NEUROSCIENCE Flashcards
1
Q
what separates the temporal, frontal and parietal lobes
A
the lateral fissure
2
Q
where is the central sulcus found
A
it is from the longitudinal to the lateral fissure
3
Q
what does the central sulcus separate
A
the frontal from the parietal lobes
4
Q
what is the grove down the middle of the brain called
A
the longitudinal fissure
5
Q
what is found on the inferior surface of the brain
A
the frontal and temporal lobes, as well as the pons
6
Q
what are the three layers of the meninges
A
the dura mater, the arachnoid mater and the pia mater
7
Q
what are the two layers of the dura mater
A
the outer endosteal layer and the inner meningeal layer
8
Q
what is the arachnoid mater made from
A
loose web like substance - collagen fibres
9
Q
what is the function of the dura mater
A
it has a mechanical role, stops the brain moving in the skull and forms the venous sinuses
10
Q
what is the falx cerebri
A
strong crescent-shaped sheet that represents an invagination of the meningeal layer of the dura mater into the longitudinal fissure, found between the medial surfaces of the cerebral hemispheres
11
Q
what does the posterior circulation of the brain arise from
A
the vertebral arteries (and basilar)
12
Q
what is the functions of the frontal lobe
A
voluntary movement of the contralateral part of the brain. the dominant hemisphere has Broca’s area which controls speech. there is intellectual functioning and personality
13
Q
what is the function of the temporal lobe
A
understanding language and processing auditory information. Wernicke’s area is present here. Also involves in long term memory
14
Q
what is the function of the parietal lobe
A
receives and interprets sensation such as pain, touch, pressure, size, shape. important from proprioception
15
Q
what is the function of the occipital lobe
A
visual, and meaning of written words. Visuospatial processing and object/facial recognition and colour determination
16
Q
what are the arteries that are in the circle of willis
A
the internal carotid, middle, anterior and posterior cerebral arteries, joined by the anterior and posterior communicating arteries
17
Q
what are the branches off the basilar artery
A
the anterior inferior cerebellar artery , the pontine arteries and labyrinthine arteries, superior cerebellar artery
18
Q
what is a berry aneurysm
A
out pouching in the circle of willis which occurs at the bifurcations
19
Q
what part of the brain does the anterior cerebral artery supply
A
medial surface of each hemisphere, most of the frontal, most of the corpus callosum, some deep structures
20
Q
where does the middle cerebral artery supply
A
the lateral aspect of the brain - most of the primary motor and sensory cortex
21
Q
where does the posterior cerebral artery supply
A
occipital lobe, inferior and posterior temporal lobe, thalamus and choroid plexus
22
Q
what does loss of the anterior cerebral artery cause
A
loss of contralateral motor and sensory functions of the lower limbs. Loss of speech
23
Q
what does loss of the middle cerebral artery cause
A
contralateral motor and sensory function loss of the upper limb and face
24
Q
what does loss of the posterior cerebral artery cause
A
vision loss leading to contralateral homonymous hemianopia
25
what is the venous drainage of the brain
two veins - the internal and external cerebral veins, the internal veins drain into the external cerebral veins
26
where do the external cerebral veins drain into
into the dural venous
| sinuses
27
what are the main cerebral sinuses
the straight, inferior and superior sagittal sinuses, which all flow into the confluence of the sinuses.
28
where does blood flow after the confluence of the sinuses
into the transverse sinus, then to the sigmoid sinus, and finally into the internal jugular vein
29
where does the cavernous sinus flow into
the superior and inferior petrosal sinus
30
what is found in the cavernous sinus
Oculomotor, trochlear, ophthalmic, maxillary, abducens and trochlear nerves as well as the carotid artery
O TOM CAT
31
what cranial nerves have parasympathetic activity
10, 9, 7, 3
32
what is CN1
olfactory
33
what is the function of CN1
smell
34
what is the path that CN1 takes
olfactory epithelium to the olfactory bulb. from there to the primary olfaction cortex
35
what is the function of CN2
vision and pupillary reflex
36
what is the function of CN3
light reflex (constricts the pupil) and supplies all eye muscles bar the lateral rectus and the superior oblique
37
what is the function of CN4
supplies the superior oblique muscle of the eye
38
what is the function of CN5
supplies the face with the three divisions dividing the face up. the mandibular branch also has motor function which helps with mastication
39
what is the function of CN6
supplies the lateral rectus in the eye
40
what are the different divisions of the CN7
temporal, zygomatic, buccal, mandibular and cervical
| Ten Zombies Bit My Cat
41
what is the function of CN7
controls the muscles of facial expression, and gives taste sensation to anterior 2/3 of tongue
42
what is the function of CN8
supplies the vestibular system and cortical system in the ear for hearing and balance
43
what is the function of CN9
Sensory: Innervates the oropharynx, carotid body and sinus, posterior 1/3 of the tongue, middle ear cavity and Eustachian tube.
