Download Part Ⅰ The Sensory Organs

山东大学医学院
解剖教研室
李振华
Content
Part Ⅰ The Sensory Organs
2
The Visual Organ
2
The Vestibulocochlear Organ 9
Part Ⅱ The Central Nervous System 17
Introduction 17
The Spinal Cord 20
The brain stem 27
The Cerebellum 36
The Diencephalon 40
The Telencephalon 45
The Nervous pathway 51
The Meninges and Blood Vessels of Brain
60
Part Ⅲ The Peripheral Nervous System 69
The Spinal Nerves 69
The Cranial Nerves 77
The Visceral Nervous System 86
Part IV The Endocrine System 94
1
Part ⅠThe Sensory Organs
Sensory organs include the receptors and accessory organs. The receptors may be divided into
three kinds:
①The exteroceptors: receive stimuli such as touch, temperature, pain, light and sound from
the external environment
②The interoceptors: pick up information about internal environment
③The proprioceptors: receive stimuli from muscles, tendons, joints and ligaments
The Visual Organ
Learning Objectives
You should:

Know the shape of eyeball

Understand the feature, structure and function of the wall of eyeball

Understand the position of the chamber of eye, production and circulation of aqueous
humor

Understand the position and feature of lens and vitreous body

Know the formation and function of the accessory organs of eye (eyelids, sheath of
eyeball, adipose body of orbit)

Understand feature and divisions of the conjunctiva, the position of the lacrimal
gland, the formation of the lacrimal apparatus and its opening, the names and
functions of the extraocular muscles

Know the origin and disbution of the arteries of eye, the branches of the central artery
of retina and the veins of eye.
Composition the visual organ: eyeball and accessory organs of eye
Ⅰ. Shape of eyeball
 Consists of a sphere, approximately 2.5 cm in diameter
 Has anterior and posterior poles
 Equator: an imaginary line encircling the eyeball, midway
between anterior and posterior poles
 Axis of eyeball: a line joining the two poles
2
 Optic axis: a line joining the center of the pupil to the fovea centralis
 The lateral walls are at right angles to each other.
Ⅱ. Wall of eyeball
A. Fibrous tunic of eyeball (outer fibrous layer)
1. Cornea: anterior one-sixth, a nonvascular, transparent
portion, richly supplied by nerves; because it is curved,
the cornea helps focus light
2. Sclera (white of eye, opaque portion): posterior
five-sixths consisting of fibrous connective tissue
that forms a tough protective covering for eyeball,
and containing sinus venosus sclerae which lies beneath the junction of cornea and
sclera for drainage of aqueous humor to venous system
B. Vascular tunic of eyeball (middle vascular layer):
1. Iris
 Thin contractile membrane anterior to ciliary body, with a central opening, the pupil
 Contains sphincter pupillae (circular fibers) and dilator pupillae (radial fibers)
 Partitions anterior and posterior chambers, containing aqueous humor
 Cornea and iris meet to form the iridocorneal angle
Iris
Ciliary body
Ciliary zonule
2. Ciliary body
 Body a ring-shaped thickening anterior to equator, containing smooth muscle fibers
called ciliary muscle
 Ciliary processes: a series of some 60~80 projections producing aqueous humor
 Attached by ciliary zonule to lens
3. Choroid
 Thin, highly vascular in posterior 2/3 of eye
3
 Contains brown pigmented cells and dense capillary plexus
C. Internal tunic of eyeball — retina
1. Pars caeca retinae: lines the ciliary body and iris, nonreceptive and consists merely of
pigment cells
2. Pars optica retinae: lines the choroids, an extension of diencephalon, and extends
forward to ora serrata ; composed of two layers: an outer pigment cell layer and an inner
neural layer, the light-sensitive retina. The ueural layer consists of four layers of nerve
and supporting cells through which light rays must pass to reach the photosensitive cells.
 The fourth layer consists photoreceptor cells
⑴Cone cells are color receptors that function best during the day
⑵Rod cells are dark-light receptors that function best at night and in dim light
 The third layer consists of bipolar neurons, equivalent to cells of dorsal root ganglia
 The second layer is formed ganglion cells, whose axons form the superficial layer of
optic nerve fibers
 The first layer consists of nerve axons that collect at the optic disk and pass through
the sclera to form the optic nerve
 Optic disc (blind spot), located medial to posterior pole of eye, and consists of optic
nerve fibers and central artery of retina
 Macula lutea
⑴ Lies lateral about 3.5 mm to optic disc, a shallow depression, it is completely free
of blood vessels and is yellowish in color
⑵ Fovea centralis, aera of greatest visual acuity (concentration of cones), at its
center
 The pigmentted layer absorbs light that passes completely through the anterior layer,
preventing backscatter (blurring of vision)
Optic disc
Macula lutea
Ⅲ. Contents of eyeball
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A. Aqueous humor
1. Chamber of eye lies between cornea and lens, and divided by iris into anterior and
posterior chambers
2. Production and circulation of aqueous humor: aqueous humor is a clear watery fluid that
fills chamber of eye
 Aqueous humor is continuously secreted by ciliary body into posterior chamber
 It passes through pupil into anterior chamber
 Then it filters though iridocorneal angle into sinus venosus sclerae, this sinus drains
via anterior ciliary veins into ophthalmic veins
Ciliary body
posterior chamber
pupil
sinus venosus sclera
anterior chamber iridocorneal angle
anterior ciliary vein
ophthalmic vein
3. Functions
 Helps focus light
 Helps maintain constant pressure in eyeball
 Helps nourish the lens and cornea
B. Lens
 Transparent biconvex structure, covered by an
elastic transparent capsule
 Located between iris and vitreous body, and suspended behind pupil by ciliary zonule
 Shape changed by the ciliary muscle: for near vision, the ciliary muscle contracts and
the lens rounds up, while for distant vision the lens flattens out, so that the eye may be
focused on distant objects
C. Vitreous body
 Consists of colorless, transparent jelly-like substance in
which there is a meshwork of fine fibrils, occupies the
vitreous chamber, the space between lens and retina
 Helps maintain the shape of eyeball and supports the retina
D. Refractive media: cornea, aqueous humor, lens, and vitreous
body constitute the refractive media of eye which bend entering light waves and focus them
on the retina
Ⅳ. Accessory organs of eye
A. Eyelids
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1. Paired, upper and lower
2. Each consist of following layers, from without inwards:
 Skin, extremely thin
 Subcutaneous areola tissue, loose and delicate
 Muscular layer: orbicularis oculi
 Tarsus, formed by dense connective tissue in which the tarsal glands embedded
 Lined by palpebral conjunctiva
3. Function: to protect, open, and close eye
B. Conjunctiva
1. Thin mucous membrane
2. Three parts
 Palpebral conjunctiva: lining inner surface of eyelids
 Bulbar conjunctiva: lining anterior part of sclera, up to
corneal margin
 Conjuntival fornix (superior and inferior): line of reflection of bulbar and palpebral
conjunctiva
3. Conjunctival sac
C. Lacrimal apparatus
1. Lacrimal gland
 Oval 2-cm, occupies fossa for lacrimal gland
 Ducts (6~10 in number): empty into anterior
region of superior fornix of conjunctiva
 Secrets tears, which move across eyeball to
medial angle,protect and
2. Lacrimal passages: drains tears from eye to nose moisten eye
 Paired lacrimal puncta opening to lacrimal ductules, one on each eylid margin near
medial angle
 Lacrimal ductules: one in each lid, pass medially, join and enter lacrimal sac
 Lacrimal sac within fossa for lacrimal sac, opening into nasolacrimal duct
 Nasolacrimal duct courses 2 cm inferiorly and opens into inferior nasal meatus
3. Tear is produced by lacrimal gland, passes through superior conjunctival fornix into
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conjunctival sac, and then is drained through lacrimal punctum, lacrimal ductule, lacrimal
sac and nasolacrimal duct into inferior nasal meatus.
D. Ocular muscles
There are seven ocular muscles, all of which move the eyeball except levator palpebrae
superioris, which elevates upper eyelid.
Medial rectus
Superior rectus
levator palpebrae superioris
Lateral rectus
Superior obliquus
1. Recti muscles (four)
 Named for their relationship to eyeball: ①superior, ②inferior, ③medial，④lateral
 Arise from common tendinous ring situated at the apex of orbit
 All inserting into sclera posterior to the corneal margin
2. Oblique muscles (two)
 Superior obliquus arises from common tendinous ring , and passes anteriorly, narrows
to a tendon passing through a connective tissue pulley, and then courses posteriorly
and downward, inserts into sclera behind equator
 Inferior obliquus arises from the floor of orbit, inserts into sclera behind equator
Muscles of the eyeballs and eyelids
Muscle
Action
Nerve supply
levator palpebrae superioris
Raises upper eyelid
Ⅲ
Superior rectus
Turns eyeball superomedially
Ⅲ
Inferior rectus
Turns eyeball inferomedially
Ⅲ
Medial rectus
Turns eyeball medially
Ⅲ
Lateral rectus
Turns eyeball laterally
Ⅵ
Superior obliquus
Turns eyeball inferolaterally
Ⅳ
Inferior obliquus
Turns eyeball superolaterally
Ⅲ
E. Connective tissue in the orbit
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 Sheath of eyeball: a thin membrane, which
surrounds the eyeball from optic nerve to
corneoscleral junction, permits the eyeball to
move in the orbit without friction
 Adipose body of orbit: lies between sheath of
eyeball and the orbit acts as a protective
cushion and shock sorber for the eyeball
F. Vessels of eye
1. Ophthalmic artery
 Branch of internal artery
 Branches－central artery of retina
⑴ Enters optic nerve, passes toward the optic disk and then fans out to supply the
retina
⑵Four branches: superior and inferior nasal or temporal arteriole of retina
2. Ophthalmic vein
 Superior ophthalmic vein communicates with facial vein anteriorly, exits posteriorly
via superior orbital fissure to drain into cavernous sinus
 Inferior ophthalmic vein lies on floor of orbit and communicates with pterygoid
plexus, exits via superior orbital fissure to drain into cavernous sinus
Sdudy questions
Ⅰ. Single choice questions (there five choices on each question, only one is correct, please circle
the correct answer):
1．The refractive media of eyeball does not include
A. cornea
B. aqueous humor
C. lens
D. retina
E. vitreous body
2．iris
A. is the largest part of middle tunic
B. divides chamber of the eye into anterior and posterior chambers
C. iris and sclera meet to form angle of anterior chamber
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D. during near vision of light shone on retina the pupil dilates
E. is colourless and transparant
Ⅱ. Multiple choice questions (two to five choices are correct, please circle the correct answers):
1．The muscles turn the anterior pole of eyeball medially include
A. superior rectus
B. superior obliquue
C. inferior rectus
D. inferior obliquue
E. medial rectus
2．Vascular tunic of eyeball includes
A. Cornea
B. Sclera
C. Iris
D. Ciliary body
E. Choroid
Ⅲ. Answer the following questions
1. Write out the name of ocular muscles and nerves innervated the muscles.
2. Describe the feature and structure of the wall of eyeball.
3. Write out the production and circulation of aqueous humor.
The Vestibulocochlear Organ
Learning Objectives
You should:
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
了解前庭蜗器的分部和各部的机能。

