A&P 1: Lower Brain/Cerebrum/CNs Flashcards
1
Q
What are the 4 parts of the diencephalon?
A
Thalamus
Hypothalamus
Epithalamus
Subthalamus
2
Q
What supports the largest part of the brain?
A
Diencephalon and brain stem support the cerebrum
3
Q
What are the two layers of the cranial dura mater?
What makes these layers?
A
External periosteal- formed by periosteum covering the internal surface of the cranium
Internal meningeal- continuous w/ dura mater of the spinal cord
4
Q
The two layers of the cranial dura mater are fused together except for where?
A
Separate to enclose the dural venous sinuses
5
Q
What is the function of the dural venous sinuses?
A
Drain blood from brain to the internal jugular vein
6
Q
What are the 3 extensions of the dura mater?
A
Falx cerbri- cerebrum hemispheres
Falx cerebelli- cerebellum hemispheres
Tentorium cerebelli- cerebrum and cerebellum
7
Q
Brain consumed __% of the body’s O2 and glucose
A
20%
8
Q
Neurons synthesize ATP almost exclusively from ____
A
Glucose
9
Q
What are the parts of the brain that lack the BBB?
A
Pineal gland
Pituitary gland
Medial eminence of hypothalamus
10
Q
What part of the brain senses toxins in the blood and is responsible for control over vomiting?
A
Area postrema (4th ventricle)
11
Q
What can pass into the BBB by active transport?
A
Water soluble
Glucose
12
Q
What crosses the BBB very slowly?
Not at all?
Easily?
A
Slowly: Creatinine, urea, ions
Not: proteins, ABX
Easily: O, CO2, ETOH, anesthetics
13
Q
What space does CSF circulate through?
A
Subarachnoid space
14
Q
What separates the lateral ventricles?
A
Septum pellucidum
15
Q
What surrounds the 3rd ventricle?
A
R/L halves of thalamus
16
Q
What surrounds the 4th ventricle?
A
Brain stem
Cerebellum
17
Q
Where is the CSF made and by what type of cells?
A
Produced in choroid plexuses by ependymal cells
18
Q
How do ependymal cells make CSF?
A
By filtration (some secretion)
19
Q
What is the sequence of CSF flow from lateral ventricles -> circulation?
A
Lateral ventricles Interventricular foramina 3rd ventricle Aqueduct 4th ventricle Median (1) and lateral (2) apertures Subarachnoid space
20
Q
How can hydrocephalus develop in adults?
A
Head trauma
Meningitis
Subarachnoid hemorrhage
21
Q
Define reticular formation
A
Gray and white matter network that spans throughout brain stem
22
Q
What processes/reflexes does the medulla oblongata control?
A
Breathing
HR
BP
Cough
Swallow
Vomit
23
Q
Where does the medulla oblongata start?
A
Foramen magnum
24
Q
What color matter is found in the medulla oblongata?
A
White w/ ascending and descending tracts
25
Define pyramids and their functions
```
Bulges of white matter on ANTERIOR
Corticospinal tracts (largest motor tracts from cerebrum->spine)
```
26
Define decussation and where it occurs?
Axons of L pyramid cross to R side of pyramid
27
Medullary nuceli are what color matter?
Gray
28
What are the 3 masses in the medullary nuclei
Cardiovascular
Medullary rhythmic
Deglutition
29
What is the function of the cardiovascular center?
Heart rate and force
| Vessel diameter
30
What is the function of the medullary rhythmic center?
Adjusts basic rhythm of breathing
31
Function of the inferior olivary nucleus
Relay impulses from cortex, red nucleus and spinal proprioceptors to cerebellum
32
What nucleus' make up the posterior nuclei?
Gracile and cuneate nucleus
33
What are the functions of gracile and cuneate nucleus
Touch
Conscious proprioception
Pressure
Vibration
34
Where are the first and second order sensory neurons and where do the relay impulses to?
First order- bodies in dorsal root of spinal cord
Second order- bodies in correspondingly named posterior nucleus of medulla
First order->posterior columns->Posterior nuclei->second order->medial lemnisus in thalamus
35
What is the name of the white band in the thalamus?
Medial lemniscus
36
The medial lemniscus extends through what 3 structures?
Medulla
Pons
Midbrain
37
Define posterior column-medial lemniscus pathway?
Tracts of posterior columns +
| Axons of medial lemniscus
38
Where do pontine nuclei relays signals to? What type of signals are these?
Voluntary muscle movements from cortex->cerebellum
39
What are the two structures in the pontine that help control breathing?
Pneumotaxic center
| Apneustic area
40
What are the components of the respiratory center?
Medulla- rhythmic
Pons- pneumotaxic
Pons- apneustic
41
What are the two parts of the medullary rhythmic area?
Inspiratory and expiratory area
42
What happens when the inspiratory center is active?
Generates nerve impulses to: EXTERNAL intercostal muscles
| diaphragm
43
During normal, quiet breathing and in the absence of the inspiratory center, what event occurs?
Exhalation, passive recoil of lungs and thoracic wall
44
What center is inactive during quiet breathing?
Expiratory
45
What happens with the expiratory center during forceful breathing?
Expiratory area sends impulses to INTERNAL intercostal and abdominal muscles
46
What contribution does the pneumotaxic and apneustic area make during respiration?
Pneumotaxic- turn inspiratory area off (prevents over expansion)
Apneustic- prolongs inhalation by sending impulses to inspiratory area
47
CN 8 has nuclei in what two parts of the brain stem?