Special sensory: Provides taste sensation to the posterior 1/3 of the tongue.
Parasympathetic: Provides parasympathetic innervation to the parotid gland.
Motor: Innervates the stylopharyngeus muscle of the pharynx.
44
what is the function of CN10
Sensory: Innervates the skin of the external acoustic meatus and the internal surfaces of the laryngopharynx and larynx. Provides visceral sensation to the heart and abdominal viscera.
Special Sensory: Provides taste sensation to the epiglottis and root of the tongue.
Motor: Provides motor innervation to the majority of the muscles of the pharynx, soft palate and larynx.
Parasympathetic: Innervates the smooth muscle of the trachea, bronchi and gastro-intestinal tract and regulates heart rhythm.
45
What is the function of CN11
supplies motor function to the trapezius and sternocleidomastoid muscle
46
what is the function of CN12
it innervates the extrinsic and intrinsic muscles of the tongue
47
what are the three layers of the eye
the outer, middle and inner eye
48
what is in the outer eye
the sclera (white part) and the cornea which is the first point of refraction
49
what is in the middle eye
the iris which contains the sphincter pupillae, the dilator papillae and the colour of the eye, and the choroid, the ciliary body and the lens
50
what is in the inner eye
the retina which detects light , has an outer pigmented layer which has melanin and an inner neural layer which contains photoreceptors
51
what are the 6 main muscles of the eye
the superior, inferior, lateral and medial rectus
| the superior and inferior oblique
52
what is the function of the lateral rectus
moves the eye away from the midline - abduction
53
what is the function of the medial rectus
adducts the eye, brings the eye closer to the midline
54
what is the function of the superior rectus
brings the eye upward, also has a slight adduction and intorsion effect
55
what is the function of the inferior oblique
corrects adduction from the superior rectus (extorsion)
56
what is the function of the inferior rectus
looks down and abducts the eye extorsion
57
what is the function of the superior oblique
corrects abduction from the interior rectus - intorsion
58
what do you have to do to the visual field to give you the retinal field
you have to flip it horizontally and then vertically
| - same as flipping it diagonally
59
describe the optic pathway
the left and right optic nerves meet at the optic chiasm. here fibres from the medial retinal field (both eyes) decussates. the two optic tracts then travel to the right and left geniculate nucleus and then to the visual cortex, travelling through either the temporal or parietal lobe (upper and lower radiations)
60
what happens if you damage an optic tract
you get contralateral homonymous hemianopia (lose the same side of vision on both eyes)
61
what is the external ear
the auricle, the external acoustic meatus and the tympanic membrane
62
what is the middle ear
middle ear bones, muscles and cavity
63
what are the middle ear bones
the ossicles - the malleus, the incus and stapes.
| they connect middle and inner ear
64
what are the middle ear muscles
the stapedius and the tensor tympani
65
what is the function of the stapedius muscle
to dampen the stapes bone
66
what is the function of the tensor tympani
it tenses the tympanic membrane to prevent excessive vibrations
67
what is the middle ear cavity
the Eustachian tube which connects the inner ear to the nasopharynx
68
what is the purpose of the Eustachian tube
to balance pressure on either side of the tympanic membrane
69
what are the sections of the inner ear
the semicircular canals, the vestibule and the cochlea
70
what is the function of the semicircular canals
detects changes in dynamic equilibrium and is important in balance
71
what is the function of the vestibule of the inner ear
utricle and saccule - detects changes in dynamic equilibrium (position)
72
what is the function of the cochlea
sound detection
73
what are the parts of the cochlea
scala vestibuli, scala media/cochlear duct - organ of corti and scala tympani
74
what part of the tectorial membrane detects high pitched and low pitched sounds
the far end of the membrane detects low pitched sound, and the close end detects high pitched sound
75
what is the pathway that the CN8 takes
cochlear nucleus, superior olivary nucleus, lateral lemniscus, inferior colliculus, medial geniculate body, auditory cortex
76
what is the function of the basal ganglia
important in control of movement - smooth and fine tuning of movement
77
what are the parts of the basal ganglia
caudate nucleus, thalamus, external globus pallidus, internal global pallidus, substantia nigra, putamen
78
what structure does the caudate and putamen form
the striatum
79
what structure does the globus pallidus and putamen form
