The Nervous System Flashcards
(342 cards)
1
Q
The nervous system divides into:
A
The peripheral and central nervous system
2
Q
The central nervous system consists of:
A
the brain and the spinal cord
3
Q
The peripheral nervous system consists of
A
- Somatic Nervous System
- Autonomic Nervous System
4
Q
The autonomic nervous system consists of
A
- Sympathetic nervous system
- Parasympathetic nervous system
5
Q
3 main parts of the brain
A
- Cerebrum
- Cerebellum
- Brain stem
6
Q
Subparts of the cerebrum (2)
A
- Telencephalon
- Diencephalon
7
Q
Subparts of the brain stem (3)
A
- Mid brain
- Pons
- Medulla oblongata
8
Q
The brain boasts three poles:
A
- Frontal pole
- Temporal pole
- Occipital pole
9
Q
Telencephalon
A
- largest and most recently evolved area of the brain
- shaped like a boxing glove
- divided into left and right hemisphere by sagittal fissure
10
Q
Horizontal fissure
A
- separates the telencephalon from the cerebellum
- has a lateral fissure which separates the temporal lobe from the upper part of the cerebrum
11
Q
A
Frontal lobe
12
Q
A
Parietal lobe
13
Q
A
Occipital lobe
14
Q
A
Occipital lobe
15
Q
A
Temporal lobe
16
Q
The cortex
A
- the outer covering of the hemisphere
- has many folds
17
Q
A
Pre-central sulcus
18
Q
A
Central sulcus
19
Q
A
Post-central sulcus
20
Q
A
Pre-central gyrus
21
Q
A
Post-centrl gyrus
22
Q
A
Lateral sulcus
23
Q
Components of the diencephalon (4)
A
- thalamus
- hypothalamus
- subthalamus
- epithalamus
24
Q
Thalamus
A
a large nucleus located on both sides of the third ventricle; it is the main sensory nucleus of the brain handling every sense apart from smell
25
Hypothalamus
situated below the thalamus and connected directly to the pituitary gland, which hangs from it
26
Subthalamus
a small nucleus located below the thalamus
27
Epithalamus
another small nucleus located below the thalamus
28
Cerebrum
29
Midbrain
30
Diencephalon
31
Pons
32
Medulla
33
Spinal cord
34
Cerebellum
35
Lateral ventricles
36
Caudate nucleus of the basal ganglia
37
Lentiform nucleus of the basal ganglia
38
3rd ventricle
39
Internal capsule
40
Thalamus
41
Corpus callosum
42
Grey matter of the cerebrum contains:
the cell bodies of the neurons (nerve cells)
43
Basal ganglia (3)
- Lentiform nucleus
- Caudate nucleus
- Amygdala
44
Spinal cord
45
Medulla
46
Pons
47
Midbrain
48
3rd ventricle
49
Corpus callosum
50
Parieto-occipital sulcus
51
Calcarine sulcus
52
4th ventricle
53
3 types of fibers of white matter
- Association fibers
- Commissural fibers
- Projection fibers
54
Association fibers
are for communication within one hemisphere and can be long, short, or intermediate
55
Commissural fibers
are for communication between the hemispheres
56
3 sets of commisural fibers in the brain
- the small anterior commissure
- the tiny posterior commissure
- the huge corpus callosum
57
Projection fibers
- communicate between different levels of the nervous system
- pass from one level of the nervous system to another
58
Describe the pathway fibers of the Pyramidal tract take
fibers pass from the motor cortex, down through the internal capsule, through the cerebral peduncles, through the pons and medulla to the spinal cord and eventually to the spinal level of their target tissue
59
The midbrain has two large fiber bundles
- anteriorly the cerebral peduncles
- posteriorly the paired superior and inferior colliculi
60
Pons
bridges the cerebellar hemispheres
61
Medulla oblangata
- continuous with the spinal cord
- on the anterior sureface are the paired pyramids medially and the olives laterally
62
Cerebellum
- responsible for coordination
- its main connection to the brain stem is via the large middle cerebellar peduncles
63
Cerebellum
64
Inferior colliculus
65