Pons
| Medulla
48
What are the two sensory branches of CN8
Vestibular- sensory axon ending in pons
| Cochlear- sensory axons ending in medulla
49
How does the vestibular branch of CN8 enter the cerebellum?
Inferior cerebellar peduncle
50
What are the motor axons of CN*?
Project from pons to hair cells in semicircular canals and spiral organ
51
What is the function of the mesencephalon?
Connects the pons to the diencephalon
52
What types of impulses does the cerebral peduncles conduct?
Corticospinal
Corticobulbar
Corticopontine
53
What does the tectum contain?
Two rounded elevations, corpora quadrigemina
54
The Corpora Quadrigemina comprised of what two structures?
Superior colliculi
| Inferior colliculi
55
Function of superior colliculi
Extrinsic eye movement during eye tracking
Pupil reflex
Accommodation reflex
56
Function of the inferior colliculi
Relays impulses from inner ear to thalamus
Startle reflex
57
Function of the Substantia Nigra
Releases dopamine
| Controls subconscious muscle activities
58
What structure of the brain is effected by Parkinson's disease?
Substantia Nigra
59
Function of the Red Nuclei
Coordinate muscle movements
60
Why is the Red Nuclei red?
Rich blood supply
| Iron containing pigment in neuron cell bodies
61
Where does the rubropsinal tract originate?
Red nucleus
62
What does the Red Nucleus control?
Baby crawling
Arm swings during walking
Upper shoulder/arm muscles
63
What controls the fine/precise movements of fingers?
Corticospinal tract
64
What is the main function of the Reticular Formation?
Main function: regulates muscle tone
| RAS: Maintain consciousness, awakening from sleep
65
What is the vermis and where is it found?
Central constricted area of the cerebellum
66
Define folia and where are they found?
Ridges on surface of cerebellum
67
What are the components of the cerebellar cortex?
Gray matter w/ foliar ridges
| White matter forming the arbor vitae
68
Function of the cerebellar peduncles?
Conduct impulses between cerebellum and brain
69
Difference between Cerebral Peduncles and Cerebellar Peduncles?
Cerebral: anterior, impulses from cerebrum to spine
Cerebellar: posterior, impulses from cerebellum and brain
70
Main function of the cerebellum?
Evaluate how well movements are carried out
Posture
Balance
71
Function of the anterior/posterior lobes of cerebellum?
Unconscious refinements of skeletal muscle movements
72
Function of the floculonodule lobe of the cerebellum?
Equilibrium and balance
73
Define ataxia
Without order, incoordination
74
Ataxia is contributed to what issues in the cerebellum?
Infection
Injury
Disease
Degeneration
75
How does alcohol effect the brain and potentially cause death?
Inhibits cerebellum
| Suppresses medullary rhythmicity
76
Diencephalon surrounds which brain ventricle?
3rd
77
Where does the deincephalon extend from/to?
From brain stem to cerebrum
78
What makes up most of the diencephalon?
Thalamus
79
What connects the two halves of the thalamus?
Intermediate mass
80
What are the functions of the thalamus?
Main relay station for sensory impulses
Autonomic activities
Maintenance of consciousness
81
What is the function of the Internal Capsule?
Band of thick white matter
| Separates thalamus and caudate nucleus from lentiform nucleus
82
Function of the Mammillary bodies?
Relay station for olfactory reflexes
83
What is the main visceral control center of the body?
Hypothalamus
84
Hypothalamus receptors monitor what things?
Glucose
Osmotic pressure
Blood temp
Hormones
85
What are the specific functions of the hypothalamus?
```
ANS
Hormone production
Emotion
Behavior
Eating
Drinking
Body temp
Cardiac rythms
States of consciousness
```
86
Parts of the epithalamus and their function?
Habenular nuclei- emotional olfactory responses
| Pineal gland- melatonin secretion
87
What does the subthalamus contain?
Tracts
| Paired subthalamic nuclei
88
What are the layers of matter in the cerebral cortex?
Gray->white->gray nuclei
89
What is the most prominent fissure?
Longitudinal fissure- separates cerebrum into R/L hemispheres
90
When are gyri and fissures developed?
Embryonic development
| When gray matter of cortex enlarges faster than the deeper white matter
91
Define central sulcus
Separates the frontal and parietal lobes
92
Define the lateral cerebral sulcus
Separates frontal and temporal lobes
93
Define parieto-occiptal sulcus
Separates the parietal and occipital lobe
94
Define association tracts
Nerve impulses between gyri in same hemisphere
95
Define Commissural tracts
Nerve impulses between gyri across different hemispheres
96
Define Projection tracts
Nerve impulses from cerebrum to lower CNS / lower CNS to cerebrum
97
What are the important groups of commissural tracts?
Corpus callosum
| Anterior/posterior commissure
98
What makes up the basal ganglia?
Globus pallidus
Putamen
Caudate nucleus
99
What makes up the Lentiform nucleus?
Globus Pallidus
| Putamen
100
What makes up the Corpus Striatum?
Lentiform and Caudate nucleus
101
Why is the Basal Ganglia a naming exception?
Ganglia usually used for collections of nerve cell bodies outside of CNS
102
What does the basal ganglia help regulate?
Initiation and termination of movements
Control conscious contractions of skeletal muscles
Muscle tone
103
Define inconscient
Unconscious
104
What movement disorders affect the basal ganglia?
Parkinsons- melanin-pigmented dopamine producing neurons of basal ganglia degenerate
Huntingtons- damage to corpus striatum
105
What happens if the basal ganglia is damaged?