the lentiform nucleus
80
what is the substantia nigra made up of
the pars reticularis and pars compacta
81
what are the three pathways involved with the basal ganglia
the direct, indirect and nigrostriatal
82
what is the function of the direct basal ganglia pathway
stimulates desirable movement
83
what is the function of the indirect basal ganglia pathway
inhibits undesirable movement
84
what is the function of the nigrostriatal basal ganglia pathway
modulates the direct and indirect pathways
85
what happens in parkinsons
there is a depletion of dopamine in the substantia nigra
86
what happens in huntingtons
there is too many CAG repeats which causes too much dopamine (not enough GABA to inhibit it)
87
what are the two sections of the sphenoid bone
the petrous and squamous parts
88
where does CN 1 leave the skull
the cribriform plate of the ethmoid bone
89
where does CN2 leave the skull
the optic canal
90
where does the CN3 leave the skull
the superior orbital fissure
91
where does CN4 leave the skull
the superior orbital fissure
92
where does CN5 leave the skull
ophthalmic - superior orbital fissure
maxillary - foramen rotundum
mandibular - foramen ovalae
93
where does CN6 leave the skull
superior orbital fissure
94
where does CN7 leave the skull
internal acoustic meatus
95
where does CN8 leave the skull
the internal acoustic meatus
96
where does CN9 leave the skull
jugular foramen
97
where does CN10 leave the skull
the jugular foramen
98
where does CN11 leave the skull
the jugular foramen
99
where does CN12 leave the skull
the hypoglossal canal
100
what passes through the foramen spinosum
the middle meningeal artery (for the jaw and meninges)
101
what path does the internal carotid artery take
enters into the base of the skull and through the petrous portion of the temporal bone (carotid canal) and then travels superior to the foramen lacerum, doing a right angle to enter the skull
102
what are the sections of the spine
```
cervical - 7
thoracic - 12
lumbar - 5
sacrum - 5 fused
coccyx - 4 fused
```
103
what is the anterior portion of the vertebrae
the vertebral body
104
what are the transverse processes of the spine
small bony projection off the right and left side of each vertebrae
105
where are the spinal processes of the vertebrae
Spinous process is a bony projection off the posterior (back) of each vertebra
106
what are the defining features of the cervical vertebra
atlas, axis, there are bifid spinous processes and a transverse foramen
107
what are the defining features of the thoracic vertebra
they have rib articulations by the costovertebral joints. they have longer thin spinal processes
108
what are the defining features of the lumbar vertebra
the vertebral body is much lager, the spinous processes are thicker and there is triangular foramen
109
what are the features of the spinal cord
there are two thicker cervical and lumbar enlargements. spinal cord ends at the conus medullaris and becomes the cauda equina from L2 and finally ends with the filum terminale
110
where does an epidural go
goes between the dura and the vertebral bodies
111
where does spinal anesthetic go
between the dura and subarachnoid space
112
where does a lumbar puncture go
inserts into the subarachnoid space to take a sample of CSF
| L3/4
113
what nerves are in the dorsal/posterior root
sensory
114
what nerves are in the anterior/ventral root
motor
115
what are the two divisions of the spinothalamic tract
lateral and anterior
116
what does the anterior spinothalamic tract detect
crude touch and pressure
117
what does the lateral spinothalamic tract detect
temperature and pain
118
what does the DCML detect
fine touch, vibration and proprioception
119
what is the path the DCML takes
upper limb - T6 and above, with information traveling in the fasciculus cuneatus in the lateral portion. this synapses in the nucleus cuneatus. T6 and below travels in the fasciculus gracile in the medial portion and synapses at the gracile nucleus.
it decussates at the medulla to the thalamus and then to the sensory cortex
120
what are the spinocerebellar tracts
posterior spinocerebellar
cuneocerebellar
anterior cerebellar
rostral cerebellar
121
what does the posterior spinocerebellar tract detect
proprioceptive sensation in the lower limbs - ipsilateral
122
what does the cuneocerebellar tract detect
proprioceptive sensation from upper limbs - ipsilateral
123
what does the anterior spinocerebellar tract detect
sensation from lower limbs and ipsilateral but it decussates twice
124
what does the rostral spinocerebellar tract detect
sensation in upper limbs and ipsilateral
125
what is the path of the corticospinal tract
starts in the motor cortex, moving to the internal capsule, crus cerebri and then divides at the most inferior aspect of the medulla oblongata into anterior and lateral.
