Peripheral Nervous Flashcards
1
Q
Nerves and Scattered Ganglia
A
Cranial Nerves (12)
Spinal Nerves (31)
2
Q
Autonomic Nervous System
A
Sympathetic Nervous System
Parasympathetic Nervous System
3
Q
Special Senses
A
- Eye (Vision)
- Ears (Hearing and Balance)
- Taste and Smell (Chemical Senses)
4
Q
Generalized Sense:
A
Touch
5
Q
Spinal Nerves
A
Axons
Schwann Cells
Connective Tissue
6
Q
Connective Tissue
A
Endoneurium
Perineurium
Epineurium
7
Q
- Bundle of nerve fibers attached to spinal cord
- All are classified as mixed nerves
A
SPINAL NERVES
8
Q
sensory fibers
A
Dorsal root
9
Q
motor fibers
A
Ventral root
10
Q
- Group of nerve fibers from ventral rami of cervical, lumbar and sacral spinal nerves
- is a network of intersecting nerves that serve the same
part of the body
A
Plexuses
11
Q
Plexuses
A
- I. Cervical Plexus
- II. Brachial Plexus
- III. Lumbar Plexus
- IV. Sacral Plexus
12
Q
- Formed by the first 4 cervical nerves (C1, C2, C3, C4)
- This supplies the back and sides of the head and front of the neck with ordinary sensory fibers
- Most important branch is the phrenic nerve composed of motor fibers supplying the diaphragm
A
Cervical Plexus
13
Q
- Lower 4 cervical nerves (C5, C6, C7, C8) and first thoracic (T1),
which supplies the skin and muscles of the upper limb - With branches like the radial, ulnar, and median nerves
- It passes above the first rib posterior to the clavicle and then enters the axilla.
A
Brachial Plexus
14
Q
- From L1 to L4 spinal nerves
- Femoral nerve: supplies muscle and skin on the anterior aspect of the thigh
- Obrutator nerve: supplies muscles and skin of medial aspect of thigh
A
Lumbar Plexus
15
Q
- From L4, L5, S1, S2 and S3 spinal nerves
- The largest branch is called as “Sciatic Nerve”
A
Sacral Plexus
16
Q
T1 – T11 spinal nerves
A
Intercostal Nerves
17
Q
T12 spinal nerves
A
Subcostal Nerves
18
Q
- are 12 pairs of symmetrically arranged nerves attached to the brain
- serve functions such as smell, sight, eye movement, and feeling in the face.
A
Cranial Nerves
19
Q
- Carry impulses towards the brain
- Cranial Nerves: I, II, VIII
A
Purely Sensory Nerves
20
Q
- Carry impulses away from the brain
- Cranial Nerves: III, IV, VI, XI, XII
A
Purely Motor Nerves
21
Q
- Carry both sensory and motor nerve fibers
- Cranial Nerves: V, VII, IX, X
A
Mixed Nerves
22
Q
- Efferent peripheral nerve fibers distributed to smooth muscles, cardiac muscles and glands
A
Autonomic Nervous System
23
Q
Autonomic Subdivisions
A
- Sympathetic
- Parasympathetic
24
Q
- Also called as Thoracolumbar Division
- Actions are directed toward mobilizing the body’s energy for dealing with an increase in activity
A
Sympathetic Division
25
* Also called as Craniosacral Division
* Arises from the 3rd, 7th, 9th and 10th cranial nerves and from the 2nd, 3rd, and 4th sacral segments of the spinal cord
* Action of this division conserve body energies
Parasympathetic Division
26
* Injury to the brain due to involvement of its blood vessels
Cerebrovascular Accident (CVA / Stroke)
27
* Infection of the meninges
Meningitis
28
* Manifestations of an abnormal discharge of nerve impulses from some part of the brain
Seizure Disorders
29
* Increased in CSF pressure
Hydrocephalus
30
* Complete loss of voluntary motor function due to dysfunction of nervous system
Plegia
31
* Weakness of voluntary muscle activity due to dysfunction of nervous system
Paresis
32
* Caused by a virus that damages the anterior horn cells of the cord and the motor nuclei of the cranial nerves
Infantile paralysis (poliomyelitis)
33
Patchy demyelinization in multiple areas of the nervous system involving sensory and motor fibers followed by replacement of the myelin by scarlike plaques
Multiple Sclerosis