了解外耳的组成。掌握外耳道的位置、形态、分部和婴儿外耳道的特点。

掌握鼓膜的形态、位置和分部。

掌握中耳的组成。掌握鼓室的位置、六个壁的主要形态结构及毗邻，并了解其临床意
义。了解听小骨的名称和排列。

掌握咽鼓管的位置、分部、开口部位和作用、幼儿咽鼓管的特点。

掌握乳突窦和乳突小房的位置。

掌握内耳的位置和分部、骨迷路的分部、各部的形态以及骨迷路与膜迷路的位置关系。

了解膜迷路各部的形态与功能。

掌握听觉和位置觉感受器的位置与机能。

了解声波的传导途径。
Ⅰ. General features
A. Organ of hearing and balance
B. Three parts
1. External ear: collects sound waves
2. Middle ear: transmits sound waves
3. Internal ear: contains the vestibulocochlear organ concerned with equilibration and
hearing
Ⅱ. External ear
A. Auricle: a fibrocartilage skeleton, covered by skin
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B. External acoustic meatus
 A slender canal that extends from external acoustic pore to tympanic membrane
(about 2.5 cm length in an adult).
 The lateral third is cartilaginous and the medial two thirds are bony. It is lined by a
layer of thin skin. Ceruminous and sebaceous glands produce cerumen (wax).
 This S-shaped passage medially, at first forward and upward, then backward and,
finally forward and downward.
C. Tympanic membrane
1. A thin oval membrane, about 1 cm in diameter, lying obliquely between external
acoustic meatus and tympanic cavity, faces downwards, forwards and laterally, outer
suface of skin, inner surface of mucous membrane, a concavity toward the meatus,
with a central depression — umbo
2. Two parts
a) Flaccid part: upper 1/4
b) Tense part: lower 3/4
⑴Umbo of tympanic membrane
⑵Cone of light
Ⅲ. Middle ear
A. Tympanic cavity
1. An air-containing cavity locates within petrous portion of temporal bone
2. Walls
a) Roof or tegmental wall formed by tegmen tympani, separates tympanic cavity
from middle cranial fossa
b) Floor or jugular wall separates the cavity from superior bulb of internal jugular
vein
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c) Anterior wall or carotid wall separates tympanic cavity from carotid canal,
superiorly lies two openings:
⑴Upper opening for tensor tympani muscle
⑵Lower opening for auditory tube, which communicates with nasopharynx
d) Posterior wall or mastoid wall
⑴Connected by aditus to mastoid antrum and air cells
⑵Pyramid, a bony projection for attachment of stapedius tendon
e) lateral wall or membranous wall formed by tympanic membrane with
epitympanic recess superiorly
f)
Medial wall or labyrinthine wall separates tympanic cavity from inner ear
⑴ Centrally, a rounded promontory formed by first turn of cochlea
⑵ Fenestra vestibuli covered by base of stapes
⑶ Fenestra cochleae covered by secondary tympanic membrane
⑷ Prominence of facial canal containing the facial nerve
3. Auditory ossicles
a) Consists of chain of three bones: malleus, incus, and stapes.
b) Articulate by synovial joints
c) Transmit vibration of tympanic membrane to footplate of stapes in fenestra
vestibule.
d) Transmission of vibration modified by two small muscles
⑴Tensor tympani dampens vibration of the tympanic membrane
⑵ Stapedius dampens vibration of the stapes
B. Auditory tube
1. About 3~4 cm long, extends from nasopharynx posteriorly, laterally, and upward to
tympanic cavity
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2. Two parts
a) Bony part: posterolateral one-third formed by temporal bone extension of
tympanic cavity
b) Cartilaginous part: medial two-thirds composed of cartilage
3. Functions to equalize air pressure on either side of tympanic membrane
4. In childhood, it is shorter, wider and more horizontal than in adult
C. Mastoid antrum and mastoid cells
1. Mastoid antrum: a small chamber between tympanic cavity and mastoid cells, the
aditus to the antrum connects the mastoid antrum to the epitympanic recess of the
tympanic cavity, the floor of antrum communicates with mastoid cells via several
openings
2. Mastoid cells: contain a group of air cells within mastoid process of temporal bone
Ⅳ. Internal ear
A. General features
1. Lies within the petrous portion of temporal bone
2. Key contents of internal ear
a) Bony labyrinth, a series of bony canal, contains perilymph that suspends the
membranous labyrinth
b) Membranous labyrinth, a system of continuous membranous canals, is filled
with endolymph and contains the sensory organs
B. Parts of bony labyrinth
1. Cochlea, anteriorly
a) It somewhat resembles a snail’s shell
b) Cochlear spiral canal makes two and one-half spinal turns around the modiolus
c) A small shelf of bone, the osseous spiral lamina, protrudes from the modiolus,
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like the thread on a screw
d) Scala vestibuli
⑴ Upper canal of cochlear spinal canal, associated with vestibular wall of
cochlear duct
⑵Contains perilymph, which transmits vibrations from fenestra vestibuli
⑶communicates at apex of cochlea (helicotrema) with scala tympani
e) Scala tympani
⑴ Lower canal of cochlear spinal canal, associated with tympanic wall of
cochlear duct
⑵Contain perilymph, which transmits spent vibrations to fenestra cochleae
2. Vestibule, centrally
a) Hollow bony space
b) Contains utricle and saccule
3. Bony semicircular canals (anterior, posterior, and lateral) posteriorly
a) Semicircular duct in each
b) Canal at right angles to each other
1) The anterior bony semicircular canal is vertically with the long axis of the
petrous portion of temporal bone
2) The lateral bony semicircular canal is nearly horiaontal
3) The posterior bony semicircular canal is paralles to the long axis of the
petrous portion of temporal bone
c) Dilated ampulla in each canal
C. Membranous labyrinth
1. Cochlear duct
a) Enclosed
by
tympanic
wall
and
vestibular wall
b) Contains spinal organ (of Corti), the
sound receptors lies on tympanic wall of
cochlear duct, stimulated by the
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movement of endolymph in the duct
2. Utricle and saccule
a) Membranous sacs in vestibule
b) Connected to each other, cochlear duct, and semicircular ducts
c) Contain macular utricli and macular sacculi, end organs of balance, which
respond to linear acceleration and deceleration, static of gravity
3. Semicircular ducts
a) Contained in bony semicircular canals
b) Contain endolymph
c) Each duct has a membranous ampullae at one end containing crista ampullaris,
receptors of balance that respond to rotational acceleration in three different
planes
Ⅴ. Conduction of sound
A. Air-conduction of sound
1. Auricle collects sound waves
2. Sound waves enter the external auditory canal, strike the tympanic membrane, pass
through the ossicles, strike the fenestra vestibuli, set up waves in the perilymph,
strike the vestibular membrane and scala tympani that transmit vibration to the spinal
organ
3. Hair cells in the spinal organ produce receptor potentials, which elicit nerve impulses
in the cochlear branch of vestibulochochlear (Ⅷ) nerve
B. Bony- conduction of sound
Sound waves → skull → bony labyrinth → perilymph → endolymph within cochlear duct
→ spinal organ
Ⅵ. Internal acoustic meatus
A. Extends from internal acoustic pore to fundus of internal acoustic meatus
B. Facial, vestibulocochlear nerves and vessles of labyrinth pass through the fundus of
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internal acoustic meatus
Sdudy questions
Ⅰ. Single choice questions (there five choices on each question, only one is correct, please circle
the correct answer):
1. Tympanic cavity
can not communicate with outside
The posterior wall is labyrinthine wall
The anterior wall is jugular wall
The inferior wall is mastoid wall
The lateral wall is membranous wall
2. Spiral organ lies in
tympanic cavity
semicircular canals
fenestra vestibuli
basilar membrane (tympanic wall)
cochlear nuclei
Ⅱ. Multiple choice questions (two to five choices are correct, please circle the correct answers):
1. On the labyrinthine wall, there are
A. promontory
B. enestra vestibuli
C. prominence of facial canal
D. fenestra cochleae
E. pyramidal eminenc
2. Receptors of balance contain
A. cochlear duct
B. crista ampullaris
C. macula sacculi
D. macula utriculi
E. modiolus
Ⅲ. Answer the following questions
1. Write out the position, features and divisions of the external acoustic meatus.
2. Describe the feature and structure of the
wall of of the tympamic cavity.
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3. Write out the position and divisions of the internal ear.
Part ⅡThe Central Nervous System
Learning Objectives
You should:

了解神经系统在机体内的作用和地位。

掌握神经系统的区分。

了解神经元的形态结构及分类。

了解神经系统的基本活动方式。掌握反射弧的组成。

掌握神经系统的常用术语
Introduction
Ⅰ. Function of nervous system: a master system in the living body, regulates and integrates the
activities of all the bodily systems for the benefit of the organism as a whole
Ⅱ. Divisions of nervous system
Ⅰ) Central nervous system (CNS)
Telencephalon
Brain
Diencephalon
Cerebellum
Midbrain
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CNS
Brain stem
Pons n.
Medulla oblongata
Spinal cord
Ⅱ) Peripheral nervous system (PNS)
Cranial n. (12 pairs)
PNS
Spinal n. (31 pairs)
Visceral sensory n.
Visceral n.
Sympathetic part
Visceral motor n.
Parasympathetic part
cell body
neurons
dendrites
III. Cellular organization
axon
neuroglia: glial cell
Ⅰ) Structural classification
1. Bipolar neuron: an axon and a dendrite
2. Pseudounipolar neuron: central branch and
peripheral branch
3. Multipolar neuron: an axon and two or more
dendrites
Ⅱ) Functional classification
1. Afferent (sensory) neuron
2. Efferent (motor) neuron
3. Association neuron (interneuron)
Ⅳ. Reflex and reflex arc
Ⅰ) Reflex: a reaction of the organism by the nervous system in response to a stimulus
Ⅱ) Reflex arc: has five basic components
receptor → afferent neurons → CNS → efferent neurons → effector
Ⅴ. Basic terminology in nervous system
Ⅰ) In the CNS
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1. Gray matter and cortex
⑴Gray matter: collection of nerve
cell bodies and their dendrites,
gray color during fresh condition
⑵Cortex: the outermost layer of gray
matter in cerebrum and cerebellum
2. White matter and medulla
⑴White matter: collection of nerve
fibers, white color during fresh condition
⑵Medulla: a central core of white matter beneath cortex of cerebrum and
cerebellum
3. Nucleus: a collection ( group ) of cell bodies which have the same shape and
function
4. Fasciculus ( tract ): a bundle of nerve fibers which have the same origin, termination,
pathway and function
5. Reticular formation: an admixture of cross-crossing fibers with larger or smaller
groups of nerve cells occupying the meshes
B. In the PNS
1. Ganglion: a collection of neuronal cell bodies outside the CNS
2. Nerve: a bundle of nerve fibers held together by connective tissue sheath
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The Spinal Cord
Learning Objectives
You should:

掌握脊髓的位置、外形特点、脊髓节段及其与椎骨的对应关系。

掌握脊髓横切面上灰、白质的配布及各部的名称。

掌握脊髓灰质的主要核团的位置及功能性质。了解脊髓灰质的板层构筑。

掌握脊髓主要上行纤维束（薄束、楔束、脊髓丘脑束）和下行纤维束（皮质脊髓束）
的位置和功能。了解其它上、下行纤维束和固有束的位置及功能。

了解脊髓的功能。了解脊髓损伤后的临床表现。
Ⅰ. Position and external features
Ⅰ) Position
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1.
Lies in vertebral canal
2.
Continuous above with medulla oblongata at level of foramen
magnum and ends below at the lower border of the first lumbar
vertebra in the adult; at birth the cord ends at level of L3
Ⅱ) External features
1.
A long cylindrical structure and slightly flattened anteroposteriorly,
whose lower end tapers into a conus medullaris
2.
Arising from the conus medullaris is the filum terminale, an
extension of the pia mater that extends inferiorly and attaches the
spinal cord to the coccyx. The lumber and sacral nerves develop
long roots that extend as the cauda equina around the filum
terminale.
3. Two enlargements
⑴ Cervical enlargement: corresponds to the C4 to the T1
segments
⑵ Lumbosacral enlargement: corresponds to the L2 to the S3
segments
4. Fissure and sulci:
⑴ Anterior median fissure: deep wide groove
⑵ Posterior median sulcus: deep slit like groove
⑶ Anterolateral sulcus: anterior (motor) roots emerge serially
⑷ Posterolateral sulcus: posterior (sensory) roots enter spinal
cord, each bear a spinal ganglion which constitutes the first
cell-station of the sensory nerves
- At each intervertebral foramen the anterior and posterior roots
unite to form a spinal nerve
Ⅲ) Relationship of segments of spinal cord to vertebrae
1. A portion of the cord that gives rise to a pair of spinal nerve
constitutes a segment. There are 31 segments in the human spinal
cord: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal.
2. Fetal location－until fetal month, the spinal cord is as long as the
vertebral canal and extends to the leel of the fourth sacral
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vertebra
3. The growth period and “law of descent”－after fourth fetal month, the vertebral
column outgrows the spinal cord. It appears that the cord regresses to the upper lumbar
levels; however, the spinal roots descend through the dural sac to the appropriate
intervetrbral foramina－the law of decent. The result descending distribution of spinal
root forms the cauda equina.
Table 1
Relationship of segments of spinal cord to vertebrae
Spinal segments
Vertebral levels (spines)
Upper cervical region (C1~C4)
Lie opposite the corresponding vertebrae
Lower cervical and upper thoracic
One lower in number than corresponding vertebrae
region (C5~T4)
Middle thoracic region (T5~T8)
Two lower in number than corresponding vertebrae
Lower thoracic region (T9~T12)
Three lower in number than corresponding vertebrae
Lumber segments
T10~T12
Sacral and coccygeal segments
L1
Ⅱ. Internal structures
Ⅰ) Central canal
Ⅱ) Gray matter
1. Posterior horn (column): contains sensory interneurons
⑴marginal layer
⑵Substantia gelatinosa
⑶Nucleus proprius
⑷Nucleus thoracicus: in segments C8~L3
2. Intermediate zone
⑴ Intermediaolateral nucleus (lateral horn or column): lies in segments T1~L3,
containing sympathetic preganglionic neurons
⑵ Sacral parasympathetic nucleus: lies in segments S2~S4, containing
parasympathetic preganglionic neurons
⑶Intermediomedial nucleus: for sensation of viscera
22
3. Anterior horn (column): contain motor neurons
⑴Three kinds of neuron
① α-motor neuron: larger multipolar neuron, innervates extrafusal fibers of
skeletal m., producing contraction of m.
② γ-motor neuron: smaller neuron, innervates intrafusal fibers regulating
muscular tonus
③ Renshaw’s cell: negative feedback mechanism
⑵Two groups of nuclei
①Medial nuclear group: present in most segments of spinal cord, innervating
axial muscles
②Lateral nuclear group: present only in cervical and lumbosacral enlargements,
innervating limb muscles
4. Spinal cord gray matter is arranged in layers: there are ten Rexed’s lamina, the
posterior horn is formed by lamina Ⅰ to Ⅵ, and the intermediate zone corresponding
to lamina Ⅶ, and the anterior horn is composed laminae Ⅷ and Ⅸ, lamina Ⅹ is the
gray matter surrounding the central canal.
Table 2
Important Subdivision of Spinal Cord Gray Matter
Region
Lamina
Nucleus
Posterior horn
Ⅰ
Marginal layer
Ⅱ
Substantia gelatinosa
Ⅲ, Ⅳ
Nucleus proprius
Ⅶ
Nucleus thoracicus (C8~L3)
Ⅶ
Intermediolateral nucleus (T1~L3)
Ⅶ
Sacral parasympathetic nucleus (S2~S4)
Ⅶ
Intermediomedial nucleus
Ⅸ
Motor neuron
Intermediate zone
Anterior horn
23
Ⅲ) White matter
1. White matter is arranged in three
funiculi, ie,
⑴ Anterior funiculus: between anterior
median fissure and anterolateral
sulcus
⑵Lateral funiculus: between anterolateral and posterolateral sulcuses
⑶Posterior funiculus: between posterolateral and posterior median sulcuses
⑷ Anterior white commissure: anterior to the central canal, composed of crossing
fibers
2. White matter contains three kinds of fibers: ascending, descending, and fasciculus
proprius
Table 3
Ascending tracts
Tract
Site of origin
Funiculus
Termination
Function
Fasciculus
Spinal ganglia
Posterior
Gracile nucleus
Convey proprioceptive
gracilis
Fasciculus
cuneatus
below
and fine touch
segment T5
sensation of trunk
Spinal ganglia
Cuneate nucleus
and limbs
above segment
T4
Posterior
Homolateral
Lateral
Cerebellum
spinocerebellar
nucleus
proprioception from
thoracicus
lower limb and lower
Anterior
Contralateral
portion of trunk
spinocerebellar
Laminae
Ⅴ~Ⅶ
24
Unconscious
Laminae Ⅰ,
Spinothalamic
Ⅳ~Ⅶ
Lateral
Dorsal thalamus
Pain, temperature and
and
simple touch
anterior
sensation of trunk
and limbs
Table 4
Descending tracts
Tract
Site of origin
Funiculus
Termination
Function
Lateral
Cerebral cortex
Lateral
Laminae
Voluntary movement
Ⅳ~Ⅸ
corticospinal
Anterior
Cerebral cortex
Anterior
anterior horn
Red nucleus
Lateral
Laminae
corticospinal
Rubrospinal
Excitatory of flexors
Ⅶ~Ⅶ
Vestibulospinal
Homolateral
Anterior
Laminae
Excitatory of extensors
Ⅶ~Ⅷ
vestibular
nuclei
Reticulospinal
Reticular
formation
Medial
longitudinal
Vestibular
Anterior
Laminae
Voluntary movement
Ⅶ~Ⅷ
and lateral
Anterior
Laminae
Ⅶ~Ⅷ
nuclei
Coordinate neck with eye
movment
fasciculus
Tectospinal
Superior
Anterior
Laminae
Ⅵ~Ⅷ
colliculus
Fasciculus
Spinal cord
proprius
Anterior,
Spinal cord
lateral and
Intrinsic reflex mechanism
of spinal cord
posterior
Ⅲ. Main functions of spinal cord
1. Conduction of excitations
2. Reflex activity
Ⅳ. The clinical consideration
Complete hemisection of spinal cord － Brown-Sequard Syndrome
Ipsilateral loss of vibration and proprioception and fine touch sensation, weakness; increased
25
tone and reflexes; contralateral loss of pain and temperature
Sdudy questions
Ⅰ. Single choice questions (there five choices on each question, only one is correct, please
circle the correct answer):
1. In adult, the lower end of spinal cord is at the level of
A. inferior border of L1
B. superior border of L1
C. inferior border of L2
D. superior border of L2
E. L3
2. The position of the 10th thoracic segment of spinal cord is at the level of
A. 9th thoracic vertebra
B. 8th thoracic vertebra
C. 7th thoracic vertebra
D. 6th thoracic vertebra
E. 1st lumbar vertebra
Ⅱ. Multiple choice questions (two to five choices are correct, please circle the correct answers):
1. The spinal cord
A. lies in vertebral canal
B. continuous with pons at level of foramen magnum
C. has cervical and lumbosacral enlargement
D. can be divided into 33 segments
E. connected with sympathetic trunks directly
2. The fasciculi ( or tracts ) which lie in the lateral funiculus of the spinal cord are
A.
the fasciculus cuneatus
B.
the anterior corticospinal tract
C.
the lateral corticospinal tract
D.
the rubrospinal tract
E.
the fasciculus gracilis
Ⅲ. Answer the following questions
1. Write out the position and external features of the spinal cord.
2. Write out the tne names of ascengding and descending tracts in the spinal cord.
3. Describe the divisions of the gray and white matters.
26
The brain stem
Learning Objectives
You should:

掌握脑干的组成和外形（包括菱形窝）
。

掌握第四脑室的位置及连通关系。

掌握脑干内神经核的分类。掌握脑神经核的机能分类、各类脑神经核的名称、位置及
其与脑神经的关系和功能。

掌握薄束核、楔束核、脑桥核、红核、黑质、顶盖前区、上丘灰质层、下丘核的位置。
了解其它非脑神经核的位置。

掌握脑干内锥体束、内侧丘系、脊髓丘系、三叉丘系、外侧丘系的位置与功能。

了解延髓锥体交叉、内侧丘系交叉、橄榄中部、脑桥下份、脑桥中份、中脑下丘、中
脑上丘水平切面的主要结构。

了解脑干网状结构的位置及功能。了解脑干各部损伤后的临床表现。
The brain stem consists of medulla oblongata, pons and midbrain.
27
Ⅰ. External features
A. Medulla oblongata
1. Ventral surface
a) Pyramid: contain pyramidal tract (corticospinal tract)
b) Decussation of pyramid: formed by crossing fibers of corticospinal tract
c) Olive: produced by underlying inferior olivary nucleus
d) Anterolateral sulcus: rootlets of hypoglossal nerve emerge from it
e) Retroolivary sulcus: rootlets of glossopharyngeal, vagus and accessory nerves emerge
from it
2. Dorsal surface
a) Lower portion
⑴Gracile tubercle: produced by underlying gracile nucleus
⑵Cuneate tubercle: marks the site of cuneate nucleus
⑶ Inferior cerebellar peduncle: formed by fibers which connect spinal cord and
medulla with cerebellum
⑷Obex: the apex of v-shaped caudal fourth ventricle
b) Upper portion: forms the lower half of rhomboid fossa
B. Pons
1. Ventral surface
a) Basilar part: convex
b) Basilar sulcus: a groove along the midline, lodges the basilar artery
c)
Bulbopontine sulcus: from medial to lateral, the abducent, facial and
vestibulocochlear nerves appear
d) Middle cerebellar peduncle: a broad transverse band of nerve fibers which enter
the corresponding cerebellar hemisphere
e) Trigeminal nerve: emerges from the junction of basilar part and middle cerebellar
peduncles
f) Pontocerebellar trigone: the junction of medulla, pons and cerebellum
28
2. Dorsal surface — forms upper part of rhomboid fossa
a) Superior cerebellar peduncle
b) Superior medullary velum
c) Trochlear nerve: lies above superior medullary velum
C. Midbrain
1. Ventral surface
a) Crus cerebri: formed by descending fibers
b) Interpeduncular fossa: a deep depression, oculomotor nerves emerge from medial
of crus cerebri
c) Posterior perforated substance: the floor of interpeduncular fossa, through which
pass central branches of posterior cerebral artery
2. Dorsal surface
a) Superior colliculus: constitute centers for visual reflexes
b) Inferior colliculus: associated with auditory pathway
c) Brachium of superior and inferior colliculi: interconnect the superior and inferior
colliculi to lateral and medial geniculat bodies respectively
D. Fourth ventricle
1. Position: situated ventral to cerebellum, and dorsal to pons and cranial half of medulla
2. Floor-- rhomboid fossa
a) Boundaries
(1) Inferolateral: gracile and cuneate tubercles, inferior cerebellar peduncle
(2) Superolateral: superior cerebellar peduncle
(3) Lateral recess
b) Features
(1) Median sulcus
(2) Sulcus limitans
(3) Vestibular area: a triangular area lateral to sulcus limitans, overlies vestibular
nuclei
(4) Acoustic tubercle: lies on lateral angle of vestibular area, overlying dorsal
cochlear nucleus
(5) Medial eminence: a longitudinal elevation between median sulcus and sulcus
limitans
(6) Striae medullares
(7) Facial colliculus: elongated swelling, which overlies nucleus of abducent n.
29
and genu of facial nerve
(8) Hypoglossal triangle: on medial eminence, below striae medullares, verlying
hypoglossal nucleus
(9) Vagal triangle: overlies dorsal nucleus of vagus nerve
(10) Funiculus separans
(11) Area postrema
(12) Locus ceruleus
2. Roof: V- shaped as seen in sagittal
a) Anterior part: formed by superior cerebellar peduncle and
superior medullary velum
b) Posterior part: formed by inferior medullary velum and choroid
plexus of fourth ventricle
c) Three apertures
(1) Median aperture of fourth ventricle
(2) Two lateral apertures of fourth ventricle
Ⅱ. Internal structures
A. Gray matter
1. Cranial nerve nuclei
Table 1
Somatic motor nuclei
Nucleus
Site
Nucleus of oculomotor n.
Midbrain
Cranial n.
Ⅲ
Function
Supreior, inferior,and medial recti,
inf. obliquus, levator
palpebrae superioris
Nucleus of trochlear n.
Midbrain
Ⅳ
Superior obliquus
Nucleus of abducent n.
Pons
Ⅵ
Lateral rectus
Nucleus of hypoglossal n.
Medulla
Ⅻ
Muscles of tongue
30
Table 2
Special visceral motor nuclei
Nucleus
Site
Cranial n.
Function
Motor nucleus of
Pons
Ⅴ
Masticatory muscles
Pons
Ⅶ
Facial m., platysma, posterior
trigeminal n.
Nucleus of facial n.
belly of digastric, stylohyoid,
stapedius
Medulla
Nucleus ambiguus
Ⅸ,Ⅹ.Ⅺ
Skeletal m. of pharynx, larynx
and upper part of esophagus
Medulla-cervical
Accessory nucleus
Ⅺ
Sternocleidomastoid, trapezius
cord
Table 3
General visceral motor nuclei
Nucleus
Site
Cranial n.
Function
Accessory oculomotor
Midbrain
Ⅲ
Sphincter pupillae and ciliary m.
Pons
Ⅶ
Submandibular, sublingual and
nucleus
Superior salivatory nucleus
lacrimal glands
Inferior salivertory nucleus
Medulla
Ⅸ
Parotid gland
Dorsal nucleus of vagus n.
medulla
Ⅹ
Many cervical, thoracic and
abdominal viscera
Table 4
Visceral afferent nuclei ( general and special )
31
Nucleus
Site
Cranial n.
Function
Nucleus of solitary tract
Medulla
Ⅶ,Ⅸ,Ⅹ
Taste and visceral sensation
Table 5
General somatic afferent nuclei
Nucleus
Site
Cranial n.
Function
Mesencephalic nucleus of
Midbrain
Ⅴ
Proprioception of head
Pontine nucleus of trigeminal n.
Pons
Ⅴ
Tactile sensation of head
Spinal nucleus of trigeminal n.
Medulla
Ⅴ
Pain and temperature sense
trigeminal n.
of head
Table 6
Special somatic afferent nuclei
Nucleus
Site
Cranial n.
Function
Cochlear nuclei
Pons and medulla
Ⅷ
Sense of hearing
Vestibular nuclei
Pons and medulla
Ⅷ
Sense of equilibrium
2. Non-cranial nerve nuclei
Nucleus
Site
Gracile nucleus
Medulla (underneath gracile tubercle)
Cuneate nucleus
Medulla (underneath cuneate tubercle)
Superior olivery nucleus
Pons
Pontine nucleus
pons
Nucleus of inferior colliculus
Midbrain
Gray matter layers of superior colliculus
Midbrain
Red nucleus
Midbrain
Substantia nigra
Midbrain
Pretectal area
Midbrain
B. White matter
1. Ascending tracts
a) Medial lemniscus
The fibers in fasciculus gracilis and cuneatus end in the gracile and cuneate nuclei. The axons
from latter cells pass ventromedially and cross the midline forming the decussation of the medial
lemniscus. After crossing the midline, fibers turn upwards between midline and inferior olivary
32
nuculeus, behind pyramidal tract, and run cranially through the trapezoid body in the anterior
margin of the tegmentum of pons, thereafter, they turn upwards and ascend lateral to the red
nucleus in tegmentum of midbrain, to reach the ventral posterolateral nucleus (VPL) of dorsal
thalamus.
b) Spinal lemniscus
In the medulla oblongata the lateral and anterior spinothalamic tracts become blended to form
spinal lemniscus which passes upward at dorsolateral of inferior olivary nuculeus, through pons
and midbrain, lateral to medial lemniscus, to reach the ventral posterolateral nucleus (VPL) of
dorsal thalamus.
c) Trigeminal lemniscus
The spinal nucleus and pontine nucleus of trigeminal nerve give rise the axons to the opposite
side to join the trigeminal lemniscus running through the pons and midbrain to the ventral
poseromedial nucleus (VPM) of dorsal thalamus.
d) Lateral lemniscus
Fibers from cochlear nuclei run transversely across midline to the opposite side and turn
upward to form the lateral lemniscus . The transversely running fibers form the trapezoid body
which occupy the ventral potion of the tegmentum of pons where they mingle with the fibers of
medial lemniscus, crossing them at right angle. They then pass through lateral to the medial
lemniscus in the midbrain, to reach the inferior collicul
2. Descending tracts
a) Corticospinal tract
This is a long pathway originating in the cerebral cortex. It descends through the middle 3/5 of
crus cerebri. In the pons where they are separated into several small bundles by transversely
disposed ponticerebellar fibers. Blower pons the fibers are closely grouped together in the
pyramids on the ventral aspect of medulla oblongata. In the lower half of medulla, the majority
of corticospinal fibers cross to the opposite side of the brain stem, forming the decussation of
pyramid. These decussating fibers turn downward to descend in the lateral funiculus of spinal
cord as the lateral corticospinal tract. The uncrossed fibers retain their ventromedial position and
descend in the anterior funiculus of spinal cord as the anterior corticospinal tracts.
b) Others: rubrospinal tract, tectospinal tract, vestibulospinal tract, and reticulospinal
tract
C. Reticular formation of brain stem
1. Ascending reticular activating system (ARAS)
33
2. Motor central and vital centres
a) Reticulospinal tract
b) Cardiovascular center and respiratory center
3. Serotonergic rapheal nuclei
D. Central canal
Centra canal → fourth ventricle → mesencephalic aqueduct
Ⅲ. The characters of internal structure of brain stem
A. Medulla oblongata
1. Upper part (open part)
a) Appearance of inferior olivary nuculeus and inferior cerebellar peduncle
b) Enlargement of central canal to form the fourth ventricle floor
2. Lower part (closed part) : two decussations--decussations of medial lemniscus and
pyramid
Decussations
of pyramid
Decussations of
medial lemniscus
Inferior olivary
nuculeus
B. Pons
1. Tegmentum of pons: directed upward continuation of
medulla oblongata, excluding the pyramids. The central
gray matter is spread out to form the floor of the upper
part of the fourth ventricle , a number of new cranial nerve
nuclei are present.
2. Basilar part: contain both longitudinal and transverse fibers intermixed with pontine
nuclei
C. Midbrain
1. Rectum of midbrain: includes superior and inferior colliculi
2. Cerebral peduncle
a) Tegmentum: contain ascending tracts, central gray matter, recticular formation and so
34
on
b) Substentia nigra
c) Crus cerebri: the pyramidal tract occupy the middle three-fifths of the crus, the
frontopontine tract occupy the medial one-fifth and tempo-occipito-pontine tract the
lateral one-fifth of the crus
Sdudy questions
Ⅰ. Single choice questions (there five choices on each question, only one is correct, please
circle the correct answer):
1．The cranial nerves nuclei in the medulla oblongata don’t include
A. nucleus of hypoglassal nerve
B. nucleus ambiguus
C. abducens nucleus
D. spinal nucleus of trigeminal nerve
E. nucleus of solitary tract
2．The decussation of medial lemniscus
A. represents the crossing of motor tract
B. lies below the decussation of pyramid
C. lies at the level of the facial colliculus
D. formed by the crossing fibers of spinal lemniscus
E. formed by the crossing fibers which arise from the gracile and cuneate nuclei
Ⅱ. Multiple choice questions (two to five choices are correct, please circle the correct answers):
1．The nuclei in the midbrain are
A. accessory nucleus of oculomotor nerve
B. nucleus of trochlear nerve
C. pontine nucleus of trigeminal nerve
D. mesencephalic nucleus of trigeminal nerve
35
E. gracile nucleus
2．The nuclei related to the vagus nerve
A. dorsal nucleus of vagus nerve
B. inferior salivatory nucleus
C. nucleus ambiguus
D. nucleus of solitary tract
E. nucleus of hypoglossal nerve
Ⅲ. Answer the following questions
1．Write out the names of the somatic motor nuclei of the brain stem and the meatus or
foramina from which their fibers leave the skull.
2．Write out the names of the somatic motor nuclei of the brain stem and the meatus or
foramina from which their fibers leave the skull.
3．Write out the names and functions of lemnisci of the brain stem.
The Cerebellum
Learning Objectives
You should:

掌握小脑的位置、外形、分叶和机能分区。

了解小脑核的名称、位置。

了解小脑的纤维联系与功能。
Ⅰ. Position, external features and lobs
A. Potion: lies above and behind the medullar and pons and occupies posterior cranial fossa
B. External features
36
1. Consists of two cerebellar hemisphere united in the midline by the vermis
2. Three peduncles connect each hemisphere to the three parts of brainstem
a) Inferior cerebellar peduncle connect with medulla and with spinal cord, contain
both afferent and efferent fibers
b) Middle cerebellar peduncle connect with pons, contain afferent fibers
c)
Superior cerebellar peduncle connect with midbrain, contain mostly efferent
fibers
3. Tonsil of cerebellum: two elevated masses on inferior surface of hemispheral portion just
nearby foramen magnum
C. Lobs
1. Two deep fissures
a) Primary fissure
b) Posterolateral fissure
2. Three lobs
a) Flocculonodular lobe: flocculus and nodule
b) Anterior lobe
corpus of cerebellar
c) Posterior lobe
Ⅱ. Internal structures
A. Gray matter
1. Cerebellar cortex
2. Cerebellar nuclei
a) Dentate nucleus
b) Fastigial nucleus
37
c) Interposed nucleus
⑴ Emboliform nucleus
⑵ Globose nucleus
B. White matter--medullary center
Ⅲ. Connections and function of cerebellum
Three functional divisions

Vestibulocerebellum ( archicerebellum ): Flocculonodular lobe

Spinocerebellum ( paleocerebellum ): vermis and intermediate zone

Cerebrocerebellum (neocerebellum ): lateral zone
A. Vestibulocerebellum
1. Connections
a) Afferents: receive input from vestibular nuclei and primary vestibular
b) Efferents: projects to the vestibular nucleus → vestibulospinal tract and medial
longitudinal fasciculus → motor neurons of anterior horn
2. Function: involved in eye movements and maintain balance
B. Spinocerebellum
1. Connnection
a) Afferents: receive somatic sensory information via spinocerebellar tracts
b) Efferents:
(1) Vermis projects to the fastigial nucleus → vestibular nuclei and reticular
formation → vestibulospinal tract and reticulospinal tract → motor neurons of
anterior horn
(2) Intermediate zone projects to the interposed nuclei →
①contralateral red nucleus → rubrospinal tract →motor neurons of anterior horn
② contralateral VI →cerebral cortex→ coticospinal tract→motor neurons of
anterior horn
2. Function: play an important role in control of muscle tone and coordination of muscle
movement on the same side of the body
C. Cerebrocerebellum
1. Connection
a) Afferents: receives input from the cerebral cortex via a relay in pontine nuclei
b)
Efferents: projects to dentate nucleus → VI → primary motor cortex →
corticospinal tract → motor neurons of anterior horn
3. Function: participates in planning movements
38
Sdudy questions
Ⅰ. Single choice questions (there five choices on each question, only one is correct, please
circle the correct answer):
1. The tonsil of cerebellum
A. are two elevated masses of the anterior lobe
B. is a part of the archiocerebellum
C. is a part of the neocerebellum
D. its fibers project to the red nucleus
E. lies below the foramen magnum
2. Which is wrong about cerebellum
A. it lies in posterior cranial fossa
B. the anterior lobe is called cerebellar hemisphere
C. cerebellum has two cerebellar hemisphere
D. there are three pairs cerebellar peduncles
E. the dentate nucleus is the largest cerebellar nuclei
Ⅱ. Multiple choice questions (two to five choices are correct, please circle the correct answers):
1. Which statements are correct about cerebellum
A. The cerebellum is located in the posterior cranial fossa
B. The cerebellum is divide into flocculonodular, ant. and pos. lobe
C. The dentate nucleus is the largest nucleus of the cerebellar nuclei
D. There are three pairs of cerebellar peduncles
E. The sup. cerebellar peduncle consists mainly of the efferent fibers
Ⅲ. Answer the following questions
1. Write out the positionand external features of the cerebellum.
2. Write out the names of cerebellar nuclei.
39
The Diencephalon
Learning Objectives
You should:

掌握间脑的位置、分部及各部的组成和位置。

掌握第三脑室的位置与连通。

了解背侧丘脑核团的划分。掌握特异性中继核团的名称、纤维联系和功能（包括后丘
脑）
。

掌握下丘脑的主要核团及其与垂体的关系。了解下丘脑的功能。
Ⅰ. Position and subdivision
A. Position: Lies between midbrian and cerebrum, almost entirely surrounded by cerebral
hemisphere
40
B. Subdivision
1. Doral thalamus
2.
Epithalamus:
includes
thalamic
medullary
stria,
habenular trigone , habenular commissure, pineal body
and posterior commissure
3. Hypothalamus
4. Metathalamus
5. Subthalamus: transition zone between diencephalons and tegmentum of midbrain,
contain subthalamic nucleus, parts of red nucleus and substantia nigra
Ⅱ. Dorsal thalamus
A. External features
1. A large egg-shaped nucleus mass, it’s anterior end
called anterior thalamic tubercle, the posterior end
called pulvinar
2. Right and left portion of thalamus are joined by interthalamic adhesion
B. Classification of nuclei of dorsal thalamus
The thalamus has anterior, medial and lateral divisions defined by internal medullary lamina
Topographical Subdivisions of the Thalamus and Their Principal Nuclei
Subdivision
Principal Nuclei
Common abbreviation
Ant. nuclear group
Med. nuclear group
Lat. nuclear group
Dorsal tier
Lateral dorsal
LD
Lateral posterior
LP
Pulvinar
Ventral tier
Ventral anterior
VA
Ventral intermediate
VL
Ventral posterior
VP
Ventral posterolateral
VPL
Ventral posteromedial
VPM
41
C. Functional subdivision
1. Nonspecific relay nuclei:,
a) Midline nucleus group
b) Intralaminar nuclear group
c) Thalamic reticular nucleus
receive afferents from rhinencephalon and reticular formation of brain stem, project mainly
to hypothalamus and corpus striatum
2. Association nuclei
a) Anterior nuclear group
b) Medial nuclear group
c) Dorsal tier of lateral nuclear group
Receive input from many converging sours and in turn project widely to the association areas
of cerebral cortex
3. Special relay nuclei
a) Vent. anterior nucleus
receiving dentate nucleus, globus
pallidus and substantia nigra to
b) Vent. intermediate nucleus
motor cortex
c) Vent. posteromedial nucleus: receives trigeminal lemniscus and teste fibers
d) Vent. posterolateral nucleus: receives medial lemniscus and spinal lemniscus
projects to primary somatosensory area via central thalamic radiation
Ⅲ. Metathalamus
A. Medial geniculate body (MGN)
1. Relay station of audition
2. Receive fibers from inferior colliculus
3. Projects to auditory area via acoustic radiation
B. Lateral geniculate body (LGN)
1. Relay station of vision
2. Receive fibers from optic tract
3. Projects to visual area via optic radiation
Ⅳ. Hypothalamus: lies ventral to thalamus
A. Boundaries
1. Superiorly: hypothalamic sulcus
42
2. Inferiorly: optic chiasma, tuber cinereum, infundibulum and mamillary body
3. Anterior: lamina terminalis
4. Posterior: continues with midbrain tegmentum
B. Subdivisions and important nuclei
1. Preoptic region
2 . Supraoptic region
a)
Supraoptic nucleus: produce antidiuretic
hormone (ADH, or vasopression)
b) Paraventricular nucleus: produce oxytocin
3. Tuberal region
a) Infundibular nucleus
b) Ventromedial nucleus
c) Dorsomedial nucleus
4. Mamillary region
a) Mamillary nucleus
b) Posterior hypothalamic nucleus
C. Connection
1. Connects with limbic system
a) Septal area→terminal stria (ST) and ventral amygdaloid pathway (VAP) →
amagdaloid body
b) Hippocampus → fonix (F) → mamillary body
c) Septal area → medial forebrain bundle (MFB)→ midbrain tegmentum
2. Connects with brainstem and spinal cord
a) Septal area → medial forebrain bundle(MFB) → midbrain tegmentum
b) Periventricular gray matter → dorsal longitudinal fasciculus (DLF) → central gray
matter and midbrain tegmentum
3. Connects with dorsal thalamus
Mamillary body→mamillothalamic tract (MTT) → anterior nuclear group of thalamus
4. Connects with hypophysis
a) Supraoptic nucleus (vasopressin) →supraopticohypophyseal tract →posterior lobe of
hypophysis
b) Paraventicular nucleus (oxytocin) →paraventriculohypophyseal tract→posterior lobe
of hypophysis
43
c) Parvicellular neurons in the arcuate nucleus and nearby region of the walls of the
third ventricle secrete releasing and inhibiting hormones → tuberoinfundibular tract
→portal vein of hypophsis → anterior lobe of hypophsis
D. Function: regulates functions of neuroendocrine system and autonomic nervous system
Ⅴ. Third ventricle
A. Position: a narrow ventricle cleft lies within diencephalons
B. Boundaries
1. Roof: choroids plexus
2. Floor: optic chiasma, tuber cinereum, infundibulum and mamillary body
3. Anterior: lamina terminalis
4. Posterior: continuous with mesencephalic aqueduct
5. Lateral wall: dorsal thalamus and hypothalamus
C. Communication
Third ventricle →mesencephalic aqueduct → fourth ventricle
Sdudy questions
Ⅰ. Single choice questions (there five choices on each question, only one is correct, please
circle the correct answer):
1. The ventral posterolateral nucleus of thalamus receivess fibers from
A. spinal lemniscus
B. lateral lemniscus
C. medial lemniscus
D. hypothalamus
E. trigeminal lemniscus
2. The structures belonging to the hypothalamus include
A. optic chiasma
B. mamillary body
C. paraventricular nucleus
D. ventral posterior nucleus
E. medial geniculate body
Ⅱ. Multiple choice questions (two to five choices are correct, please circle the correct answers):
1. The diencephalon consists of
44
A. epithalamus
B. hypothalamus
C. subthalamus
D. dorsal thalamus
E. metathalamus
2. The specific relay nuclei in the diencephalon are
A.
the ventral anterior nucleus of thalamus
B.
the ventral posterolateral nucleus of thalamus
C.
the lateral geniculate body
D.
the anterior nuclear group of thalamus
E.
the supraoptic nucleus
Ⅲ. Answer the following questions
1. Write out the divisions of the diencephalons.
2. Write out the names of specific nuclei of diencephalon and which fibres they receive.
The Telencephalon
Learning Objectives
You should:

掌握大脑半球的主要沟裂、分叶和各叶的主要沟回。

掌握第 I 躯体运动区、第 I 躯体感觉区、视区、听区的位置及功能定位。掌握语言中
枢的位置。

掌握基底核的组成和位置。

掌握侧脑室的形态分部和各部的位置。

了解大脑半球白质纤维的分类。

掌握内囊的位置、分部及各部所通过的主要纤维束。了解内囊损伤后的临床表现。

了解嗅脑和边缘系统的组成及功能。
Ⅰ. External feature
45
The telencephalon consists of right and left cerebral hemisphere, partially separated by a deep
sagittal grove, cerebral longitudinal fissure. At the button of this fissure, the hemispheres are
connected with each other by the great central white commissure, the corpus callosum. The
cerebral transverse fissure intervenes between the hemispheres and the cerebellum.
Each hemisphere has three surfaces: superolateral, medial and inferior. About 4 cm in front of
the occipital pole on the inferior border there is an indentation—the preoccipital notch.
The surface of the cerebral cotex is folded into gyri (ridges) separated by sulci (groove). Gyri
increase the surface area, thereby accommodating more functional columns. Although the
pattern of gyri and sulci is variable, the location of some ridges and grooves is remarkably
consistent, providing convenient landmarks.
Central sulcus
A. Three sulci
Lateral sulcus
Parietooccipital sulcus
Frontal lobe
Parietal lobe
B. Five lobes
Temporal lobe
Occipital lobe
Insular lobe
Ⅱ. Sulci and gyri
A. Superolateral surface
1.
Frontal lobe: precentral sulcus, superior frontal sulcus, inferior frontal sulcus,
precentral gyrus, superior frontal gyrus, middle frontal gyrus and inferior frontal
gyrus
2.
Parietal lobe: postcentral sulcus, postcentral gyrus, intraparietal sulcus, superior
parietal lobule, inferior parietal lobule, supramarginal gyrus, angular gyrus
3. Temporal lobe: superior temporal sulcus, inferior temporal sulcus, superior temporal
gyrus, middle temporal gyrus, inferior temporal gyrus and transverse temporal gyri
46
B. Medial surface
corpus callosum, callosal sulcus, cingulate gyrus, cingulate sulcus, marginal ramus,
paracentral lobule, calcarine sulcus , cuneus, lingual gyrus
C. Inferior surface
olfactory bulb, olfactory tract, olfactory trigone, anterior perforated substance, collateral
sulcus, occipitotemporal sulcus, medial occipitotemporal gyrus, lateral occipitotemporal
gyrus,
hippocampal sulcus, parahippocampal gyrus, uncus, hippocampus, dentate gyrus,
hippocampal formation
D. Functional location of the cerebral cortex
archicortex (hippocampal formation)
Cerebral cortex
paleocortex (rhinencephalon )
3 cell layers
neocortex (most of cerebral cortex)
6 cell layers
1. Primary motor area
a) Located in precentral gyrus and anterior
portion of paracentral lobule
b) Characters
(1) Representation is inverted, but head
and
face are upright
(2) A body part is represented by a
cortical area proportional to its use
rather than its size
c) Receiving fibers from postcentral gyrus, VA, VL and VPL, sending out fibers to form
pyramidal tract, controlling voluntary movements
2. Primary somatosensory area
a) Lies in postcentral gyrus and posterior portion of
paracentral lobule
b) Sensory representation, like motor area, is crossed and
inverted
c) Receiving and interpret sensation from opposite side of
body
3. Visual area
a) Lie on either side of calcarine sulcus in medial surface of occipital lobe
47
b) Visual cortex of one hemisphere receives impression from temporal part of retina of
same side and nasal part of opposite side
c) Lesions of visual cortex produce contralateral homonymous visual field defections
4. Auditory area
a) Located in transverse gyri
b) Receive auditory information from both ears
5. Vestibular area: located in front of superior temporal gyrus
6. Olfactory area: located near the uncus
7. Taste area: located at frontal operculum
8. Language area: it is dominant in left
hemisphere in right-handed person
a) Motor speech area
(1) Located in posterior portion of
inferior frontal gyrus
b
b
a
A
(2) damage: motor aphasia
a
b) Writing area
(1) Located in posterior portion of middle frontal gyrus
(2) Damage: agraphia
c) Auditory speech area
(1) Located in posterior portion of superior temporal gyrus
(2) Lesion: sensory aphasia
d) Visual speech area
(1) Located in angular gyrus
(2) Lesion: alexia
Ⅲ. Internal structures
A. Lateral ventricle: C-shaped
1. Position: located in cerebral hemispheres
2. Four parts
a) Central part: lies in parietal lobe
b) Anterior horn: extends into frontal lobe
c) Posterior horn extend into occipital lobe
d) Inferior horn: extend into temporal lobe
48
c
c
d
3. Communication
lateral ventricle → interventricular foramen → third ventricle
C. Basal nuclei: deep within base of cerebral hemisphere
globus pallidus: paleostriatum
lentiform nucleus
putamen
1. Corpus striatum
neostriatum
caudate nucleus
2. Claustrum
3. Amygdaloid body
Ⅳ. White matter: cerebral medullary
A. Association fibers: run between gyri within the same hemisphere
1. Cerebral arcuate fibers
2. Superior and inferior longitudinal fasciculi
3. Uncinate fasciculus
4. Cingulum
B. Commissural fibers: run between left and right hemisphere
1. Corpus callosum: rostrum, genu, trunk, splenium
2. Anterior commissure
3. Fornix and commissure of fornix
C. Projection fibers: connect cortex with lower part of brain and spinal cord
include both ascending and descending fibers
★ Internal capsule
1. Position: a thick lamina of white matter lying between caudate
nucleus, thalamus and lentiform nucleus
2. Three parts
a) Anterior limb of internal capsule
(1) Lies between caudate nucleus and lentiform nucleus
(2) Containing frontopontine tract and anterior thalamic
radiation
b) Genu of internal capsule
49
and they
(1) Is angle at which anterior and posterior limbs meet
(2) Containing corticonuclear tract
c) Posterior limb of internal capsule
(1) Lies between thalamus and lentiform nucleus
(2) Contain corticospinal tract, corticorubral tract, central thalamic radiation,
parieto-occipito-temporo-pontine tract, acoustic radiation and optic radiation
Ⅴ. Limbic system
A. Composition
1. Limbic lobe: includes septal area, cingulated gyrus,
parahippocampal gyrus, hippocampus, dentate
gyrus, temporal pole, anterior part of insular lobe
and so on
2. Associated subcortical nuclei: amygdaloid body, septal nuclei, hypothalamus,
epithalamus, anterior nucleus group of thalamus, tegmentum of midbrain
B. Function: concerned with visceral activities, olfaction, emotion and memory, so this
system is called ‘visceral brain’
Sdudy questions
Ⅰ. Single choice questions (there five choices on each question, only one is correct, please
circle the correct answer):
1．The visual speech area is located in
A. posterior portion of superior frontal gyrus
B. posterior portion of middle frontal gyrus
C. posterior portion of inferior frontal gyrus
D. calcarine sulcus
E. angular gyrus
2. The left side of inferior 1/3 of postcentral gyrus receives the fibers from
A. left spinal lemniscus
B. right spinal lemniscus
C. left trigeminal lemniscus
D. right trigeminal lemniscus
E. leftt ventral posteromedial nucleus
Ⅱ. Multiple choice questions (two to five choices are correct, please circle the correct answers):
50
1. The basa nuclei of cerebrum include
A. claustrum
B. substantia nigra
C. amygdaloid body
D. lentiform nucleus
E. caudate nucleus
2. The commissural fibers between left and right cerebral hemisphere
A. cingulum
B. corpus callosum
C. anterior commissure
D. cerebral arcuate fibers
E. commissure of fornix
Ⅲ. Answer the following questions
1. Describe the positions and functional localization of the primary motor area , primary
somatosensory area, visual area, auditory area, language area of the cerebral cortex.
2. Write out the organization andposition of the basal ganglia.
3. Write out the position, divisions of the internal capsule and the name of main nerve fibrous
tracts in it.
The Nervous pathway
Learning Objectives
You should:

感觉传导通路

掌握躯干、四肢意识性本体觉和精细触觉传导通路的组成，各级神经元胞体所在
部位，纤维束在中枢各部的位置及向大脑皮质投射的部位。

了解躯干、四肢非意识性本体感觉传导通路。

掌握躯干、四肢及头面部痛温觉和粗触压觉传导通路的组成，各级神经元胞体所
在的部位，纤维束在中枢各部的位置及向大脑皮质投射的部位。

掌握视觉传导通路的组成，各级神经元胞体所在部位，纤维部分交叉（视交叉）
的情况，在内囊的位置和向大脑皮质投射的部位。了解视觉传导通路不同部位损
伤后的视野变化。掌握瞳孔对光反射的通路。了解该通路不同部位损伤后瞳孔对
光反射的变化。
51