Superior colliculus
66
Midbrain
67
Mammillary body
68
Oculomotor nerve
69
Pons
70
4th ventricle
71
Central canal
72
Medulla
73
Spinal cord
74
Cervical enlargement
75
Lumbar enlargement
76
Conus medullaris
77
Filum terminale
78
Cauda equina
79
The spinal cord extends in the ___________ from the __________ down to _____
- vertebral canal
- foramen magnum
- L 1/2
80
Ventral root
81
Spinal nerve
82
Dorsal root ganglion
83
Dorsal root
84
Posterior horn
85
Intermediate horn (T1-L2)
86
Anterior horn
87
Dorsal funiculus
88
Ventral funiculus
89
Lateral funiculus
90
The anterior horns are responsible for:
motor function
91
The posterior horns are responsible for:
sensory function
92
The ventricular system
The CNS contains a fluid-filled system of chambers known as ventricles and ducts
93
Lateral ventricles
- numerically: ventricles 1 and 2
- anterior horn (in the frontal lobe)
- posterior horn (in the occipital lobe)
- inferior horn (in the temporal lobe)
- body (in the parietal lobe)
94
Atrium of the ventricles
- the wide posterior part of the body joining the posterior and inferior horns
- contain choroid plexuses
- filled with cerebrospinal fluid (CSF)
- connect to the third ventricle via the paired foramina of monro
95
Third ventricle
- thin, sagittally oriented space located between the two halves of the thalamus
- joined to the fourth ventricle by the aqueduct of sylvius which passes through the midbrain
96
Fourth ventricle
- diamond-shaped space between the pons and medulla in front and the cerebellum behind
- is continuous with the central canal of the spinal cord
97
In the fourth ventricle, CSF travels from the ____________ and _________ into the _____________.
Foramina of luschka; foramen of magendie; subarachnoid space
98
Anterior horn
99
Body
100
Posterior horn
101
Inferior horn
102
3rd ventricle
103
Foramen of munro
104
Aqueduct
105
4th ventricle
106
Central canal
107
Foramen of Monro
108
Lateral ventricle
109
4th ventricle
110
Central canal
111
Foramina of Luschka
112
Aqueduct
113
3rd Ventricle
114
Meninges
specialized connective tissue that encases the CNS
115
From outermost to innermost, they three layers of meninges are:
- Dura mater
- Arachnoid mater
- Pia mater
116
Dura mater
- closest to surrounding bone
- invaginates into the sagittal fissure to form the falx cerebri
- invaginates into the horizontal fissure as the tentorium cerebelli
- contains channels: the dural venous sinuses
- covers the brain and extends down the vertebral canal as far as the sacrum
- has a fat-filled space between it and the vertrebral column called the epidural space
117
Arachnoid mater
- contains blood vessels
- invaginates into the fissures and extends a short way into the sulci
- attaches to the pia mater in the cranial vault, creating the subarachnoid space for CSF to circulate
- is firmly attached to the dura in the vertebral column
- is connected to the pia in the verterbal column by the denticulate ligaments
118
Pia matter
- attached to the superficial cortex and to the outer surface of the spinal cord
- is the outer layer of the CNS
119
Skull
120
Pia
121
Arachnoid
122
Dura
123
Pia
124
Denticulate ligaments
125
Arachnoid
126
Dura
127
Dura
128
Falx cerebri
129
Arachnoid
130
Pia
131
Tentorium cerebelli
132
Skull
133
Epidural space
134
Vertebrae
135
Denticulate ligaments
136
Dural & arachnoid
137
Lumbar cistern
138
Choroid plexuses
- produces cerebral spinal fluid in the ventricles from filtered arterial blood
139
CSF circulation
- It passes from the lateral ventricles, through the foramina of Monro to the third ventricle and through the aqueduct to the fourth ventricle and central canal.
- It passes into the subarachnoid space via the foramina of Luschka and Magendie.