34
* Cavitation of the central canal of the spinal cord and excessive multiplication of neuroglia in the gray substance around it
Syringomyelia
35
* Injury to one half of the spinal cord and involving neuronal groups and nerve tracts
J. Brown-Sequard Syndrome
36
* disabling senile dementia, the loss of reasoning and ability to care for oneself
K. Alzheimer’s Disease
37
Outer fibrous layer
sclera and cornea
38
Middle vascular layer or uveal tract
Iris, Choroid and Ciliary Body
39
Inner nervous tissue layer
retina
40
- white of the eye forms the outermost layer of the eyeball
-Consists of a firm fibrous membrane that maintains the shape of the eye
-Gives attachment to the extrinsic muscles of the eye
Sclera
41
-as a clear transparent epithelial membrane
-Light rays pass through the cornea to reach the retina
cornea
42
* Lines the posterior five-sixths of the inner surface of the sclera.
* Very rich in blood vessels
* Deep chocolate brown in color.
* Light enters the eye through the pupil, stimulates the sensory receptors in the retina and is then absorbed by the choroid
Choroid
43
* The anterior continuation of the choroid consisting of ciliary muscle (smooth muscle fibers) and secretory epithelial cells.
* Acts like a sphincter
* Lens is attached to the ciliary body by radiating suspensory ligaments, like the spokes of a wheel
* Supplied by parasympathetic branches of the oculomotor nerve (3rd cranial nerve).
Ciliary Body
44
* Visible colored ring at the front of the eye lying behind the cornea and in front of the lens.
* Composed of pigment cells and two layers of smooth muscle fibers - one circular and the other radiating
* In the center is an aperture called the pupil.
* Parasympathetic stimulation constricts the pupil and sympathetic stimulation dilates it
Iris
45
* Highly elastic circular biconvex body, immediately behind the pupil.
*Thickness is controlled by the ciliary muscle through the suspensory ligament.
*Lens bends (refracts) light rays reflected by objects in front of the eye - only structure in the eye that can vary its refractory power, which is achieved by changing its thickness.
Lens
46
*Innermost lining of the eye
*Extremely delicate structure and well adapted for stimulation by light rays
*Composed of several layers of nerve cell bodies and their axons - sensory receptor cells, rods and cones
Retina
47
*Composed of several layers of nerve
cell bodies and their axons
sensory receptor cells, rods and cones
48
* Near the center of the posterior part is the macula lutea, or yellow spot -little depression called the fovea centralis, consisting of only cones
*small area of retina where the optic nerve leaves the eye is the optic disc or blind spot-no light sensitive cells
Retina
49
Chambers of the eye
* Anterior chamber
* Posterior chamber
50
Anterior chamber
▪Front of lens
▪Filled with aqueous humor
51
Posterior chamber
▪Behind lens
▪Contains vitreous humor
52
▪Skin, muscle, and connective tissue
▪Blinking
✓Prevents surface from drying out
✓Keeps foreign material out of eye
Eyelids
53
▪Eye sockets
▪Form a protective shell around the eyes
Eye orbits
54
Mucous membranes
▪Line inner surfaces of eyelids
Conjunctivas
55
▪Six per eye - move the eyeball
✓Superiorly
✓Inferiorly
✓Laterally
✓Medially
*Extrinsic eye muscles
56
Lacrimal apparatus
▪Lacrimal glands
▪Nasolacrimal ducts
57
▪Lacrimal glands
✓Lateral edge of eyeballs
✓Produce tears
58
▪Nasolacrimal ducts
✓Medial aspect of eyeballs
✓Drain tears into nose
59
cornea, lens, and fluids bend light to focus it on the retina
Refraction
60
impairment of distance vision
▪Eyeball is too long
▪Light focuses anterior to retina
▪ Snellen chart
▪Normal vision
* 20/20
Myopia
61
impairment of near vision