lateral (80%) decussates straight after the medulla and supplies muscle fibres in the body. the anterior remains ipsilateral and decussates at the exit level in the spine
126
what happens in a lenticulostriate artery hemorrhage/stroke
can cause damage to the internal capsule which means no motor/sensory function
127
what are the extrapyramidal tracts
vestibulospinal, reticulospinal, rubrospinal, tectospinal
128
what is the vestibulospinal tract for
balance and posture information to antigravity muscles - flexors and extensors
129
what is the reticulospinal tract function
medial from the pons involved in voluntary movement and increases muscle tone
130
what is the rubrospinal tract function
red nucleus in involved in fine hand movement - decussates
131
what is the tectospinal tract function
vision - controls movement of the head to visual stimuli. decussates
132
what are the two main neurotransmitters in the CNS
glutamic acid (excitatory) and GABA (inhibitory)
133
what are the two main neurotransmitters in the PNS
acetylcholine and noradrenaline
134
Woman has a stab wound to the back which has completely severed the right side of her spinal cord at T12. what typical pattern of a hemi-section of the spinal cord
There everything on the right will be affected below the level of damage
Below T6 there will be no corticospinal (motor) to ipsilateral lower limbs
Damage to the DCML ipsilateral loss of vibration, pine touch and proprioception
On the contralateral side there will be spinothalamic problems, you will lose pain, temperature and crude touch sensations
135
what is the motor supply to the tongue
all intrinsic muscles are supplied by the hypoglossal nerve 12 , except the palatoglossus which is supplied by nerve 10
136
what is the general sensation nerve supply to the tongue
anterior 2/3 is the inguinal branch of the mandibular nerve
posterior 1/3 is by the glossopharyngeal nerve
the base of the tongue is by the superior laryngeal nerve (vagus)
137
what is taste nerve supply of the tongue
anterior 2/3 by the chorda tympani branch of the facial
posterior 1/3 by the glossopharyngeal nerve
base of the tongue is by the superior laryngeal nerve (vagus)
138
what happens in upper motor neuron damage
hypertonia, Babinski sign, hyperreflexia, increased spasticity, decreased control of movement
139
what happens in lower motor neuron lesion
muscle paralysis, fasciculations, hypotonia, hyporeflexia, muscle weakness and wasting
140
what happens when there is an optic nerve lesion
monocular vision loss
141
what happens when there is a lesion at the optic chiasm
bitemporal hemianopia
| - half blindness in both eyes
142
what happens when there is a lesion in one of the optic tracts
homonymous hemianopia
| -loose vision on the same side of both eyes
143
what happens when you have a lesion in the optic radiations
quadrantanopia - will be either inferior or superior depending on if the inferior or superior optic radiations are damaged
144
what cranial nerve supplies the levator palpebrae superioris
the oculomotor nerve
145
what is macula sparing
macular sparing is visual field loss that preserves vision in the center of the visual field
146
what nerve supplies the frontal, ethmoid and sphenoid sinuses
the ophthalmic division of the trigeminal nerve
147
what nerve supplies the maxillary and sphenoid sinuses
the maxillary division of the trigeminal nerve
148
what is bells palsy
it is unilateral weakness to the fac due to an issue with the facial nerve
149
which of the cranial nerves leave the brainstem
from cranial nerve 3 onward
150
what are the different neuroglial cells
schwann cells, atrocytes, microglial cells, ependymal cells
151
what is the function of astrocytes
coats capillaries, provides physical support and can uptake certain neurotransmitters and potassium ions - helps maintain blood brain barrier
152
what is the function of microglial cells
protection from bacteria and viruses, helps with reaggregation after injury
153
what is the function of ependymal cells
small ciliated cuboidal epithelial cells that line the ventricles and make CSF
154
what is the diencephalon
The diencephalon is a small part of the brain that is mostly hidden from view when you are looking at the outside of the brain. It is divided into four parts: the epithalamus, thalamus, subthalamus, and hypothalamus.
155
what is the function of the hypothalamus
for emotions as well as controlling your hormone system
156
where is the cingulate gyrus found
it is found above the corpus callosum
157
what is the corpus callosum
the area which connects the two hemispheres of the brain
158
what is the function of the limbic system
short term memory, emotions and behaviour
159
what structures are found in the limbic system
the amygdala, hippocampus, thalamus, hypothalamus, basal ganglia, and cingulate gyrus.