- It then circulates all around the CNS in the subarachnoid space, providing a shock absorptive function.
- It eventually passes from the subarachnoid space in the region of the root of the falx. In this region, the arachnoid mater penetrates through the dura into the superior sagittal sinus.
- The CSF can thus filter through the arachnoid villi into the sinus, which is also filled with venous blood.
- The sinuses eventually empty into the internal jugular vein.
140
Superior sagittal sinus
141
Skull
142
Dura
143
Arachnoid
144
Subarachnoid space
145
Arachnoid villus
146
The brain recieves blood from two sources
- the internal carotid arteries
- the vertebral arteries
147
The internal carotid arteries reach inside the skull via the:
carotid canal
148
The vertebral arteries reach the inside of the skull via the:
foramen magnum
149
The vertebral arteries connect to form the;
basilar artery (runs up the pons)
150
The basilar artery divides in two to form the two:
Posterior cerebral arteries
151
Middle cerebral arteries
152
Posterior communication arteries
153
Posterior cerebal arteries
154
Basilar artery
155
Vertebral artery
156
Subclavian artery
157
Brachiocephalic artery
158
Common carotid artery
159
External carotid artery
160
Internal carotid artery
161
Anterior communicating artery
162
Anterior cerebral arteries
163
Anterior cerebral artery
164
Middle cerebral artery
165
Posterior cerebral artery
166
Right internal carotid arteries
167
Right common carotid artery
168
Right subclavian artery
169
Brachiocephalic artery
170
Aortic arch
171
Left subclavian artery
172
Left common carotid artery
173
Vertebral arteries
174
Left internal carotid arteries
175
Basilar artery
176
Posterior communicating artery
177
Anterior communicating artery
178
Functions of the somatic system
- provides voluntary motor control and general sensation information
- consists of 31 or 32 pairs of spinal nerves and twelve pairs of cranial nerves
179
Spinal nerves
exit the spinal cord and the vertebral column through the intervertebral foramina
180
Dorsal root
each nerve has a dorsal root which receives sensory information
181
Ventral root
each nerve has a ventral root which sends motor information
182
Dorsal ramus and ventral ramus
the spinal nerves exit their intervertrbral foramina and split into a small dorsal ramus and a large ventral ramus
183
Dorsal root ganglia
the cell bodies of the sensory nerves are found in the dorsal root ganglia
184
How are the spinal nerves classified?
alphanumerically according to their spinal levels
185
C1-C8
- cervical nerves
- exit above their corresponding vertebrae
186
T1-T12
- thoracic nerves
- exit below their corresponding vertebrae
187
L1-L5
- lumbar nerves
- exit below their corresponding vertebrae
188
S1-S5
- sacral nerves
-exit below their corresponding vertebrae
189
Autonomic system
provides involuntary motor control and visceral sensory perception
190
Major pathways of the somatic nervous system
- Sensory pathways (Ascending)
- Motor pathways (Descending)
191
Sensory modalities (6)
- touch - discriminatory (fine)
- touch - non-discriminatory (crude)
- pain
- temperature
- joint position - proprioception
- vibration
192
Important tracts in the sensory pathway
- dorsal columns
- anterolateral columns
193
Dorsal columns
- carry discriminatory touch, joint position and vibration
- fibers run from below T6 and travel in the fasciculus gracilis
- fibers above T6 travel in the fasciculus cuneatus