▪Eyeball is shorter
▪Light focused posterior to retina
▪Test using a handheld chart with various sizes of print
Hyperopia
62
▪ Impairment due to aging
▪Loss of lens elasticity
Presbyopia
63
▪ Distinguish shades of gray
▪ Testing
* Pelli-Robson contrast sensitivity chart
* Vistech Consultants vision contrast system
▪ Detect cataracts or retinal problems before sharpness is
impaired
Contrast sensitivity
64
▪ Color-blindness
* May be inherited
* More common in males
▪ Tests
* Ishihara color system
* Richmond pseudoisochromatic color test
▪ Difficulties may indicate retinal or optic nerve disease
Color vision
65
Lazy eye; one eye is not used regularly;
poor depth perception; often concurrent
with strabismus
Amblyopia
66
Cornea or lens has abnormal shape;
blurred images
Astigmatism
67
Opaque structures in lens prevent light
from passing through; vision fuzzy
Cataracts
68
Pink eye; highly contagious bacterial infection
Conjunctivitis
69
Common problem; decreased
production of oil in tears
Dry eye syndrome
70
Inversion of lower eyelid
Entropion
71
Increase in intraocular pressure due to
a buildup of aqueous humor in anterior
chamber
Glaucoma
72
Farsightedness
Hyperopia
73
Progressive disease; inadequate blood supply to
retina; most common cause of vision loss; affects people
over 50 years
Macular degeneration
74
Nearsightedness
Myopia
75
Rapid, involuntary eye movements
Nystagmus
76
Loss of lens elasticity; develops
with age
Presbyopia
77
Layers of retina separate; medical
emergency
Retinal detachment
78
Misalignment of eyes Crossed eyes; one or both eyes
turn inward Wall eye; one or both eyes turn outward
Strabismus
79
Many animals secrete odorous chemicals called
pheromones
80
▪the sensory nerves of smell
Olfactory receptors (Olfactory nerves /first cranial nerves)
81
respond to changes in chemical concentrations
✓Chemicals must be dissolved in mucus - located in the olfactory
organ
✓Stimulate the olfactory chemoreceptors
Chemoreceptors
82
concentrates volatile molecules in the roof of the nose- increases the number of olfactory receptors stimulated and thus perception of the smell.
Sniffing
83
*Inflammation of the nasal mucosa prevents odorous substances
from reaching the olfactory area of the nose, causing loss of the
sense of smell
▪The usual cause is a cold
anosmia
84
*Chemical can stimulate receptors for limited time
*Receptors fatigue and stop responding to chemical
* No longer smell odor
Sensory Adaptation
85
found in the papillae of the tongue
Taste buds contain chemoreceptor
86
Small sensory nerve endings of the glossopharyngeal,
facial and vagus nerves
cranial nerves VII, IX and X
87
where taste is perceived
Parietal lobe of the cerebral cortex
88
How many taste buds are located on the tongue soft plate, pharynx, and larynx
Nearly 10,000
89
A single, long microvillus, projects from each receptor cell to the surface through the taste pore
Gustatory Hair
90
About 12 very large, form a row at the back of the tongue each houses 100-300 taste buds
Vallate Papillae
91
are mushroom shaped and are scattered over the entire surface of the tongue containing about 5 taste buds each
Fungiform Papillae
92
are located in small trenches on the lateral margins of the tongue, ut most of their taste buds degenerates in early childhood
Foliate Papillae
93
The entire surface of the tongue has it and contains tactile receptors but no taste buds
Filiform Papillae
94
serves taste buds in the anterior 2/3 of the tongue
Facial (VII) nerve
95
serves taste buds in the posterior1/3 of the tongue
Glossopharyngeal (IX) nerve
96
Taste cells and supporting structures
* On taste buds
* Supporting structures fill in space
* Taste cells
*Chemoreceptors
*Chemicals in food and drink
