103
Decussation of the pyramids (medulla)
Diagonally orientated fibre bundles crossing fissure via which 80% of corticospinal fibres cross midline entering opposite lateral white column of spinal cord
104
Olive
Eminence in medulla caused by underlying inferior olivary nucleus and is concerned with control of movement
105
Inferior Cerebellar peduncles
Forms posterolateral margin of medulla
Thick bundle of white matter passing into cerebellum
106
Superior Cerebellar peduncles
Attach midbrain to cerebellum
107
Tectum
Part of midbrain dorsal to aqueduct
Made up of colliculi
108
Tegmentum
Part of midbrain ventral to aqueduct
Made up of nerve fibres entering and leaving cerebral hemispheres
109
Superior Colliculi
Part of visual system (concerned with visual reflexes)
110
Inferior Colliculi
Part of auditory system (concerned with reflex looking towards a loud noise)
111
Pineal Gland
Endocrine gland that synthesises melatonin which modulates sleep patterns in both circadian and seasonal cycles
112
2 nerve pathways in midbrain lying just deep to surface
Inferior Brachium
Superior Brachium
113
Inferior Brachium
Conveys auditory info from medial geniculate body (nucleus) to inferior colliculi
114
Superior Brachium
Conveys visual info from lateral geniculate body (nucleus) to superior colliculi
115
What marks midline of posterior medulla?
Posterior Median Sulcus
116
The Gracile tubercle of the medulla is...
And it overlies the...
Round swelling either side of midline overlying the GRACILE FASCICULUS
117
Role of Gracile Fasciculus
Carries fine touch, vibration, proprioception from lower limb
118
The Cuneate tubercle of the medulla is...
And it overlies the...
A swelling lateral to the gracile tubercles overlying the CUNEATE FASCICULUS
119
Cuneate Fasciculus role
Fine touch, vibration, proprioception from upper limb
120
Tegmentum contains nuclei of...
Glossopharyngeal (CN IX)
Vagus (CN X)
Accessory (CN XI)
Hypoglossal (CN XII)
121
Cranial Nerve Sensory, Motor, or Both mnemonic
I) Some
II) Say
III) Marry
IV) Money
V) But
VI) My
VII) Brother
VIII) Says
IX) Big
X) Brains
XI) Matter
XII) More
122
What makes up PNS?
12 pairs of cranial nerves
31 pairs of spinal nerves
123
Cranial nerves I, II, III
I) Olfactory
II) Optic
III) Oculomotor
124
Cranial nerves IV, V, VI
IV) Trochlear
V) Trigeminal
VI) Abducens
125
Cranial nerves VII, VIII, IX
VII) Facial
VIII) Vestibulcochlear
IX) Glossopharyngeal
126
Cranial nerves X, XI, XII
X) Vagus
XI) Accessory
XII) Hypoglossal
127
Cranial nerves carrying parasympathetic fibres
III) Oculomotor
VII) Facial
IX) Glossopharyngeal
X) Vagus
128
Make up of cranial nerves with both sensory and motor fibres?
Input from sensory fibres travels to a different nucleus than input from motor fibres
129
CN V?
Trigeminal
V1) Opthalmic (superior orbital fissure, innervates general sensation to upper face)
V2) Maxillary (Foramen Rotundum, innervates midface)
V3) Mandibular (Foramen Ovale, innervates lower face and motor fibres to muscles in mastication)
130
Bulbopontine sulcus
Groove between pons and medulla
131
Fibre types of CN VII (Facial)
Sensory - taste anterior 2/3 tongue
Motor - muscles of facial expression
Parasympathetic - lacrimal gland, submandibular and sublingual salivary glands
132
The terminal part of the facial nerve divides into 5 branches where?
In the parotid - 5 branches spread out across face providing motor function
133
The 2 roots of facial nerve
Medial root - motor fibres
Lateral root - sensory and parasympathetic fibres
134
Which cranial nerves are tested in the gag reflex?