160
what connects the cerebellum to the brainstem
the peduncles,
| superior, middle and inferior
161
what is the function of the superior peduncle
connects the cerebellum to the midbrain, feedback to the cerebrum
162
what is the function of the middle peduncle
conveys impulses of voluntary movement from the cerebrum through the pons to the cerebrum
163
what is the function of the inferior peduncle
connects the cerebellum to the medulla and the spinal cord, it contains both incoming vestibular and proprioceptive fibres and outgoing motor fibres
164
how does the cerebellum help with movement
Motor cortex will send signals via the thalamus to the cerebellum - intent to start movement. This will be sent through the middle peduncle.
Information from the proprioceptors will enter into cerebellum via the inferior peduncles. The cerebellum will send signals via the superior peduncle, via thalamus to the motor cortex. Then the motor cortex will send a signal from the motor cortex via the brainstem to the muscles.
165
which spinal tract is involved with pain sensation
the spinothalamic tract
166
what is the function of the basal ganglia
Subcortical structures in deep white matter - extrapyramidal motor movement
Regulation of involuntary movement
Fine tunes voluntary movement
Involved in posture
167
what nerves supply the external ear
trigeminal, C2 and C3 spinal nerves
168
what structures make up the uvula
the choroid ciliary bodies and the iris
169
what fluid is found in the posterior cavity of the eye
vitreous humour
170
what fluid is found in the posterior chamber of the anterior cavity of the eye
aqueous humour
171
what are the sinuses in the head
sphenoid sinus, frontal sinus, maxillary sinus, ethmoid sinus
172
what is the inferior border of the nasal cavity
the palate - hard and soft
173
where is the sphenoid sinus in relation to the nasal cavity
posterior and superior
174
what is present on either side of the nasal cavity
the nasal conchae - inferior, middle and superior
175
what is found behind the nasal conchae
the nasal meatus - inferior middle and superior
176
where does the sphenoid sinus drain into
the superior meatus
177
where does the frontal sinus drain into
the middle meatus
178
what is olfactory epithelium
pseudostratified columnar epithelium with goblet cells
179
where does the maxillary sinus drain into
the middle meatus
180
where does the ethmoid sinus train into
the middle and superior meatus
181
what is ptosis
inability to lift the eyelid properly
182
what is the roof of the orbit of the eye
the frontal and sphenoid bone
183
what is the medial boundary of the orbit of the eye
the maxilla, lacrimal, ethmoid and sphenoid bone
184
what is the inferior border of the orbit of the eye
the roof of the maxillary sinus (maxilla, zygomatic and palatine bones)
185
what is the lateral border of the orbit of the eye
zygomatic bone and wing of sphenoid bone
186
what is accommodation
as light passes through the eye, it is bent by the cornea and lens onto the retina.
this occurs when you focus on something up close
187
what are the two muscles of the iris
the sphincter and dilator muscles
188
what does parasympathetic innervation to iris muscles cause
sphincter muscle innervation, contraction of the iris causing a rounded strong lens, and smaller pupil
189
what is the outermost layer of the eye
the conjunctiva
190
what are the emissary veins of the skull
those that are coming from outside the skull
191
what are the diploic veins of the skull
they drain the bones of the skull
192
what is the falx cerebri
a fold in the dura mater which is between the cerebral hemispheres
193
what is the pathway of the ophthalmic vein to the internal jugular vein
ophthalmic vein, cavernous sinus, petrosal sinuses, internal jugular vein
194
what are the two main functions of the meninges
support network for the brain and vasculature and acts with the CSF to protect the brain from mechanical damage
195
where is CSF produced in the brain
the choroid plexus - by ependymal cells
196
what are the ventricles of the brain
the two lateral ventricles, 3rd and 4th ventricle
197
how does CSF drain between the third and fourth ventricle
via the cerebral aqueduct
198
how does CSF drain into the subarachnoid space
via the foramina of lushka, or via the foramen of megendie
199
where does the fourth ventricle become the central canal
at the obex
200
what are the structures of the forebrain
the telencephalon and the diencephalon
201
what is the structure of the midbrain
the mesencephalon
202
what is are the structures of the hindbrain
the metencephalon and myelencephalon
203
what is found in the telencephalon
the cerebral hemispheres
204
what is found in the diencephalon
the thalamus and hypothalamus
205
what is found in the metencephalon
the cerebellum and pons
206
what is found in the myelencephalon
the medulla
207
what is Broca's area responsible for
language production - control of mouth and laryngeal muscles
208
what is Wernickes area responsible for
understanding speech and written language
209
what does the direct pathway of the basal ganglia do
it initiates motor movement - excitatory
210
what does the indirect pathway of the basal ganglia do
it inhibits motor movement
211
describe the direct pathway of the basal ganglia
the motor cortex excites the striatum which in turn inhibits the internal globus pallidus and the substantia nigra pars reticulata. this feeds back to the thalamus which sends excitation to the motor cortex and initiates movement
212
describe the indirect pathway of the basal ganglia