- the pathway ascends into the brain stem in the medial lemniscus and synapses again in the thalamus
- the pathway goes through the internal capsule and ends on the postcentral gyrus in the sensory cortex
194
Anterolateral columns
- carries crude touch, pain and temperature sensations
- the second axon of this system crosses over and ascends in the naterolateral tracts
195
Motor pathways
initiate movement in the muscles
196
Tracts of the Motor pathways
- Corticospinal tract
- Other motor tracts
197
Corticospinal tract
- most direct motor pathway
- motor activity is initiated in the motor cortex and the premotor activity
- fibers travel down through the internal capsule, the cerebral peduncles, the pons and then through the pyramids of the medulla
- in the lower medulla, fibers crossover and form the lateral corticospinal tract
- the rest of the fibers remain on the same side to form the anterior corticospinal tract
198
Fasciculus gracilis
199
Fasciculus cuneatus
200
Anterolateral tracts
201
Anterior corticospinal tract
202
Lateral corticospinal tract
203
Dorsal columns
204
T2
205
T8
206
L1
207
L3
208
S1
209
Dorsal columns
210
Nuclei gracilus and cuneatus
211
Fasciculus cuneatus
212
Fasciculus gracilus
213
Lumbar enlargement for lower limb
214
Cervical enlargement (for brachial plexus)
215
Anterolateral spinothalamic tract
216
Medial lemniscus
217
Antero and lateral funiculi
218
Internal capsule
219
Lentiform nucleus
220
Thalamus
221
Corticospinal tract
222
Pyramid of medulla
223
Lateral cortico-spinal tract
224
Anterior track
225
Ventral root
226
Anterior corticospinal tract
227
Decussation of the pyramids
228
CN #1 (Name, Type, Action, Foramen)
- Olfactory
- Sensory
- Smell
- Cribriform plate
229
CN #2 (Name, Type, Action, Foramen)
- Optic
- Sensory
- Sight
- Optic canal
230
CN #3 (Name, Type, Action, Foramen)
- Oculomotor
- Motor
- Eye movement
- Superior orbital fissure
231
CN #4 (Name, Type, Action, Foramen)
- Trochlear
- Motor
- Eye movement
- Superior orbital fissure
232
CN #5 (Name, Type, Action, Foramen (V1, V2, V3))
- Trigeminal
- Both
- Face sensation and muscles of mastication
- V1: Superior oribital fissure
- V2: Foramen rotundum
- V3: Foramen ovale
233
CN #6 (Name, Type, Action, Foramen)
- Abducens
- Motor
- Eye movement
- Superior orbital fissure
234
CN #7 (Name, Type, Action, Foramen)
- Facial
- Both
- Facial expression and taste
- Stylomastoid foramen
235
CN #8 (Name, Type, Action, Foramen)
- Vesibulococlear
- Sensory
- Hearing and balance
- Internal acoustic meatus
236
CN #9 (Name, Type, Action, Foramen)
- Glossopharyngeal
- Both
- Taste and general sensation
- Jugular foramen
237
CN #10 (Name, Type, Action, Foramen)
- Vagus
- Both
- Larynx sense and movement
- Jugular foramen
238
CN #11 (Name, Type, Action, Foramen)
- Spinal accessory
- Motor
- Upper limb movement
- Jugular foramen
239
CN #12 (Name, Type, Action, Foramen)
- Hypoglossal
- Motor
- Tongue movement
- Hypoglassal canal
240
Opthalmic Component (Name, Type, Action, Foramen)
- Trigeminal Nerve V1
- Sensory
- Forehead movement
- Enters via Superior orbital fissure
241
Maxillary Component (Name, Type, Action, Foramen)
- Trigeminal Nerve V2
- Sensory
- Cheek movement
- Enters via Foramen rotundum
242
Mandibular Component (Name, Type, Action, Foramen)
- Trigeminal Nerve V3
- Sensory and motor
- Jaw movement
- Enters/exits via Foramen ovale
243
CN 1
244
Olfactory bulb
245
Olfactory mucosa layer
246
Optic canal
247
Optic tract
248
Optic nerve
249
Optic chiasm
250
Which nerves supplu the extra ocular muscles?