Light touch on back of pharynx
Afferent fibres = CN IX
Efferent fibres = CN X
Look for reflex contraction of palate
135
Other tests of vagus nerve
Listening to patient's voice:
Hoarseness = vocal cord paralysis
Nasal sound = soft palate paralysis
Ask patient to say "ah" looking for elevation of palate
Unilateral X lesion = palate and uvula deviate away form side of lesion (towards normal side)
136
Testing CN XI
Test SCM - patient turns their head against resistance
Test trapezius - look for symmetry when shrugging shoulders
137
Testing CN XII
Stick tongue out and should go straight forward
XIIth nerve lesion = ipsilateral muscles are paralysed
So contralateral muscles contract pushing tongue to side of lesion
138
Olfactory nerve
Attached to brain, not brainstem
Function: smell
Receptors: nasal cavity
Axons travel through cribriform plate -> olfactory bulb -> tracts -> temporal lobe
139
Optic nerve
Attached to brain not brainstem
Function: vision
Fibres travel from retina to primary visual cortex
140
Role and path of CN III, IV, VI
All motor (extraocular muscles)
Pash through superior orbital fissure
141
What does oculomotor innervate? What fibres does it carry?
Where are it's nuclei?
Where do nerves exit brainstem?
MR, SR, IR, IO, LPS
Carries parasympathetic fibres into the orbit to constrict pupil
Midbrain
Nerves exit between pons and medulla
142
What does trochlear innervate?
Where are it's nuclei?
SO
Midbrain
143
What does abducens innervate?
Where are its nuclei?
LR
Pons
144
What joins the 2 cerebral hemispheres?
Median Vermis
145
Ridges of cerebral cortex are called...
Folia which are delineated by closely set curving, transverse fissures
146
3 layers of cerebral cortex
Outer layer - grey matter
Cortex
Inner layer - white matter core (surrounds the Deep Nuclei)
147
Path of cerebral aqueduct
Runs through midbrain connecting IIIrd and IVth ventricles
148
Red nucleus
Circular mass of grey matter ventro-lateral to cerebral aqueduct
149
Substantia Nigra
Black band of nerve cells overlying crus cerebri ventro-lateral to red nucleus both sides
150
What marks the division between anterior and posterior lobes of each cerebellar hemisphere?
Primary Fissure
151
Horizontal Fissure of each cerebellar hemisphere marks...
Lateral and posterior margins of hemisphere
152
What is the anterior lobe of each cerebellar hemisphere bordered by posteriorly?
Primary Fissure
153
What is the anterior lobe of each cerebella hemisphere bordered by anteriorly?
Primary Fissure
154
What are the tonsils of the cerebellum?
A prominent rounded swelling of cerebellar cortex either side of vermis
Seen from inferior surface
155
Flocculus of cerebellum
Approximately ovoid shape lying immediately posterior to lateral foramen of IVth ventricle on each side partly covered by choroid plexus
Lies immediately caudal to entry point of CN VIII
156
Nodule of cerebellum
Continuous with flocculus via peduncle of white matter
157
Flocculo-nodular lobe of cerebellum
Flocculus and nodule together, primarily concerned with vestibular info
158
Tract found in middle cerebellar peduncles
Corticopontocerebellar - info from primary motor cortex of motor plan - same info goes to spine
159
Tract found in inferior cerebellar peduncles
Vestibulocerebellar tract - vestibular impulses from labyrinths, directly and via the vestibular nucleus
160
Spinocerebellar tracts
Sensory input for balance and position sense
Ventral spinocerebellar - superior cerebellar peduncles
Dorsal spinocerebellar - inferior cerebellar peduncles
161
Dentate nucleus
Largest, most lateral of the deep cerebellar nuclei
Zig-zag edged oval mass
Its major fibre bundles passing into superior cerebellar peduncle
162
Rhomboid fossa
Diamond shaped floor of IVth ventricle limited laterally by the cerebellar peduncles and posteriorly by cuneate and gracile tubercles
163
Gracile Tubercles
Medial dorsal columns carrying touch, vibration, two-point discrimination and proprioception from the lower limb
164
Cuneate Tubercles
Lateral dorsal columns carrying touch, vibration, two-point discrimination and proprioception from upper limb
165
Facial Colliculus
Rounded swelling caused by fibres of facial nerve in substance of pons curving around the nucleus of abducens nerve
166
Locus Coeruleus
Bluish-grey pigmented noradrenergic cells under ependyma at rostral half of the sulcus limitans
167
What are the Hypoglossal, Vagal and Vestibular Trigones?