Primary motor cortex sends excitatory signals to the putamen (dorsal striatum) via glutamate
This results in the striatum sending inhibitory signals to the external globus pallidus via GABA
This inhibits the external globus pallidus so it cannot inhibit the subthalamic nucleus
Therefore, the subthalamic nucleus sends excitatory signals to the internal globus pallidus and pars reticulata via glutamate
This results in inhibitory signals being sent to the thalamus via GABA causing a decrease or stop in movement
213
what structures does the limbic system include
the amygdala, the fornix, the hippocampus, the anterior thalamic nuclei, the hypothalamus
214
what is the papez circuit
the part of the limbic system responsible for memory processing
215
what is the path of the papez circuit
cingulate gyrus to parahippocampal region (via cingulum). then to the hippocampus. from the hippocampus to the mammillary bodies via the fornix. from the mammillary bodies to the anterior thalamic nuclei via the mammillothalamic tract, and then back to the cingulate gyrus
216
what is the function of the midbrain
motor control, vision, hearing, sleep, temperature regulation
217
what is the function of the pons
breathing control, connection between cerebrum and cerebellum, many spinal tracts pass through here
218
what is the function of the medulla
cardiac, respiratory, vomiting and vasomotor control. sleep wake cycle. many spinal tracts pass through here
219
what are the sections of the midbrain
ventral portion - tegmentum
dorsal portion - tectum
made up of the superior and inferior colliculi
220
what are the cerebral peduncles
they are white matter which connects the cerebral hemispheres with the brainstem (midbrain)
221
what is the periaqueductal grey matter
found in the midbrain, surrounding the cerebral aqueduct - it has a role in the autonomic functions of behaviour and pain
222
what cranial nerve nuclei are present in the pons
The nuclei of the trigeminal nerve (V), abducens nerve (VI), facial nerve (VII) and vestibulocochlear nerve (VIII) are located in the pons
223
what cranial nerve nuclei are in the medulla
The nuclei of the glossopharyngeal nerve (IX), vagus nerve (X), accessory nerve (XI) and hypoglossal nerve (XII) are located in the medulla. The fibers of these cranial nerves exit the brainstem from these nuclei
224
what cranial nerve nuclei are in the midbrain
The nuclei of the oculomotor nerve (III) and trochlear nerve (IV) are located in the midbrain.
225
what structures are found in the medulla
the pyramids, the olivary nucleus, the anterior fissure, the cochlear nuclei
226
what is the central joining structure of the cerebellum
the vermis
227
what structures does the corda equina innervate
pelvic organs, bladder, sphincters and lower limb muscles
228
where do the extrapyramidal tracts originate from
the brainstem
229
what does the intermediate column and lateral horn innervate
visceral and pelvic organs
230
what is the corticobulbar tract
it sends voluntary motor control to the muscles of the head and neck
231
what are some examples of spinal reflexes
biceps reflex - C5-6
Patellar reflex - L2-4
triceps reflex - C7-8
Achilles reflex - S1
232
what is the prosencephalon
the embryonic forebrain
233
what is the rhombencephalon
the embryonic hindbrain
234
describe an action potential
an action potential propagating down an axon causes voltage gated sodium channels to open, causing sodium to move into the cell. this causes membrane potential to rise above threshold (-55mV) causing depolarisation. At 30mV sodium channels close and potassium channels open, causing repolarisation as potassium moves out the cell (get hyperpolarisation with a refractory period)
235
what are the two types of summation
spatial - several presynaptic to 1 post
| temporal - increased frequency
236
what is a motor unit
an alpha neuron plus all extrafusal fibres it innervates
237
what is a muscle spindle
an afferent neuron wrapped round an intrafusal fibre
238
what is the efferent supply for a muscle spindle
gamma neurons = prevents the intrafusal fibre from becoming slack
239
what is the afferent supply for muscle spindles
type 1a and type 2 fibres (type 2 are slower)
240
what do muscle spindles detect
amount of stretch, and the rate of change of length of a muscle
241
what does a golgi tendon organ detect
amount of tension/weight of a muscle
242
what is a golgi tendon organ
afferent fibres wrapped round collagen bundles in a muscle tendon
243
What afferent fibres are golgi tendon organs associated with
Type 1 b fibres
244
What is the purpose of a golfi tendon organ
To prevent over load or over stretch of a muscle
245
what is the cerebral peduncle
it is the midbrain ventral to the aqueduct
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what are the gyri of the brain
the rolls of cerebral cortex
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what are the sulci of the brain
the grooves between the gyri
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what is the foramen of magendie
a midline communication between the 4th ventricle and the subarachnoid space
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what is the foramen of luschka
a lateral communication between the 4th ventricle and subarachnoid space
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where do the arteries of the brain lie
in the subarachnoid space
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what is the internal carotid system