- Oculomotor (CN 3)
- Trochlear (CN 4)
- Abducens (CN 6)
251
Name the extra ocular muscles that CN 3 supplies
- Superior rectus
- Inferior rectus
- Medial rectus
- Inferior oblique
- Levator palpebrae superioris
252
Name the extra ocular muscles that CN 4 supplies
Superior oblique
253
Name the extra ocular muscles that CN 6 supplies
Lateral rectus
254
Midbrain
255
Pons
256
CN 12
257
Medulla
258
CN 11
259
CN 10
260
CN 9
261
CN 8
262
CN 7
263
CN 6
264
CN 5
265
CN 4
266
CN 3
267
Levator palpebrae superioris
268
Superior rectus
269
CN 4
270
Superior oblique
271
CN 2
272
Medial rectus
273
CN 3
274
Inferior rectus
275
Inferior oblique
276
CN 6
277
Lateral rectus
278
Opthalmic Component
279
Maxillary component
280
Mandibular component
281
CN 1
282
CN 2
283
CN 3
284
CN 5
285
CN 7
286
CN 8
287
CN 9
288
CN 12
289
CN 12
290
CN 11
291
CN 10
292
CN 6
293
Explain the general organization of the autonomic pathway
- Each unit of information of the ANS, traveling from the brain to the periphery, utilizes a preganglionic and a postganglionic neuron
- These cells communicate via a synapse in a ganglion outside the CNS
294
Sympathetic nerves arise from:
levels T1 - L2
295
Parasympathetic nerves originate from:
Cranial nerves 3, 7, 9, and 10, and sacral levels S2-4
296
The sypathetic system is also called the
thoracolumbar system
297
The parasympathetic system is also called the
craniosacral system
298
When activated the sympathetic outflow acts: (2)
- to shunt blood away from viscera and into skeletal muscles and sweat glands
- on the adrenal medulla causing the release if epinephrine and norephinephrine into circulation evoking a 'fight or flight' response
299
Autonomic nerves are distributed to two general target tissues:
- the body walls, limbs and superfiical head and neck (which maintain homeostasis in these tissues)
- the organ systems within the torso (thorax, abdomen and pelvic cavities) via the splanchnic nerves
300
Sympathetic preganglionic neurons originate in the __________ qnd exit through the ___________ to join the _______________.
- intermediate horn of the grey matter of the spinal cord (between T1-T2)
- anterior (ventral) root
- spinal nerve
301
Explain somatotopical arrangement
Axons traveling to the superior parts of the body (head, neck, upper limbs) originate in the superior-most portion of the intermediate horn, while those destined for the thorax exit inferiorly and so on until L1-2 where the pelvic, peritoneal and lower limb axons exit
302
Sympathetic trunks
- lie on each side of the vertebral column
- consist of interconnected sympathteic ganglia that run from C1-S5
- The ganglia are arranged somatotopically
- originate on intermediate horn
- has a short preganglionic neuron
303
Superior cervical ganglion
represents C1-4
304
Middle cervical ganglion
represents C5-6
305
Inferior cervical ganglion
represents C7-8
306
Ganglion impar
the most inferior two coccygeal ganglia fuse in midline to form the ganglion impar
307
Nerves to the skin and blood vessels of the limbs, body walls, and superfiical head and neck, always synapse in the:
sympathetic trunk
308
Synaptic nerves destined for body walls leave the spinal nerve via the _______, and then enter the ___________
- white ramus communicans
- sympathetic trunk
309
3 posibilities for the sympathetic nerves destined for body walls
- synapse in the sympathetic trunk ganglion and then exit via the grey ramus communicans to rejoin the spinal nerve
- Travel superiorly to synapse in a higher-level sympathetic ganglion and then leave via the grey ramus communicans to join a spinal nerve
- Travel inferiorly to synapse in the synaptic trunk and then exit via the grey communicans to join the spinal nerve
310
Splanchnic nerves travel to
organs (viscera)
311
4 possible pathways that the preganglionic component of the splanchnic nerves must follow:
1. Synapse at its own level and go directly to the appriopriate plexus (lungs and some heart innervation)
2. Travel superiorly in the trunk to synapse (head and neck and rest of the heart)
3. Descend to the inferior lumbar and sacral level to synapse (bladder and reproductive organs)
4. Pass through their corresponding sympathetic ganglion and emerge anteromedially as the thoracic and lumbar splanchnic nerves before synapsing in the abdominal ganglia or renal ganglia
312
Lateral, Intermediate Grey Horn
313
Sympathetic trunk
314
White ramus
315
Spinal nerve
316
Grey ramus
317
Solid lines represent _____ and dotted lines represent ________
- Solid line represent sympathetic fibers destined for limbs and body walls
- Dotted lines represent fibers destined for viscera or organs
318
The pelvic splachnic nerves arise from ______. These send fibers to the _________, ________, and the __________ and also control blood flow to the _________ or ________
- S2-4
- distal GI tract
- the bladder
- the urethra
- the penis
- clitoris
319
What forms the intramural enteric plexus?