Triangular areas overlying the nucleus of the CN in its name
168
Obex
Inferior apex of rhomboid fossa
169
Area Postrema
Small tongue-shaped area immediately rostro-lateral to obex
Associated with nausea control - chemoreceptive trigger zone for emetic response
170
Septum Pellucidum
Thin, triangular, vertical, double membrane separating anterior horns of L and R lateral ventricles running as a sheet from corpus callosum down to fornix
171
What separates the 2 halves of diencephalon?
IIIrd Ventricle
172
Interventricular Foramen
Permits CSF flow from lateral to IIIrd ventricle
173
Cerebral Aqueduct
Connection between IIIrd and IVth ventricle (travels through brainstem)
174
Paracentral Lobule
U-shaped gyrus containing respresentations of lower limb within the primary motor and somatic sensory areas of the cortex
175
Cingulate sulcus is situated...
Just above cingulate gyrus separating it from the rest of the hemisphere
176
What is the Striae of Genari?
White band in primary visual cortex running parallel with pial surface in mid-depth of grey matter
This feature gives the name Striate Cortex to the primary visual area
177
Primary Motor Cortex position
Anteriorly - aka pre-central gyrus (grey matter over twice as thick as that of the sensory)
178
Primary Somatosensory Cortex position
Posteriorly - aka post-central gyrus (thinner grey matter than motor)
179
Corpus Callosum connects...
2 halves of brain (broad arched band of white matter)
180
Fornix
Bundle of white matter beneath corpus callosum connecting hippocampus with diencephalon and precommissural septum
181
Commissure of the Fornix
Fibres from one hippocampus cross to opposite fornix and so back to opposite hippocampus
182
Fornix connects to mammillary bodies via...
Columns of the fornix
183
Anterior commissure
Thick white matter bundle interconnecting temporal lobes and olfactory structures of each side
184
Lamina Terminalis
Thin sheet of ependyma and pia extending downwards from rostrum of callosum and fornix to anterior wall of IIIrd ventricle
185
Interthalmic adhesion
Flattened grey disc joining the thalami of each side behind the interventricular foramen
186
Medial Geniculate Nucleus
Relays auditory info from midbrain to auditory cortex passing some fibres, via the inferior brachium, to the inferior colliculi
187
Lateral Geniculate Nucleus
Relays visual info from optic nerve to both visual cortex (via optic radiation for vision) and the superior colliculi (via the superior brachium for pupillary reflexes)
188
Ventral and Dorsal parts of diencephalon
Ventral - Hypothalamus
Dorsal - Thalamus
189
Association Fibres
Link cortical regions within 1 cerebral hemisphere
190
Commissural Fibres
Link similar functional areas of the 2 hemispheres
191
Projection fibres
Link cortex with subcortical regions (thalamus, spinal cord, etc)
192
2 basic functions of uniting the 2 cerebral hemispheres
1) Bringing together separate representations of the 2 halves of the body, the visual field and auditory surround
2) Uniting areas of cortex which have functions specialised to 1 hemisphere
193
Foramen Magendie
Links IVth ventricle and cisterna magna
194
Role of limbic system
Acts as an interface between internal and external environment
Role in learning
Role in regulation and translation of our emotional state into appropriate behaviour
195
Main parts of limbic system connected via...
The Papez Circuit
196
List the structures of the limbic system
Cingulate gyrus
Hippocampal formation
Parahippocampal gyrus
Anterior perforated substance
Septal nuclei
Uncus
Amygdala
197
Cingulate gyrus lies...