Tremors
Stiffness
Involuntary movements
106
Basal ganglia damage has bee linked back to what disorders?
OCD and ADHD
107
What is the Limbic system?
Emotional, affective brain
108
What is the "emotional brain"?
Limbic system
109
What does the Limbic system play a primary role in regulating?
```
Pain
Pleasure
Docility
Affection
Anger
```
110
Where does the Limbic system tie into other brain structures?
Encircle upper part of brain stem
111
What are the components of the limbic system?
```
Hippocampus
Amygdala
Limbic lobe
Dentate and Cingulate gyrus
Mammillary bodies
Anterior/medial thalamus nuclei
Olfactory bulbs
Fornix
```
112
What is the role of hippocampus?
Converting new info->long term memories (autobiographical and factual)
The memory "gateway"
113
What does the amygdala play roles in?
Docile behavior
Rage
Aggression- presence or absence
Restlessness
114
What do the olfactory bulbs synapse with?
Olfactory receptors
115
What are the olfactory relay stations?
Mammillary bodies
116
What is the location and function of the Cingulate Gyrus?
Superior to Corpus Callosum
| Sensory input w/ emotions, regulates aggression and mediates emotional response to pain
117
What is the function and location of the Fornix?
Extends from hippocampus to mammillary body of hypothalamus
Forms arch over thalamus
Carries signals hippocampus->hypothalamus
Transfers info mammillary bodies->hippocampus
118
What happens if the hippocampus is damaged?
Anterograde amnesia- inability to generate new memories
119
What is the "executive suite" of the brain?
Cerbral cortex
120
What are the functions of the Cerebral Cortex?
```
Communicate
Perceive
Remember
Understant
Appreciate
Initiate voluntary movement
```
121
What type of matter makes up the Cerebral Cortex?
```
Gray matter only
Neuron bodies, dendrites and unmyelinated axons
Glia
Vessels
NO FIBER TRACTS
```
122
What is each hemisphere of the brain mainly concerned with?
Contralateral sensory and motor functions
123
Generally, there is _____ of cortical function
Lateralization (specialization)
124
Define association areas
Communicate w/ motor cortex and association areas to analyze, recognize and act on sensory inputs
Receive input from primary's and integrate sensory experiences to generate patterns of recognition/awareness
125
Define Primary Sensory Areas?
Receives impulses from sensory neurons w/out prior filtering/analysis
126
Define Primary Motor area?
Originators of voluntary muscle contractions
127
What is located in Areas 44/45 of the Frontal Lobe and what function does it have?
Broca's Speech Area
Planning and production of speech
Nerve impulses->premotor regions
128
What is located in Areas 22, 39/40?
Wernicke's Area
| Interprets and recognizes spoken words
129
Define aphasia
Inability to use or comprehend words
130
What hemisphere contains the language areas?
L hemisphere
131
What occurs if there is damage to Broca's Area?
Non-fluent aphasia- inability to form words (know what to say, can't say it)
132
What happens if there is damage to Wernicke's Area?
Fluent aphasia
| Produces strings of words w/out combined meaning
133
People with fluent aphasia may exhibit what two forms?
Word deafness- inability to understand spoken words
Word blindness- inability to understand written words
Or, both
134
What functions are predominantly controlled by the LEFT hemisphere?
Language
Math
Logic
135
What functions are predominantly controlled by the RIGHT hemisphere?
Visual-spatial skills
Intuition
Emotion
Art/music appreciation
136
Define hemispheric lateralization
Functional asymmetry between the brain hemispheres
137
What are the suspected causes of Alzheimers
Genetics
Environment
Lifestyle
Aging process
138
What anatomical changes are found in a brain with Alzheimers upon autopsy?
Loss of neurons that release ACh
Destruction of neurons at nucleus basalis
Beta-amyloid plaques
Neurofibrillary tangles
139
What is the hallmark sign/finding of Alzheimers in a brain?
Neuron destruction at nucleus basalis
140
Define concussion
Brain injury w/ loss of consciousness
Vision disturbances
Issue w/ equilibrium
THE MOST COMMON BRAIN INJURY
141
Define contusion
Bruising of the brain due to trauma (concussion)
142
Define Free Radical
Charged molecule w/ unpaired ve-
143
Define hematoma
Localized, clotted pool of blood
144
Define ischemia
Reduction of blood flow
145
Define laceration
Tear of the brain, rupture of large vessels
146
Define cerebrovascular accident
Stroke
| Usually caused by intercerebral hemorrhage, emboli or atherosclerosis of cerebral arteries
147
Define Transient Ischemic Attack
Impaired brain blood flow causing episode of temporary cerebral dysfunction
148
Define agnosia
Inability to recognize significance of sensory stimuli (sounds, sights, smells)
149
Define apraxia
Inability to carry out movements in absence of paralysis
150
Define lethargy
Functional sluggishness
151
Define Reye's Syndrome
Effects brain and liver after viral infection (chicken pox, influenza)
Most often in kids/teens who take aspirin
152
Define stupor
Unresponsiveness that can be aroused for brief moments w/ vigorous stimulation
153
What are the only two "only" sensory neurons?
1 and 2
154
What are nerves are grouped as the sensory nerves?
1 2 8
155
What nerves are grouped together as motor nerves?
3 4 6 11 12
156
What is the sensory function of the primary motor nerves?
Proprioception
157
What nerves are termed as "mixed" nerves?
5 7 9 10
158
What two CNs only innervate one muscle?