internal carotid enters in via the temporal bone to lie in the carotid canal. the artery then pierces the dura forming the roof of the cavernous sinus to enter the cranial cavity. when it reaches the anterior perforated substance at the middle end of the lateral sulcus it divides into its terminal branches - anterior and middle cerebral arteries
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where does the vertebral artery arise from
the first part of the subclavian artery
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what are the internal cerebral veins
these run within the substance of brain tissue and end when they reach the surface of the brain where they become the external cerebral veins
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what are the external cerebral veins
these run onto the surface of the brain crossing the subarachnoid space to drain into the dural venous sinuses
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where does the frontal part of the brain sit in the skull
in the anterior cranial fossa
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what is contained within the middle cranial fossa
temporal, parietal and occipital lobed of the brain
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what is contained within the posterior cranial fossa
the occipital bone, the foramen magnum, the hypoglossal canal and the internal acoustic meatus
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what would the symptoms of a raised intercranial pressure be
headache, nausea, visual disturbance, later altered consciousness
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what does the lacrimal nerve supply
the lacrimal gland - tear duct
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what are the lacrimal puncti
the are small holes in the upper and lower eyelids
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what is the parasympathetic outflow from the CNS via
the III, VII, IX and X cranial nerves as well as the sacral spinal segments 2, 3 and 4
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where do the parasympathetic fibres in the third cranial nerve originate from
from the edinger - westphal nucleus in the mid brain
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what do the parasympathetic fibres in the VII cranial nerve supply
the lacrimal gland
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what is the sympathetic outflow from the CNS via
the spinal segments Thoracic 1 - Lumbar 2
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what is jugular foramen syndrome
compression of multiple lower cranial nerves (IX, X, XI) leads to signs and symptoms including dysphonia, loss of gag reflex, and unilateral wasting of sternocleidomastoid and trapezius
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what part o the brainstem are the mamillary bodies found on
the midbrain
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where is the interpeduncular fossa found
on the midbrain
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what is the basilar sulcus and where is it found
it is a shallow sulcus where the basilar artery runs and it is in the pons
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what is the anterior median fissure and where is it found
a partial division - found in the medulla (ventral)
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what are the pyramids and where are they found
they are elongated swellings making the position of the underlying fibres passeing from the cerebral hemisphere to the spine - corticospinal tract
it is found on the medulla
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what are the olives and where are they found
this is lateral to the ventrolateral sulcus and is caused by the presence of the underlying inferior olivary nucleus (movement)
- found in the midbrain
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what partof the midbrain makes up the tectum
the midbrain dorsal to the aqueduct
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what part of the midbrain makes up the tegmentum
the midbrain ventral to the aqueduct - made up of nerve fibres entering and leaving the cerebral hemispheres
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what is the superior colliculi and where is it found
it is part of the visual system - concerned with eye reflex and is found in the midbrain
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what is the inferior colliculi and where is it found
it is part of the auditory system and is concerned with the reflex of looking towards a noise
- found in the midbrain
276
what is the pineal glands function and where is it found
it is found in the midbrain, and secretes melatonin
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what is the inferior brachiom pathway
conveys auditory information from the medial geniculate body to the inferior colliculi
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what is the function of the superior brachium
conveys visual information from the lateral geniculate body to the superior colliculi
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what is the contents of the tegmentum
the nuclei of the abducent, facial, trigeminal, glossopharyngeal, vagus, accessory and hypoglossal nerves
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what is the gracile tubercle found on the medulla
a round swelling on either side of the midline
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what is the cuneate tubercle of the medulla
a swelling lateral to the gracile tubercle
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what are the sensory cranial nerves (not both)
I, II, VIII