Just above corpus callosum
198
What lobe is the parahippocampal gyrus part of?
Temporal lobe
199
Uncus
Hook-shaped region of cortex
Anterior end of temporal lobe
Role in olfaction, emotions, memory
200
Choroid Fissure
C-shaped site of attachment of choroid plexus in the lateral ventricles (runs between fornix and thalamus)
201
Stria Terminalis
Slender bundle of white fibres accompanying curve of caudate around into temporal horn of ventricle
Connects amygdala to septum and hypothalamus
202
Fimbria
Efferent fibres from hippocampus heading to fornix forming flattened, longitudinal white matter bundle
203
Posterior Horn of Lateral Ventricle
Variable extension of lateral ventricle into occipital lobe
204
Pes Hippocampi
2-3 elevations in lower anterior surface of hippocampus (paw-like appearance)
205
Claustrum
Part of basal ganglia (as it's a subcortical nucleus derived from the telencephalon)
Receives from and projects to cerebral cortex
206
What separates claustrum from putamen?
Extreme capsule (white matter)
207
What separates putamen and lateral segment of globus pallidus?
Lateral medullary lamina (white matter)
208
What separates lateral and medial segments of globus pallidus?
Medial medullary lamina (white matter)
209
What type of matter is the globus pallidus?
Grey Matter
210
Forceps Major (contains fibres from callosum) connects...
Parietal to parietal and occipital to occipital lobes
211
Forceps Minor (contains fibres from callosum) connects...
Frontal lobes
212
Cisterna Magna
Subarachnoid space below the inferior surface of the cerebellum, behind the medulla
213
Vertebral column layout
Cervical - 7 vertebrae
Thoracic - 12 vertebrae
Lumbar - 5 vertebrae
Sacrum - 5 fused vertebrae
Coccyx - 4 or more fused rudimentary vertebrae
214
What is the uppermost palpable spinous process?
7th cervical vertebra (the vertebra prominent)
215
Highest point of iliac crest is in line with what part of the spine?
Interval between L3 and L4
216
Facets of spinous processes role
Guide and constrain motion of vertebrae
217
Change in spinal curvature from foetus -> after birth
Foetus - C shaped with concavity facing anteriorly
After birth - anterior convexity in cervical due to looking up, anterior convexity in lumbar due to weight bearing on legs
218
4 movements in vertebral column
Flexion
Extension
Lateral Flexion
Rotation
Rotation is maximum in thoracic but flexion and extension are limited in thoracic due to rib cage
219
Role of intervertebral discs
Withstand compression forces whilst being flexible enough to allow movement between vertebrae
220
Structure of intervertebral disc
Nucleus pulposus surrounded by an annulus fibrosis
221
Nucleus pulposus of intervertebral disc
Well hydrated gel containing proteoglycan, collagen and cartilage cells
222
Annulus fibrosis of intervertebral disc
10-12 concentric layers of collagen
Annulus fibrosis attaches to vertebral bodies as well as the posterior longitudinal ligament
223
Which muscle covers the vertebral column?
Erectus Spinae
224
What is the epidural space?
Space between vertebrae and dura mater of spinal cord
225
What is contained within the epidural space?
Small arteries supplying spinal cord and vertebral venus plexuses.
Veins in these plexuses (Batson's veins) contain no valves and communicate freely with intercostal and pelvic veins
226
31 spinal nerves come from...
8 cervical nerves (8th emerges below C7 vertebra)
12 thoracic nerves
5 lumbar nerves
5 sacral nerves
1 coccygeal nerve
227
What does dorsal root of spinal nerve carry?
Sensory fibres
228
What does ventral root of spinal nerve carry?
Motor fibres
229
Anterior and posterior roots of a spinal nerve join together at the...
Intervertebral foramen
230
After the intervertebral foramen spinal nerve divides immediately into...