4- superior oblique
| 6- lateral rectus
159
Which motor neurons also have autonomic axons?
3 7 9 10
160
Motor neurons w/ autonomic nerves are part of what branch of NS?
What do they innervate?
Parasympathetic
| Innervate glands, smooth muscle and cardiac muscle
161
What type of neurons are olfactory receptors and optic nerves?
Bipolar
162
How do olfactory axon bundles form olfactory nerves?
Extend through cribiform plate of ethmoid bone
163
Define anosmia
Loss of sense of smell
164
CN 2 axones are myelinated or unmyelinated?
Myelinated
165
What is the sequence of terms from the retina to the occipital lobe?
```
Rods/cones
Ganglion cells
Retina
Optic nerve
Optic chiasm
Optic tract
```
166
What extrinsic and intrinsic muscles does CN 3 innervate?
Extrinsic eye muscles not innervated by CN 4 and 6
Intrinsic: ciliary muscle and sphincter pupillae (parasympathetic)
167
What muscle does CN 3 innervate in the eye lid?
Levator palpebrae superioris
168
What is the smallest and largest CN?
Smallest- 4
| Largest- 5
169
What is unique about CN 4?
Only CN to arise from posterior aspect of brain stem
170
What muscle dos CN 4 innervate?
Superior oblique muscle
171
CN4 moves the eye in which directions?
Inferior and lateral
172
Having a PT track a finger with their eyes utilizes which CNs?
3 4 and 6
173
Where does CN 5 emerge from?
Pons, isolated from other CNs
174
What does CN5 provide sensory and motor?
Sensory: face, scalp and anterior 2/3 of tongue
Motor: chewing
175
What are the two roots and subsequent branches of CN5?
```
Small root- mastication
Large root- sensation
Ophthalmic nerve (V1)
Maxillary nerve (V2)
Mandibular nerve (V3)
```
176
What part of the facial nerve is the target for dental procedures?
Maxillary nerve
177
What nerve contains the corneal reflex?
CN V1
178
What CN is the dermatome for the face and scalp?
CN 5
179
What muscle does CN 6 innervate?
| What kind of movement does it provide?
Lateral rectus
| Abduction
180
CN 7 allows for what types of movements, sensory, and autonomic processes?
```
Movement:
Facial expression
Stylohyoid
Posterior belly of digastric
Satpedius muscles
```
Sensory:
taste buds on anterior 2/3 of tongue
Parasym: lacrimal, nasal and salivary glands (sublingual and submandibular)
181
What are the 5 branches of the facial nerve?
```
Temporal
Zygomatic
Buccal
Mandibular
Cervical
```
182
Function of CN8?
Vestibular branch: equilibrium
| Cochlear: hearing
183
Function of CN 9?
Sensory: posterior 1/3 tongue taste and sensation
Baroreceptors
Chemoreceptors
Motor fibers to parotid gland
184
Where is the carotid sinus and what does it contain?
Internal carotid artery
| Contains carotid body (chemoreceptors) that react to changes in O, CO2 and H+
185
Having a PT open their mouth, protrude their tongue and saying "AHH" uses which CNs?
9 and 10
186
What is the longest CN?
10
187
Short function of CN 10?
```
Swallow
Talk
Cardiac
GI tract
Respiration
Taste
```
188
Where is the Vagus nerve distributed in?
Head
Neck
Thorax
Abdomen
189
What are the sensory and motor functions of CN10?
```
Sensory:
taste
touch
pain
temp
proprioception(epiglottis, pharynx)
BP
O/CO2
```
Motor:
Swallow
Cough
Voice production
Autonomic:
GI smooth muscles
Slows HR
Secretes digestive fluids
190
What type of procedure can be done to reduce stomach acid secretions/reduce stomach ulcers?
Selective vagotomy
191
Why is CN11 sometimes called the spinal accessory?
Originates from both brain stem and spinal cord (only CN w/ spinal cord component)
192
Functions CN11 allows?
Swallowing
Trapezius
Sternocleidomastoid
193
What CN allows for pharynx, larynx, shoulder and neck muscle movements?
CN 11
194
What muscles does CN 12 innervate?
All intrinsic and extrinsic muscles of the tongue EXCEPT palatoglossus
195
What muscles are needed for balanced tongue protrusion?
Genioglossi muscles
196
Spinal cord is an extension of what part of the brain?
Medulla oblongata
197
Where does the spinal cord start and end?
Foramen magnum
| Conus medullaris @ L1/L2
198
Where does the dura mater start and extend to in the spine?
Foramen magnum
| S2
199
Where is the epidural space?
| What does this space contain?
Between dura mater and wall of vertebral canal
| Fat and CT
200
Where is the subdural space and what does it contain?
Between dura and arachnoid mater
| Contains Interstitial fluid
201
What layer of the spinal meninges contains the blood and lymph vessels?
Pia
202
What is the subarachnoid space filled with?
CSF
203
Define denticulate ligaments
Extensions of Pia Mater, fuse w/ arachnoid and inner surface of dura mater
204
What is the function of denticulate ligaments
Suspend spinal cord w/in dural sheath and protect it from displacement
205
Define arachnoid trabeculae
Strands originating from arachnoid mater connecting arachnoid to pia mater
206
Where does the spinal cord in adults start and end?
Medulla oblongata
| S2
207
What are the purposes of the cervical and lumbar enlargements
Accommodate nerves to/from limbs
208
Where is the conus medullaris?