must be dissolved in saliva to
activate
97
the process of hearing, is accomplished by the organs of the ear
Audition
98
which uses air to collect and channel sound waves
External Ear
99
which uses a bony system to amplify sound vibrations
Middle Ear
100
which generates action potentials to transmit sound and balance information to the brain
Internal Ear
101
serves taste buds in the throat and epiglottis
Vagus (X) nerve
102
*External ear
* Auricle (pinna)
* External auditory canal
103
*External ear
* Auricle (pinna)
* External auditory canal* Tympanic membrane
* Tympanic membrane
104
* Collects sound waves
Auricle (pinna)
105
* Guides sound wave to tympanic
membrane
External auditory canal
106
* Separates external canal and middle ear
* Vibrates when sound hits it
Tympanic membrane
107
* Middle ear
* Ear ossicles
* Eustachian tube
* Oval window
108
* Ear ossicles
* Malleus
* Incus
* Stapes
109
* Ossicles vibrate in response to vibration of tympanic membrane
Ear ossicles
110
* Connects middle ear to throat
* Equalizes pressure on eardrum
Eustachian tube
111
* Separates middle ear from inner ear
Oval window
112
labyrinth of communicating chambers
Inner ear
113
detect balance of the body
Semicircular canals
114
equilibrium
Vestibule
115
Hearing receptors
Cochlea
116
organ of hearing
Organ of Corti
117
* Startled by loud noises
* Recognize mother’s voice
Infants to 4 months
118
* Regularly follow sounds
* Babble at people
4 to 8 months
119
* Respond to the sound of their name
* Respond to “no
8 to 12 months
120
Effects of Aging to the Ears
*External ear larger / earlobe longer
*Cerumen dryer and prone to impaction
*Ear canal narrower
*Eardrum shrinks and appears dull and gray
* Ossicles do not move as freely
* Semicircular canals less sensitive to changes in position
– affects balance
121
`Effects of Aging to the Ears
*External ear larger / earlobe longer
*Cerumen dryer and prone to impaction
*Ear canal narrower
*Eardrum shrinks and appears dull and gray
* Ossicles do not move as freely
* Semicircular canals less sensitive to changes in position
– affects balance
122
`Effects of Aging to the Ears
*External ear larger / earlobe longer
*Cerumen dryer and prone to impaction
*Ear canal narrower
*Eardrum shrinks and appears dull and gray
* Ossicles do not move as freely
* Semicircular canals less sensitive to changes in position
– affects balance
123
Symptom of a disease, not a normal part
of aging
Hearing Loss
124
Hearing Loss
* Conductive hearing loss
* Sensorineural hearing loss
125
* Interruption in transmission to inner ear
* Causes
* Obstruction of ear canal
* Infection of middle ear
* Reduced movement of stirrup
Conductive hearing loss
126
* Sound waves not perceived by brain as sound
* Causes
* Hereditary
* Repeated exposure to loud noises/viral infections
* Side effect of medication
Sensorineural hearing loss
127
causes damage to sensitive cells in
cochlea
Noise pollution
128
Hearing tests
*Tuning forks
*Audiometer
129
differentiate between types of loss
Tuning forks
130
measures hearing acuity
Audiometer
131
Diagnostic testing
Tympanometry
132
* Measures the ability of the eardrums to move
* Detects diseases and abnormalities of the middle ear
Tympanometry
133
Build up of wax within external auditory canal
Cerumen impaction
134
Deafness
Hearing loss
135
Disturbance in equilibrium characterized by vertigo and
tinnitus
Ménière's disease
136
Inflammation of the ear
Otitis
137
Swimmers’ ear
Otitis externa
138
Middle ear infection; common infection
Otitis media
139
Labyrinthitis; inner ear infection
Otitis interna
140
Immobilization of the stapes; common cause of conductive hearing loss
Otosclerosis
141
Hearing loss due to aging process
Presbycusis