了解听觉传导通路的组成。
运动传导通路

掌握上、下运动神经元的位置。

掌握皮质脊髓束在中枢各部的位置、纤维交叉部位及其与下运动神经元联系的状
况。

掌握皮质核束在中枢各部的位置及其对脑神经运动核的管理。

了解上、下运动神经元损伤后的临床表现。

掌握锥体外系的概念。了解主要的锥体外系通路。
Receptor → afferent neuron → central nervous system → efferent neuron →effector
Sensory pathways
Motor pathways
Ⅰ. Sensory pathways
A. Proprioceptive pathways
1. Conscious proprioceptive and fine touch pathway of trunk and limbs
It is a three-neuron chain that transmits fine touch, vibratory and transmits proprioceptive
information from the trunk and limbs to the cerebral cortex.
a) The 1°( first-order ) neurons: pseudounipolar neurons, located in
spinal ganglion, the peripheral branches run through the corresponding spinal
nerve to the sensory receptors in skin, muscles, joints or tendons, the central
branches enter spinal cord by way of dorsal roots and join the posterior
funiculus on the same side. Thus fibers entering below the midthoracic level
spinal cord form medially-placed fasciculus gracilis which extends whole
length of cord, while whose entering above this level form the fasciculus
cuneatus which is confined to upper part of cord. The fibers of both fasciculi
continue upwards into brain stem and terminate about the middle of medulla
by synapsing with the cells of gracile or cuneate nuclei.
b) The 2°(second-order ) neurons: located in gracile and cuneate nuclei, the axons of
52
the 2°neurons pass ventromedially and cross the midline forming the decussation of medial
lemniscus. After crossing the midline, fibers turn upwards on the opposite side as the medial
lemniscus between midline and inferior olivary nucleus, behind pyramidal tract, and run
cranially through the trapezoid body in the anterior margin of the tegmentum of pons, thereafter,
they turn upwards and ascend lateral to the red nucleus in tegmentum of midbrain, to reach the
dorsal thalamus, where they synapse with the 3°neurons in ventral posterolateral nucleus (VPL)
of dorsal thalamus
c) The 3°(third –order) neurons: VPL nucleus of dorsal thalamus send their axons by way
of the central thalamic radiations through posterior limb of internal capsule to cortex of superior
and middle parts of postcentral gyrus and to posterior part of paracentral lobule, some fibers
project to precentral gyrus
Muscles
1°neuron
tendons
joints
central branches enter posterior funiculus of spinal cord
spinal ganglion
skin
f. entering below T5 level of cord form fasciculus gracilis
f. entering above T4 level of cord form fasciculus cuneatus
2°neuron
╳
decussation of medial lemniscus
〈○
ascending as medial lemniscus
gracile and cuneate nuclei
3°neurons central thalamic radiation
gyrus, posterior part of paracentral lobule
〈○
VPL
superior and middle part of postcentral
via post. limb of internal capsule
and precentral gyrus
2. Unconscious proprioceptive pathway
Muscles
thoracic nucleus
〈○
joins
tendons
posterior spinocerebellar tract
spinal ganglion
lamina Ⅴ-Ⅶ
anterior spinocerebellar tract
53
(lumbosacral enlargement)
(cross and uncross)
inferior cerebellar peduncle
paleocortex of cerebellum
superior cerebellar peduncle
B. Superficial sensory pathway
1. Pain, temperature and simple touch pathway of trunk and limbs
Skin of
1°neuron
central branches enter spinal cord
2°neuron
〈○
trunk
and limbs
spinal ganglia
LaminaⅠ,Ⅳ~Ⅶof spinal cord
╳
slope obliquely upward 1-2 segments, decussate through anterior white commissure
lateral spinothalamic tract (for pain and temperature ) in lateral funiculus
anterior spinothalamic tract ( for crude touch and pressure) in anterior funiculus
3°neurons
central thalamic radiation
superior and middle part of
postcentral gyrus, poterior
〈○
54
via posterior limb of internal capsule
VPL
part of paracentral lobule
2. Pain, temperature and simple touch pathway of head and face
Skin, mucosa
1°neuron
central processes enter pons
of head and
face
trigeminal ganglion
spinal tract of trigeminal nerve
2°neuron
╳
pontine nucleus of trigeminal never ( tactile )
trigeminal lemniscus
〈○
spinal nucleus of trigeminal nerve( pain and temperature )
3°neurons
central thalamic radiation
inferior part of postcentral gyrus
〈○
VPM
via posterior limb of internal capsule
C. Visual pathway and pupillary reflexes
※Visual filed: when both eyes are in use and directed
forward, the area which can be seen, that is the visual
field, may be divided into two parts, the nasal half and
temporal half of visual fields.
Because light must pass though the refractive media of
the eye the image of an object in the visual field on the
retina is reversed. The lens of each eye projects an
inverted and reversed visual field onto each retina. Thus ,
the temporal half of visual fields project onto the nasal halves of each retina; the nasal half of
visual fields project onto the temporal halves of each retina. In each case, light from the lower
half of the visual field falls on the upper retinal quadrants and light from the upper half of the
visual field on the lower retinal quadrants.
※ Pupillary reflex: When light is shone into one eye the pupils of both eyes constrict equally.
The response in the eye stimulated is the direct pupillary light reflex, while that in the opposite
55
eye is known as the indirect pupillary light reflex.
1. Visual pathway
1°neuron
Rod and cone cells
2°neuron
○
optic nerve
〈○
bipolar cells
ganglion cells
optic chiasma ( nasal fibers of retina cross, temporal fibers uncross ) ╳ → optic tract
3°neurons
optic radiation
〈○
visual area
lateral geniculate body
via posterior limb of internal capsule
The effects of lesions of the visual pathway
Site of lesion
Deficit
Left
Right
Left optic nerve
Blindness of left eye
●
○
Midline of optic chiasma
Bitemporal hemianopsia(tunnel vision)
◐
◑
Lateral part of optic chiasma
Nasal hemianopia of left eye
◑
○
Left optic tract
Right homonymous hemianopsia
◑
◑
2. Pupillary reflexes
retina→optic nerve→optic chiasma→both optic tracts→brachium of superior colliculus
both accessory oculomotor nuclei
〈○
〈○
sphincter pupil
〈○
pretectal area
ciliary ganglia
ciliary muscle
B. Auditory pathway
cochlear nerve
spinal organ
○
〈○
bipolar neuron of cochlear ganglion
╳ trapezoid body
cochlear nuclei
brachium of inferior colliculus
〈○
lateral lemniscus
inferior colliculus
hearing reflex
56
anterior horn
〈○
superior colliculus tectospinal tract
acoustic radiation
transverse temporal gyrus
〈○
medial geniculate body via posterior limb of internal capsule
Ⅱ. Motor pathway
A. Pyramidal system: consists of sets of two neurons
① Upper motor neuron: composed of pyramidal cells which located
in precentral gyrus and anterior part of paracentral lobule and
their axons which form pyramidal tract
② Lower motor neuron: composed of cranial motor nuclei or spinal
cord anterior horn and their axons
1. Corticospinal tract
upper motor neuron
corticospinal tract
○
pyramidal cells of superior and
via posterior limb of internal capsule,
middle parts of precentral gyrus
lateral part of middle 3/5 of crus cerebri,
and anterior part of paracentral
basilar part of pons,
lobule
pyramid of medulla oblongata
75%—90% of fibers cross ╳
decussation of pyramid
lateral corticospinal tract
10%—25% of fibers uncross
anterior corticospinal tract → some fibers cross and some uncross
lower motor neuron
57
〈○
skeletal muscles of trunk and limbs
motor neurons of anterior horn
3. Corticonuclear tract
upper motor neuron
corticonuclear tract
○
pyramidal cells of inferior
via genu of internal capsule,
part of precentral gyrus
medial part of middle 3/5 of crus cerebri
lower motor neuron
skeletal muscles of
〈○
bilateral oculomotor, trochlear, trigeminal motor, abducens,
head and neck
superior part of facial, ambiguus and accessory nuclei;
contralateral inferior part of facial and hypoglossal nuclei
B. Extrapyramidal system
1. Extrapyramidal system includes all descending ( motor ) tracts other than corticospinal
and corticonuclear tracts.
2. Function
a.
Regulate muscle tone
b. Coordinate muscular activities
c.
Maintain normal body posture and produce habitual and rhythmic movement
3. main pathways
cortex
↙
cortex
↖
↙
58
↖
corpus striatum → thalamus
pons
↑↓
thalamus
↘
substantia nigra
↗
cerebellum
↓
↓
reticular formation
red nucleus
↓
↓
reticulospinal tract
rubrospinal tract
↘
↙
motor neurons in anterior horn
Effects of Upper (UMN) and Lower (LMN) Motor Neuron Damage
UMN damage ( supranuclear
paralysis )
LMN damage ( infranuclear
paralysis )
Paralysis
Spastic
Flaccid
Muscle tone
Increased↑
Decreased↓
Deep tendon reflexes
Increased↑
Decreased
Pathological reflexes
Positive (＋)
Negatively (－)
amyotrophy
Indistinctly
Distinctly
Sdudy questions
Ⅰ. Single choice questions (there five choices on each question, only one is correct, please
circle the correct answer):
1. Which is the right about the corticospinal tract
A. arises from the cerebral cortex of the posterior central gyrus
B. passes through the genu of the internal capusule
C. About 50% fibers cross to the opposite side to form the pyramidal decussation
D. terminate in the anterior horns of gray matter of the spinal cord
E. some fibers terminate in lateral horn of gray matter of the spinal cord
2. The trigeminal lemniscus ends in
A.anterior thalamic nucleus
B. medial thalamic nucleus
C. anterior ventral nucleus
D.posteromedial ventral nucleus
E. posterolateral ventral nucleus
Ⅱ. Multiple choice questions (two to five choices are correct, please circle the correct answers):
1. The tracts being related to transmitting sensory impulses in spinal cord are
59
A. fasciculus gracilis
B. fasciculus cuneatus
C. posterior spinocerebellar tract
D. spinothalamic tract
E. anterior corticospinal tract
2. The structures that conduct the fine touch sensation of the trunk and limbs are
A. the medial leminiscus
B. the lateral leminiscus
C. the trigeminal leminiscus
D. the spinal leminiscus
E. the fasciculus gracilis and fasciculus cuneatus
Ⅲ. Answer the following questions
1. Show the way of the pupillary reflexes ( express by "→" )
2. Write the pain, temperature and simple touch pathway of the trunk and limbs (using the
arrows).
3. Write out the conscious proprioceptive and fine touch pathway of trunk and limbs (using
the arrows).
The Meninges and Blood Vessels of Brain
and
Spinal Cord, and Cerebrospinal Fluid
Learning Objectives
You should:

脑和脊髓的被膜

掌握硬脊膜的形态特征、硬膜外隙的位置与内容。

了解脊髓蛛网膜、软脊膜的形态特点。掌握蛛网膜下隙的位置、内容及终池的位
置。

掌握硬脑膜的形态特点。掌握硬脑膜形成的特殊结构（大脑镰、小脑幕、鞍膈）
的位置。掌握硬脑膜窦的名称、位置。掌握海绵窦的位置、穿经海绵窦的结构及
海绵窦的交通。
60