Inferior to lumbar enlargement
| Ends at L1/L2
209
Define filum terminale
Extension of pia mater that anchors spinal cord to coccyx
210
Define cauda equina
Nerves that leave the spinal cord but don't leave the vertebral column so continue in vertebral canal in strands
Only in L/S/C regions
211
Where is a spinal tap conducted?
L3/L4 or L4/L5
212
What are the 6 uses of a spinal tap?
```
Withdraw CSF
ABX
Contrast
Anesthetics
Chemo
Measure CSF pressure
```
213
__ bundles of axons connect each spinal nerve to a segment of cord
2 bundles
214
Each bundle of axons is called a ____ which is composed of smaller units called _____
root
| rootlet
215
What is the swelling each posterior and anterior root has?
Posterior root ganglion
| Anterior root and rootlets
216
Posterior root ganglion contain cell bodies of _____
Sensory neurons
217
Anterior roots contain axons of ______
Motor neurons (CNS to effectors)
218
Gray matter in spine is shaped like a ___
H, butterfly
219
What forms the crossbar of the H in the spinal gray matter?
Gray commissure
220
What do the anterior horns of the spinal column contain?
Cell bodies of somatic neurons
Motor nuclei
Provide impulses for skeletal muscle contractions
221
What do the posterior horns of the spinal column contain?
Somatic and autonomic sensory nuclei
222
Where does the central canal of the spinal column start?
Continuous w/ 4th ventricle in medulla oblongata
223
Where is the white commissure in relation to the gray commissure?
White is anterior to gray
224
What do the lateral gray horns of the spinal column contain?
Cell bodies of autonomic motor neurons for regulation of smooth/cardiac muscle and glands
225
Lateral gray horns are only present in what parts of the spine?
T1-L3 and S2-S4
226
What is the function of the spinal gray matter?
Receives and integrates incoming/outgoing information
227
What parts of the spinal cord does polio attack?
Cell bodies of motor neurons in anterior horns
| Nuclei of cranial nerves
228
Anterior and posterior gray horns divide white matter into what three columns?
Anterior
Posterior
Lateral
229
Define tracts
Bundles of myelinated axons with common origin/destination and carry similar info
230
Where does the first cervical pair of nerves emerge from?
Between occipital and atlas
231
Cervical nerves are numbered by the vertebrae ____ them, while T/L/S nerves are numbered by the vertebrae ____ them
Cervical- below
| T/L/S- above
232
Spinal cord elongation stops at what year?
4-5 years old
233
Sequence of nerves leaving the spine and rejoining
Rootlets->roots->spinal nerves->ramus
| Spinal nerve exists only between union of dorsal and ventral roots, subsequent division into rami
234
Define endoneurium
Covers individual axons
235
Define Fascicle
Groups of axons
236
Define perineurium
Wraps around facsicles
237
Define epineurium
Covers entire nerves
238
After spinal nerves pass through intervertebral foramen and branch, the branches are called ____
Ramus
239
What are the terminal branches of spinal nerves?
Rami
240
Function of the Posterior Ramus?
Innervate deep muscles and skin of dorsal surface
241
Function of the Anterior Ramus?
Muscles and structures of limbs and skin of lateral/ventral trunk surfaces
242
Define meningeal branch of the spinal nerve
Reenters vertebral canal to supply vertebrae and asoociated structures
243
Function of rami communicantes
Contribute to trunk ganglia of ANS
244
The ____ rami of spinal nerves do not go directly to the body structures they supply
Anterior
| Form networks of axons called plexus
245
What part of the spine does not have a plexus?
Thoracic
246
Anterior rami of which spinal nerves are the intercostal nerves?
T2-T12
247
What do the anterior rami supply?
Intercostal muscles
Abdominal muscles
Skin over the above muscles
248
Roots arise from ___ ___
spinal cord->trunks->division
249
What are the trunks of the brachial plexus?
| What are the divisions as a result of branching trunks?
Superior, middle, inferior
| Ant/Post
250
What does the cervical plexus supply?
Skin and muscles of head, neck and superior shoulders, chest and diaphragm
251
Where doe the phrenic nerves arise from?
| What do they supply?
Cervical plexus
| Motor fiber for diaphragm
252
What do the brachial plexus supply?
Shoulder
| Upper Limbs
253
What does the lumbar plexus supply?
Anterolateral abdominal wall
External genitals
Part of lower limb
254
What does the sacral plexus supply?
Buttocks
Perineum
Lower limbs
255
What does cutaneous sensation arise from?
Tactile sensation
Thermal sensation
Pain
256
What sensations encompass tactile sensation?
Touch
Pressure
Vibration
Tickling
257
What are the two types of maps of afferent nerves?
Dermatomes
| Peripheral nerve fields (cutaneous nerves)
258
What do the different afferent nerve maps differ?
Plexuses
259
Define dermatome
Area of skin that provides sensory input to CNS via spinal nerves or CN 5
260
Adjacent dermatomes overlap except for where?
Axial lines
261
Shingles is caused by what virus?
Where does the virus hide?
How does it leave it's hidey hole?
Herpes zoster virus (chicken pox)
Posterior root ganglion
Sensory neurons of skin by fast axonal transport
262
What are the two principle functions of the spinal cord in maintaining homeostasis?
Nerve impulse propagation
| Information integration
263
What type of info does the gray and white matter carry?
Gray- receives and integrates incoming and outgoing info
| White- sensory impulses to brain and motor impulses to effectors
264
Difference between discriminative touch and two-point discrimination?
DT= feel what part is being touched
| Two point= distinguish between two touches near each other
265
What structure integrate input?