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what are the motor cranial nerves (not both)
III, IV, VI, XI, XII
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what are the cranial nerves that supply both sensory and motor function
V, VII, IX, X
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what part of the brain does the 12 cranial nerves have their nuclei
1 and 2 - in the cerebrum
3 and 4 - from the midbrain
5, 6, 7, and 8 - from the pons
9, 10, 11 and 12 from the medulla
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what is the only cranial nerve that comes from the back (posterior) of the brainstem
the trochlear nerve
287
what are the ridges of the cerebellum called
folia
288
what is the function of the cerebral aqueduct
it interconnects the thirst and the fourth ventricle
289
what does the primary fissure of the cerebellum separate
the anterior and posterior lobes
290
what is the tonsil of the cerebellum
it is a prominent rounded swelling of the cerebellar cortex anterior on either side of the vermis
291
what is the flocculo-nodular love associated with
it is the floccus and the noducle together and is primarily concerned with vestibular information
292
what is the dentate nucleus of the cerebellum
it is the largest and most lateral of the deep cerebellar nuclei, and passes to the superior cerebellar peduncle. it is afferent, and uses sensory information about balance and sensation form the vestibular nucleus
293
what is the rhomboid fossa in relation to the ventricles
the diamond shaped floor of the 4th ventricle
294
what is the area postrema involved with
it is a site associated with nausea control - chemoreceptor trigger zone
295
what structure does the hypothalamus and thalamus make together
the diencephalin
296
what is the function of the fornix
connects the hippocampus with the diencephalon and the precommissural septum
297
what is the function of the medial geniculate body
to relay auditory information from the midbrain to the auditory cortex
298
what is the function of the lateral geniculate body
relays visual information from the optic nerve to the visual cortex via the optic radiations
299
what are association fibres
they link cortical regions within the same hemisphere
300
what are commissural fibres
these link similar functional areas of the two hemispheres
301
what are projection fibres
these link the cortex with subcortical structures
302
where is the choroid fissure
it is a narrow cleft between the thalamus and the fornix
303
what happens in a limbic system lesion
can results in anterograde amnesia, generation of emotions and emotional responses in the absence of stimuli, production of inappropriate emotional responses, inability to detect emotional response in others
304
what is hydrocephalus
a blockage of CSF flow in the ventricles or subarachnoid space leading to a rise in fluid pressure causing the ventricles to swell
305
what is the insular cortex of the basal ganglia responsible for
taste and interception
306
what separates the thalamus from the lentiform nucleus
the internal capsule
307
what are the constituents that comprise the basal ganglia
the globus pallidus, the internal capsule, the caudate nucleus, the putamen, the substantia nigra, the subthalamic nucleus
308
where do the ribs bind onto the thoracic vertibrae
the costal facets
309
what is the uppermost part of the spinous process that is palpable
C7
310
where in the spine is rotation at a maximum
thoracic region
311
where in the spine is there the most limited rotation
the lumbar region
312
where is there the least flexion and extension in the spine
thoracic region - due to the ribs
313
what are the two parts of the intervertebral discs
the nucleus pulposus which is surrounded by the annulus fibrosus
314
what two structures is the annulus fibrosus attached to
the vertebral body and the posterior longitudinal ligament
315
what is found on the outer edges of the intervertebral discs
hyaline cartilage
316
what does the ligamentum flavus connect
The ligamenta flavum is a short but thick ligament that connects the laminae of adjacent vertebrae from C2 to S1
317
what happens during spinal herniation
the annulus fibrosus no longer contains the nucleus pulposus and it bilges into the spinal canal/intervertebral foramina and compresses the nerve
318
what spinal region is the most common for herniation
the lumbar region
319
what is the epidural space (spine)
space between the vertebrae and the dura mater
320
what are the segments of the spinal nerves
31
- 8 cervical
- 12 thoracic
- 5 lumbar
- 5 sacral
- 1 coccyx
321
where does the posterior longitudinal ligament of the spine connect
The posterior longitudinal ligament connects and stabilizes the bones of the spinal column. It runs almost the entire length of the spine, from the 2nd vertebra in the cervical spine (neck) all the way down to the sacrum (end of the spine). The ligament is adjacent to the spinal cord.
322
what is the function of the interspinous ligament of the spine
thin and membranous ligaments, that connect adjoining spinous processes of the vertebra in the spine. They extend from the root to the apex of each spinous process. They meet the ligamenta flava in front and blend with the supraspinous ligament behind.
323
what is the function of the supraspinous ligament
connects together the apices of the spinous processes from the seventh cervical vertebra to 3rd or 4th lumbar vertebrae. the role of the interspinous ligament is to limit flexion (bending forwards) through restricting separation of the spinous processes of the vertebral column