The vagus and pelvic splachnic nerves in the GI tract
320
Greater splanchnics
321
Celiac ganglion
322
Superior mesenteric ganglion
323
Foregut
324
Midgut
325
Sacrum
326
Hindgut
327
Hypogastric plexus
328
Inferior mesenteric ganglion
329
Lumbar splanchnics
330
Lesser splanchnics
331
Sympathetic Innervation of the Eye (Pre-Ganglionic Nerve, Ganglion, Post-Ganglionic Nerve)
- T1
- Superior cervical ganglion
- Intervate with carotid artery to eye and eyelid
332
Sympathetic Innervation of the Heart (Pre-Ganglionic Nerve, Ganglion, Post-Ganglionic Nerve)
- T1-T4
- Trunk gangli C1-T4
- By cardiac splanchnic nerve to cardiac plexus
333
Sympathetic Innervation of the Lungs (Pre-Ganglionic Nerve, Ganglion, Post-Ganglionic Nerve)
- T2-T4
- Trunk ganglia T2-T4
- By splanchnic nerves to pulmonary plexus
334
Sympathetic Innervation of the Foregut (Pre-Ganglionic Nerve, Ganglion, Post-Ganglionic Nerve)
- T5-T9
- Greater splanchnic nerve to celiac ganglion
- Follows branches of celiac trunk to tissue
335
Sympathetic Innervation of the Midgut (Pre-Ganglionic Nerve, Ganglion, Post-Ganglionic Nerve)
- T10-T11
- Lesser splanchnic nerve to superior mesenteric ganglion
- Follows superior mesenteric artery to midgut
336
Sympathetic Innervation of the Hindgut (Pre-Ganglionic Nerve, Ganglion, Post-Ganglionic Nerve)
- L1-L2
- Lumbar splanchnic nerves to inferior mesenteric ganglion
- Follows inferior mesenteric artery to hindgut
337
Sympathetic Innervation of the Adrenal Medulla (Pre-Ganglionic Nerve, Ganglion, Post-Ganglionic Nerve)
- T5-T9
- Greater splanchnic nerve through celiac ganglion to adrenal
- Synapse directly on adrenal medulla cells
338
Sympathetic Innervation of the Kidneys (Pre-Ganglionic Nerve, Ganglion, Post-Ganglionic Nerve)
- T12
- Least splanchnic nerve to synapse in renal ganglion
- Follow renal arteries to kidney
339
Sympathetic Innervation of the Bladder Walls (Pre-Ganglionic Nerve, Ganglion, Post-Ganglionic Nerve)
- T11-L2
- Various ganglia
- Various pathways
340
Sympathetic Innervation of the Bladder Sphincter Vesicae (Pre-Ganglionic Nerve, Ganglion, Post-Ganglionic Nerve)
- T11-L2
- Inferior mesentery ganglia
- Through aorta chain to anterior hypogastric plexus
341
Sympathetic Innervation of the Reproductive System (Majority Case) (Pre-Ganglionic Nerve, Ganglion, Post-Ganglionic Nerve)
- T12-L2
- Synapse at same level
- With least splanchnic nerves down preaortic plexuses to inferior hypogastric plexus
342
Sympathetic Innervation of the Gonads (Pre-Ganglionic Nerve, Ganglion, Post-Ganglionic Nerve)
- T12
- Least splanchnic nerve to synapse in renal ganglion
- Follow gonadal arteries to gonads