Interneurons
266
Cerebral cortex has major function in what movements?
Precise, voluntary muscluar
267
Motor output to skeletal muscles travels down the spine in two types?
Direct
| Indirect
268
Define Direct Pathway
Originate in Cerebral Cortex
| Precise, voluntary movement
269
Direct pathway comprises what tracts?
Anterior Cortico
Lateral Cortico
Corticobulbar tract
270
Define indirect pathways
Originate in brain stem or other areas of autonomic movements
Coordinate body movement with visual stimuli, maintain skeletal muscle tone and posture
271
Indirect pathway includes what 5 tracts?
```
Rubrospinal
Tectospinal
Vestibulospinal
Lateral reticulospinal
Medial reticulospinal
```
272
Define reflex
Fast, involuntary, unplanned sequence of actions in response to stimulus
273
What are the two types of reflexes
Innate
Learned
Or bases on site of integration:
Spinal- spine gray matter
Cranial- brain stem
274
Reflex arc includes what 5 structural components?
```
Sensory receptor
Sensory neuron
Integrating center
Motor neuron
Effector
```
275
How does a dendrite or sensory structure response to a stimulus?
Produces graded potential called generator/receptor potential
276
What is the integrating center of a reflex arc?
CNS gray matter
277
What is the purpose of the Stretch Reflex?
Prevents injury from over stretching
278
What type of reflex arc is the stretch reflex?
Monosynaptic, ipsilateral arc
279
What is the sequence of events during the stretch reflex?
Muscle spindle in muscle signals stretch
| Motor neuron activated and muscle contracts
280
What is the stretch receptor?
Muscle spindle in muscle
281
What is the reciprocal innervation of the stretch reflex?
Polysynaptic neuron
| Antagonistic muscle relaxes
282
Define Westphals Sign and
Absence or decrease in patellar reflexes
283
What can cause Westphals Sign?
Receptor damage
Lesion in motor cortex/pyramid tract/dorsal column
Interruption of femoral nerve
284
Define Tendon Reflex
Controls muscle tension by causing muscle relaxation when force becomes too extreme, protects tendon and muscle
285
What kind of reflex arc is the Tendon Reflex?
Polysynaptic, ipsilateral reflex
286
What are the tension receptors?
Golgi tendon organs located in tendons at musculotendon junction
287
What are the events of the Tendon Reflex?
Tendon stretching
Inhibitory neuron stimulated
Motor neuron is hyperpolarized and muscle relaxes
288
What kind of reciprocal innervation does the Tendon Reflex have?
Causes contraction of ipsilateral muscle group
289
Define Flexor (withdrawal) Reflex
Ipsilateral protective withdrawal reflex to avoid pain
| Contraction of flexor muscles
290
What is the Flexor Reflex aka?
Nociceptive withdrawal refelx
291
Define Crossed Extensor Reflex?
Contralateral, maintains balance during flexor reflex
| Extension of one limb and flexion of opposite limb
292
When is Babinski sign normal and why?
Less than 18mon due to lack of myelination in the corticospinal tract
Dorsiflexion of great toe
293
What is a normal Babinski's sign?
No Babinski
| Curling of toes
294
Define the Clasp Knife Reflex?
Stretch reflex
Rapid decrease in resistance when attempting to flex a joint
Caused by tendon reflex of antagonistic muscle
295
What is a positive Clasp Knife Refelex indicative of?
Damage to pyramidal tract
| Upper motor tract neuron lesion
296
What do hyperactive reflexes indicate?
CNS disease
297
What do decreased reflexes suggest?
Damage to spine
Muscle disease
Disease at nueromuscular joint
Loss of sensation
298
Define monoplegia
Diplegia
Paraplegia
Hemiplegia
One limb paralysis
Two limb paralysis
Both lower limbs
Paralysis one sided
299
Define hemisection
Partial transection of spine on R/L side
300
Define areflexia
Loss of reflex function
301
Define myelitis
Inflammation of spinal cord
302
Define myelography
CT/Xray of spine is taken after contract injection to diagnose tumors/herniations
303
Define neuralgia
Pain along sensory nerve
304
Define paresthesia
Abnormal sensation resulting from disorder of sensory nerves
305
Like the Somatic NS, the autonomic NS operates via ___ ___-
Reflex arcs
306
What is the flow of info in and out of the ANS?
Sensory->CNS integrating center->motor
307
What are the sub-branches of the PNS?
S/E/ANS
308
What are the motor parts of the ANS?
Symp and Parasymp
309
Most of the ANS' interoceptors are ____ or ______
Chemoreceptor
| Mechanoreceptors
310
How/when are ANS interoceptor consciously perceived?
Intense activation may produce conscious sensation
311
How does the ANS regulate visceral activities?
Increasing (exciting) or decreasing (inhibiting) activities in effector tissue
312
Unlike skeletal muscles, tissues innervated by the ANS have a _____ function
What does that function mean?
Intrinsic
| Continued function with damaged/lack of serve supply
313
What are the two motor neurons in series of an ANS motor pathway?
Pre-ganglionic: cell body in CNS and is myelinated, extending from CNS to automatic ganglion
Post-ganglion: cell body in ganglion, unmyelinated, extending from ganglion to effector
314
Somatic motor neurons release what neurotransmitter while ANS motor neurons release which ones?
Somatic- ACh only
| ANS- ACh or NorEpi
315
Preganglionic neuron body is located where?
| How does it exit?