Anterior and posterior rami containing both sensory and motor fibres
231
Spinal nerves leave the intervertebral canal through...
The intervertebral foramen
232
Boundaries of intervertebral foramen
Anteriorly bounded by bodies of adjoining vertebrae and the intervening intervertebral disc
Posteriorly bounded by synovial joints between the 2 superior and 2 inferior articular processes
233
Cells of origin of dorsal root fibres reside in...
the dorsal root ganglion
234
Conus medullaris
Tapering end of the spinal cord
235
Filum Terminale
Fibrous strand extending from conus medullaris to coccyx
236
Cauda Equina
Nerves from lower part of cord (sacral and lumbar) hanging obliquely downwards
237
Where would you do a lumbar puncture? Why?
L3/L4 as spinal cord finishes at L1/L2
Below that is Cauda Equina
238
What is a striatum?
Lentiform nucleus connected to caudate nucleus connected to amygdala
239
Amygdala role
Emotional response
240
Papez Circuit
Cingulate Gyrus
Parahippocampal Gyrus
Hippocampus
Fornix
Mammillary body
Thalamus
(back to cingulate gyrus)
241
Path of lateral corticospinal tract (descending)
Travels from motor area of cortex and decussates in medullary pyramids
242
Path of lateral spinothalamic tract (ascending)
Cross straight away at anterior nerve roots (before entering medulla)
243
Geniculate Fibres
Fibres in the region of the genu of the internal capsule; they originate in the motor part of the cerebral cortex
244
What process creates the pivot joint between C1 (atlas) and C2 (axis)?
Odontoid peg
245
Pupillary Light Reflex
Afferent limb (input) = CN II
Efferent limb (output) = parasympathetic fibres in CN III
Light shone into 1 eye: Ipsilateral pupil constricts = direct response
Contralateral pupil constricts = consensual response
246
Motor innervation to face
Part of motor cortex dedicated to upper face, part dedicated to lower face
Cell bodies of UMNs reside in the motor cortex and their axons travel to facial motor nuclei in pons
Axons of UMNs for both upper and lower face cross at the midline synapsing on the contralateral CN VII motor nucleus
Facial motor nucleus also receives input from region of ipsilateral motor cortex responsible for upper face
247
CN XII
Hypoglossal
Motor nerve - muscles of tongue
Arises from medulla
Leaves through hypoglossal canal
248
CN XI
Accessory
Cranial part - rootlets arise from medulla leaving via jugular foramen by joining the vagus
Spinal part - ventral horn spinal cord C1-5
Travels up through foramen magnum
Leaves again through jugular foramen
Innervates sternocleidomastoid and trapezius
249
CN IX
Glossopharyngeal
Sensory, motor, parasympathetic
Taste - posterior 1/3 of tongue
General sensation (touch, temp, pain) to pharynx, eustachian, posterior 1/3 tongue
Parasympathetic to parotid gland
Afferents from carotid sinus (baroreceptors) and carotid body (chemoreceptors)
250
CN X
Vagus
Sensory, motor, parasympathetic
General sensation - larynx, pharynx, oesophagus, EAM, tympanic membrane
Visceral afferents - thoracic and abdo viscera
Afferents from aortic bodies (chemoreceptors) and aortic arch (baroreceptors)
Motor - soft palate, pharynx, larynx
Parasymp - thoracic and abdo viscera
251
CN VIII
Vestibulocochlear
Sensory
Vestibular afferents -> vestibular nuclei (connect to spinal cord, cerebellum, nuclei of CN II,IV,VI, cerebral cortex for posture, balance, eye movements, conscious perception of head position)
Cochlear afferents -> cochlear nuclei (primary auditory cortex - conscious perception of sound, auditory association cortex - interpretation)
252
What is the auditory association area?
Wernicke's Area
253
What is the primary auditory cortex?
Superior temporal gyrus
254
Subarachnoid cisterns
Spaces where arachnoid membrane and pia mater aren't in close proximity and CSF forms pools/cisterns