Brain or spinal cord
| Exits CNS as part of CN or spinal nerve
316
What kind of nerve impulse does the preganglionic neuron convey?
Impulse from CNS to autonomic ganglia
317
Postganglionic neuron body is where?
Cell body and dendrites are in automatic ganglion
318
What kind of nerve impulse does the postganglionic neuron relay?
Impulse from autonomic ganglia to visceral effectors
319
Preganglion neurons of Sympathetic division have cell bodies located where?
Post ganglion neurons of the parasympathetic division have cell bodies where?
Lateral gray horns of T1-L2
Nuclei of CN 3 7 9 10 and lateral gray horns of S2-S4
320
What are the two major types of sympathetic ganglia?
Sympathetic trunk
| Prevertebral
321
Sympathetic trunk ganglia are aka
Vertebral chain
| Paravertebral ganglia
322
Where are sympathetic trunk ganglia located, what are their functions and sizes?
Vertical rows along spine
Pre- short
Post- long, innervate organs above diaphragm
323
Where are pre-vertebral ganglia located, what are their functions and sizes?
Anterior to spinal column
Pre- short
Post- long, innervate organs below diaphragm
324
What are the 5 major prevertebral ganglia?
Celiac
Superior/inferior
Aorticorenal
Renal
325
Where are parasympathetic trunk ganglia located, what are their functions and sizes?
Pre synapse w/ post in terminal ganglia which are located close to/within walls of visceral organs
Pre- long
Post- short, non-existant
326
What are the parasympathetic ganglia of the head?
Ciliary
Pterygopalatine
Submandibular
Otic
327
Where does the pelvic splanchnic nerves extend to?
Colon
Ureters
Bladder
Reproductive organs
328
Sympathetic ganglia connect w/ postganglion neurons by what ways?
1- synapse w/ first ganglia it meets
2- a/descend then synapse
3- continue through trunk to prevertebral ganglion
4- continue to chromaffin cells
329
What are the projection patters of the sympathetic branch?
Preganglion- many axon collaterals and synapse w/ many postganglion neurons
Postganglion- terminate in several effector after leaving ganglia
330
What phenomenon does the sympathetic branch divergent projection pattern explain?
Why sympathetic response affect entire body almost simultaneously
331
What are the projection patters of the parasympathetic branch?
Preganglion- few axon collaterals and synapse with limited postganglion neurons in the SAME visceral effector
Postganglion- terminate in the same effector after leaving ganglia
332
Where do autonomic plexuses exist?
Thorax
Abdomen
Pelvis
Along major arteries
333
Autonomic plexuses are usually components of autonomic motor pathways, but what can they also contain?
Sympathetic ganglia
Axons of autonomic sensory neurons
Visceral afferent fibers
334
What are the plexuses in the thorax?
Cardiac
| Pulmonary
335
What are the plexuses in the abdomen?
Celiac
| Inf/Superior messenteric
336
What are the plexuses in the pelvis?
Hypogastric
| Renal
337
Characteristics of the cardiac plexus?
Located at base of heart surrounding the large emerging vessels
Supplied by sympathetic post-ganglion and parasympathetic pre-ganglion
338
Characteristics of Pulmonary plexus?
Posterior to each lung
Sympathetic= dilation
Parasymp= constriction and increased secretions
339
Characteristics of the celiac plexus?
AKA solar plexus, largest plexus
Surrounds celiac and mesenteric arteries
Located at last thoracic/first lumbar vertebrae
340
What does the superior/inferior mesenteric plexus supply?
Superior- small and large intestine
| Inferior- large only
341
What does the hypogastric plexus supply?
Bladder
| Genitals
342
What does the renal plexus supply?
Renal arteries
| Ureters
343
Sympathetic preganglionic neurons cell bodies are located where?
Lateral horns of all thoracic and first three lumbar segments
344
How doe sympathetic preganglionic axons leave the spinal cord and vertebral columns?
Spinal cord through anterior root of a spinal nerve
Exit column through intervertebral foramina
345
What preganglionic neurons are myelinated?
Sympathetic
346
How/what joins to form a sympathetic trunk?
Myelinated axons pass through white ramus to enter adjoining paravertebral ganglion
347
White rami communicantes are only present in what spinal regions?
Thoracic
| First 2 lumbar
348
Where does the cervical ganglia emerge from?
T1-T6
349
What does the cervical ganglia comprise of?
Superior/middle/inferior cervical ganglion
350
What do the branches of the cervical ganglia supply?
Superior- head and heart
| Middle/inferior- heart
351
What spinal region receives most of the sympathetic preganglionic axons?
Thoracic ganglia
352
Axons leave the sympathetic trunk in hat 4 ways?
Enter spinal nerves
Cephalic periarterial nerves
Sympathetic nerves
Spanchnic nerves
353
How do sympathetic trunk pathways enter a spinal nerve?
Postganglionic neurons leave trunk through gray ramus and merge w/ anterior ramus of spinal nerve
354
Wha forms sypathetic chains?
Axons collaterals from preganglionic neurons going up or down the sympathetic trunk
355
What type of ganglion axon passes through gray rami communicantes?
Unmyelinated postganglion axon
356
What is the function of gray rami communicantes?
Connects ganglia of sympathetic trunk to spinal nerves
357
What type of rami is associated with all spinal nerves?
Gray
358
What happens to ganglia after synapsing at the cephalic periarterial nerves?
Extend to thoracic cavity to the heart (sup, mid, inferior cervical ganglia and 1-4 thoracic ganglia)
Bronchi and lungs
359
Sympathetic preganglia that pass through the trunk without synapsing form splanchnic nerves that extend to where?
Prevertebral ganglia
360
What type of ganglia make up the splanchnic nerves?
Preganglionic axons that terminate in prevertebral ganglia
361
What does the greater and lesser splanchnic nerve supply?
Greater: liver stomach spleen small intestine and kidney
Lesser: Small intestine and colon
362
What does the lumbar splanchnic nerve innervate?
Colon
Rectum
Genitals
Bladder
363
Adrenal medulla lack what type of ganglion neurons?
What hormones does it secrete?
Postganglionic
Epi
NorEpi
Dopamine
364
Where are parasympathetic preganglion nerve bodie found?
Nuclei of brain stem and lateral horns of S2-S4
365
What does the cranial parasympathetic outflow consist of?
Myelinated preganglion from brain stem in four CNs
366
What does the sacral parasympathetic outflow consist of?
Myelinated preganglion axons in anterior roots of S2-S4
367
Where do parasympathetic preganglion neurons terminate?
Terminal ganglia near organs they innervate
368
Make up of the Ciliary Ganglia?
Posterior aspect of each eye
Preganglion from CN3
Postganglion innervate eye smooth muscles
369
What makes up the Pterygopalatine Ganglia?
Preganglia from CN 7
| Post ganglia to nasal, pharynx and lacrimal glands
370
What makes up the Submandibular ganglia?
Preganglia form CN7
| Postganglia to submandibular salivary glands
371
What makes up the otic ganglia?
Inferior to each foramen ovale
Preganglion from CN 9
Postganglia to parotid salivary glands
372
___% of the total craniosacral outflow is carried by vagus nerve
80%
373
Autonomic neurons are classified into two groups based off the neurotransmitter released, what are the groups?
Cholinergic- release ACh
| Adrenergic- release NE
374
Characteristics of cholinergic neurons
All para/symp Pregang
All parasymp postgang
Symp postgang sweat glands
Somatic NS motor neurson
375
What are Adrenergic neurons?
Symp postgang
376
The only NE neurotransmitter?
Sympathetic Second synapse
377
All cholinergic receptors bind ____
ACh
378
What are the two types of cholinergic receptors?
Nicotinic
Muscarinic
No cross reactivity, both activated by ACh
379
Effects of cholinergic neurons lasts how long?
Brief
380
Activation of nicotinic receptors by ACh causes _______
Depolarization (excitation) of postgang neuron or skeletal muscle
381
ACh activation of muscarinic receptors causes what reactions?
Depolarization or hyperpolarization (inhibition)
GI- relax
Eye- constrict
382
Activation of Muscarinic receptors causes what syndrome?
```
DUMBELS
Defecation
Urination
Miosis
Bronchoconstriction
Emesis
Lacrimation
Salivation
```
383
All adrenergic receptors bind with ?
Both Epi and NE
NE- released by symp postgang
Epi- hormones into blood
384
What are the two types of adrenergic receptors?
Alpha 1 2
| Beta 1 2 3
385
Activation of A1 or B1=____
| Activation of A2 or B2=____
excitatory
| inhibitory
386
Where is B3 receptors and what heppens when activated?
Brown adipose
| Thermogenesis
387
How does NE activity end?
Reuptake
| Enzymatically degraded- COMT or MAO
388
Whta happens with Beta blockers?
B1 receptors predominantly in heart
| Beta blockers reduce effect of epi allowing heart to not work as hard
389
What happens with Alpha blockers?
Located in all blood vessels except heart
| Alpha blockers block adrenergic receptors allowing muscles that constrict to relax
390
What happens when A1 receptors are activated?
Blood vessels and visceral organs constrict
| Pupils dilate
391
Define autonomic tone
| What regulates it?
Balance between symp and parasymp activity
Hypothalamus
392
What structures only receive sympathetic innervation?
```
Seat
Arrectors
Kidneys
Adrenal glands
Spleen
Vessels
```
393
Sympathetic NS is called the E division, meaning?
Exercise
Excitement
Emergency
Embarassment
394
Parasympathetic NS is called the SLUDD, meaning?
```
Salivation
Lacrimation
Urination
Digestion
Defecation
```
395
___ _____ are central in regulating conditions of the body
Autonomic reflexes
396
What is the distal end of a sensory neuron called?
Receptor in an autonomic reflex arc
397
Autonomic sensory receptors are generally ____
Interoceptors
398
Where are the cell bodies of visceral sensory neurons located?
CNs
| Dorsal root ganglia of spine
399
What are the integrating centers for most autonomic reflexes? Some?
Most- hypothatlamus and brain stem
| Some- spinal cord
400
All pregang neurons are____
| All postgang neurons are___
Myelinated
| Unmyelinated
401
The major control and integration center of the ANS is ______?
Hypothalamus
402
Define Raynaud disease
Digits become cold after exposure to cold or stress
Due to excessive sympathetic stimulation to arterioles in digits
403
What does Atropine do?
Anticholinergic
Blocks parasymp
Suppresses salivation
Suppresses resp secretions
Mydriatic agent
Antidote
404
What does Neostigmine do?
Anticholinesterase
Inhibs acetylcholinesterase
Allows ACh to accumulate
Treats myasthnia gravis- skeletal muscle impaired by lack of ACh
405
What do Tricyclic antidepressants do?
Prolong NE on postsynaptic membrane
406
Function of Monoamine oxidase
| Function of MAO inhibitors
Inactivates NE
| MAO inhibitors: prolong NE on postsynaptic membrane