了解脑蛛网膜和软脊膜的结构特点。掌握小脑延髓池的位置。了解其它蛛网膜下
池的位置。


了解颅内、外静脉的交通。
脊髓和脑的血管
 掌握脑的动脉来源、颈内动脉和椎动脉的行程及其主要分支。大脑前、中、后动
脉的发起和分布。


掌握大脑动脉环的组成和位置。

了解大脑浅、深静脉的回流概况。

了解脊髓的动脉和静脉。
脑脊液及其循环

掌握脑脊液的产生部位和循环途径。
The spinal cord and brain are surrounded by three membranes, the meninges. Named
from the outside inward they are the dura mater, arachnoid, and pia mater.
Ⅰ. Dura mater
Ⅰ) Spinal dura mater: tough and thick protective sheath of connective tissue
1. Characters
⑴Above, attached to circumference of foramen magnum
⑵ Below, becomes thinner at level of S2, invests filum terminale to attach at back of
coccyx
⑶ On each side, continuous with external membrane of spinal nerves at intervertebral
foramina
2.
Epidural space
⑴ Position: lies between spinal dura mater and
periosteum of vertebral canal
⑵ Contents: a quantity of loose connective
tissue, fat, lymphatic vessels and vertebral
venous plexus, the spinal nerves on each
side pass through the epidural space which is applicable for block anesthesia
3. Subdural space: a potential space lies between spinal dura mater and spinal arachnoid
61
mater
Ⅱ) Cerebral dural mater
1. Characters
⑴ A thick and dense inelastic membrane that composed of two layers, an inner or
meningeal and outer or endosteal
⑵ It is in loose contact with calvaria, and most strongly adherent to base of skull
2. Four septa：meningeal layer of dura mater gives rise to four septa assist in restricting
rotatory displacement of the brain
⑴ Cerebral falx: a sickle-shaped fold lying in
midline between two cerebral hemispheres,
with free inferior margin just above
corpus callosum, attaches to frontal crest
and crista galli anteriorly and join
tentorium of cerebellum posteriorly
⑵
Tentorium
of
cerebellum:
a
crescent-shaped fold that lies between cerebellum and cerebrum; in front there is
a gap, the tentorial incisure, for passage of midbrain
⑶ Cerebellar falx: a small, sickle-shapes fold that projects forward between two
cerebellar hemispheres
⑷ Diaphragma sellae: a small circular fold that coves hypophyseal fossa, a small
opening in its center allows passage of stalk of hypophysis
3. Sinuses of dura mater: situated between layers of dura mater, lined by endothelium,
and their walls are devoid of muscular tissue, and contain no valves
⑴ Superior sagittal sinus: occupies upper border of cerebral falx
⑵ Inferior sagittal sinus: lies in free lower margin of cerebral falx
⑶ Straight sinus: occupies line of junction of cerebral falx with tentorium of
cerebellum
⑷ Confluence of sinus: is dilated junction of superior sagittal sinus and straight
sinus
⑸ Transverse sinus: situated in transverse sulcus
⑹ Sigmoid sinus: situated in sigmoid sulcus and is continuous with internal jugular
vein at internal jugular foramen
⑺ Cavernous sinus
62
①Position: lies on each side of sella turcica
②Relations of cavernous sinus: internal
carotid artery and abducent nerve run
through the sinus; oculomotor and
trochlear nerves and ophthalmic and
maxillary divisions of trigeminal nerve
liein the lateral wall of the sinus, between the endothelium and dura
⑻ Superior and inferior petrosal sinuses: lie at superior and inferior of petrous
temporal bone, each superior petrosal sinus drains cavernous sinus into
transverse sinus, and each inferior petrosal sinus drains cavernous sinus into
internal jugular vein
The flowing of the blood in dural sinus
superior sagittal sinus
inferior sagittal sinus → straight sinus → confluence of sinus → transverse sinus
→superior petrosal sinus
cavernous sinus
sigmoid sinus
→inferior petrosal sinus
internal jugular vein
Ⅱ. Arachnoid mater
Ⅰ) Characters: a delicate membrane enveloping brain and spinal cord and lying between pia
mater internally and dura mater externally. It is attached to the underlying pia by
numerous arachnoid trabeculae, creating a considerable cavity between the arachnoid
and the pial layer.
II) Spinal arachnoid mater: a thin, delicate, tubular membran loosely investing spinal
cord; above, it is continuous with cerebral arachnoid mater
III) Cerebral arachnoid mater
63
1. Characters: a delicate membrane covering brain loosely, passing over sulci and
entering only cerebral longitudinal and transverse fissures
2. Arachnoid granulations: in certain areas the arachnoid projects into sinuses of dura
mater to form arachnoid granulations which serve as sites where cerebrospinal fluid
diffuses into bloodstream
IV) Subarachnoid space
1. Position: lies between pia and arachnoid maters containing cerebrospinal fluid
2. Subarachnoid cisterns
⑴ Terminal cistern: the largest part of subarachnoid space extending from
termination of spinal cord to level of S2, where it is occupied by nerves of
cauda equina, so it is the best site for a lumbar puncture
⑵ Cerebellomedullary cistern: lies between cerebellum and medulla
⑶ Interpeduncular cistern: lies between two crus cerebri
⑷ Pontine cistern: lies in front of pons
⑸ Superior cistern: lies between the splenium of corpus callosum and cerebellum
Ⅲ. Pia mater
Ⅰ) Characters: a delicate vascular membrane that closely invests the brain and spinal cord
covering gyri and descending into deepest sulci
Ⅱ) Spinal pia mater
1. Denticulate ligament: consist of 21 pairs triangular ligaments extending from spinal
cord on each side between anterior and posterior roots of spinal nerves to spinal dura
mate; these ligaments help to fix position of spinal cord.
2. Filum terminale: an extension of pia beyond conus medullaris
Ⅲ) Cerebral pia mater: closely invests brain surface, continues as a sheath around the small
vessels entering the brain; in some areas the pia invaginates into ventricles to take part in
the formation of choroids plexus, which secretes cerebrospinal fluid.
Ⅳ. Circulation of cerebrospinal fluid (CSF)
Ⅰ) Cerebrospinal fluid is a clear colorless fluid, which acts as
a transport medium for nutrients and vaster products and
provides a protective fluid cushion for the central
nervous system.
Ⅱ) Production: The CSF is produced by the choroids plexuses
within the lateral, third and fourth ventricles.
64
Ⅲ) Circulation: CSF drains from lateral ventricle through interventricular foramina into third
ventricle, then through mesencephalic aqueduct into fourth ventricle; fluid escapes from
fourth ventricle through its openings, median and two lateral apertures of fourth
ventricle , and enters the subarachnoid space; after circulating around brain and spinal
cord, it is reabsorbed into dural venous sinuses, particularly superior sagittal sinus,
through arachnoid granulations.
interventricular foramina
CSF drains from lateral ventricle
third ventricle
mesencephalic aqueduct
median and two lateral apertures
fourth ventricle
arachnoid granulations
subarachnoid space
superior sagittal sinus
vein
Ⅴ. Blood vessels of brain and spinal cord
Ⅰ) Arteries of brain
1. Two sources
⑴ Internal carotid artery: supplies anterior 2/3 of cerebral hemisphere and parts of
diencephalon
⑵ Vertebral artery: supplies posterior 1/3 of cerebral hemisphere and parts of
diencephalon, brain stem and cerebellum
2. Internal carotid artery
⑴ Course: arises from common carotid artery and passes upward through carotid
canal to enter cranial cavity and passes cavernous sinus to the brain
⑵ branches:
① Anterior cerebral artery: runs forward
and medially and enters longitudinal
fissure of cerebrum. It is joined the
fellow of the opposite side by the
anterior communicating artery. It curves backward over the corpus
callosum.
a) Cortical branches: supply all medial surface of the cerebral cortex as far
back as the parietooccipital sulcus and superior border of the suprolateral
65
surface of the cerebral hemisphere
b) Central branches: supply caudate nucleus, anterior part of lentiform
nucleus and anterior limb of internal capsule
② Middle cerebral artery: the largest branch
of internal carotid artery, runs laterally in
lateral sulcus
a) Cortical branches: supply most of
superolateral
surface
of
cerebral
hemisphere and insular lobe
b) Central branches: supply lentiform and caudate nuclei, genu and posterior
limb of internal capsule (lenticulostriate artery)
③ Anterior choroidal artery: passes backward, enters inferior horn of lateral
ventricle, and ends in choroid plexus. It supplies lateral geniculate body,
posterior limb of internal capsule, middle 3/5 of crus cerebri,and globus
pallidus
④ Posterior communicating artery: runs backward to join posterior cerebral
artery
2. Vertebral artery
⑴ Course: arises from subclavian artery and ascends through transverse foramina
of sixth through first cervical vertebrae. It enters skull through foramen
magnum and passes upward, forward, and medially on medulla oblongata. At
lower border of pons it joints the vessel of the opposite side to form basilar
artery.
⑵Cranial branches of vertebral artery includes:
① Anterior and posterior spinal arteries
② Posterior inferior cerebellar artery: supplies posterior part of cerebellum
and postrolateral part of medulla
⑶Branches of basilar artery
① Anterior inferior cerebral artery
② Labyrinthine artery
③ Pontine arteries
④ Superior cerebellar artery
66
⑤ Posterior cerebral artery: on
each side curves laterally and
backward around midbrain
a) Cortical branches: supply
medial and inferior surfaces of temporal lobe and occipital lobe
b) Central branches: supply dorsal thalamus, medial and lateral
geniculate bodies, hypothalamus and subthalamus
3. Cerebral arterial circle ( circle of Willis )
⑴ Formation: formed by anterior
communicating artery, both anterior
cerebral arteries, internal carotid arteries,
posterior communicating arteries, and
posterior cerebral arteries
⑵ Position: lies on sella turcica around optic
chiasma, tuber cinereum and mamillary
bodies
This is an anastomosis between branches of the internal carotid arteries and the
vertebral arteries. It allows blood entering either the carotid or vertebral artery to
flow to any part of both cerebral hemispheres.
Ⅱ) Veins of brain
1.
Superficial cerebral veins: drain blood from cortex and subcortical medullary
substance and empty into adjacent sinuses of dura mater
2.
Deep cerebral veins: drain deeper parts of hemispheres, basal nuclei, internal
capsule, diencephalon and choroid plexus, ultimately form great cerebral vein which
enter straight sinus
Ⅲ) Blood vessels of spinal cord
1. Arteries of spinal cord
67
⑴ Two sources
①
Anterior and posterior spinal arteries
②
Branches of segmental arteries: radicular arteries of posterior intercostals
arteries, lumbar arteries, and lateral sacral arteries
⑵ Damage area: T1~T4, ventral part of L1
⑶ The spinal cord is surrounded by a vascular ring ( vasocorona ), from which
vessels extend into the white matter. The anterior spinal artery supplies the
anterior horn, the base of posterior horns and the great part of anterolateral
funiculus. The posterior spinal arteries supply the posterior funiculus and the
remainder of the posterior horns. The marginal zone of anterolateral funiculus is
supplied by plexus of the vasocorona.
2. Spinal veins: have a general distribution similar to that of spinal artery, and drain into
internal vertebral venous plexus
Sdudy questions
Ⅰ. Single choice questions (there five choices on each question, only one is correct, please
circle the correct answer):
1. The blood supply of motor speech area comes from
A. anterior cerebral artery
B. middle cerebral artery
C. posterior cerbral artery
D. vertebral artery
E. basilar artery
2. Subarachnoid space
A. lies between arachnoid and pia maters
B. lies between arachnoid and dura maters
C. lies between dura and pia maters
D. lies between spinal dura mater and periosteum of vertebral canal
E. contains a quantity of loose connective tissue, fat, lymphatic vessels and vertebral
venous plexus,
Ⅱ. Multiple choice questions (two to five choices are correct, please circle the correct answers):
1. The epidual space
A. is filled with cerebrospinal fluid.
68
B. is between the spinal dura matter and the periosteum of the vertebral canal.
C. is not open into the cranial cavity.
D. contains loose areolar tissue,venous plexus, lymphatic and roots of spinal nerve
E. all above are incorrect.
2. The cerebral arterial circle is formed by
A. the anterior cerebral a.
B. the middle cerebral a.
C. the posterior cerebral a.
D. the anterior communicating a.
E. the posterior communicating a.
Ⅲ. Answer the following questions
1. Describe the position and formation of cerebral arterial circle.
2. Write out the producting place and the circulation of cerebrosprinal fluid (to express in
“→” ).
3. Write out the names of dural sinus, and the flowing of the blood in them ( the direction can
be used by "→" ).
Part ⅢThe Peripheral Nervous System
The Spinal Nerves
Learning Objectives
You should:

掌握脊神经的构成、区分、纤维成份、分支及分布概况。

掌握颈丛的组成、位置。了解颈丛皮支的名称、浅出部位及分布。掌握膈神经的组成
及在颈部的行径。

掌握臂丛的组成、位置、分支。掌握肌皮神经、正中神经、尺神经、桡神经、腋神经
的分支和分布。了解其行径及损伤后的主要表现。了解胸长神经、胸背神经的分布。]

掌握胸神经前支的分布概况及其皮支的分布特点。

掌握腰丛的组成、位置、主要分支及分布。掌握股神经、闭孔神经的行径、分支和分
69
布。

掌握骶丛的组成、位置及主要分支。掌握坐骨神经的行径、分支及分布。了解腓总神
经、腓深神经、腓浅神经和胫神经的行径，掌握腓深神经、腓浅神经和胫神经的分布。
了解损伤后的临床表现。
Ⅰ. General description
There are 31 pairs spinal nerves: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal
nerve.
Ⅰ) Formation: each spinal nerve is formed by union of anterior and posterior roots at
intervertebral foramen
1. The anterior root contains motor fibers for skeletal muscles. Those from T1 to L2 contain
sympathetic fibers; S2 to S4 also contain parasympathetic fibers.
2. The posterior root contains sensory fibers whose cell bodies are in the spinal ganglion.
Ⅱ) Functional components
1. Somatic efferent nerve fibers (SE): fibers
that transmit motor impulses from spinal
cord to skeletal muscles.
2. Visceral efferent nerve fibers (VE): fibers
that transmit motor impulses from spinal
cord to smooth muscles, cardiac muscle and
glands.
3. Somatic afferent nerve fibers (SA): fibers that transmit exteroceptive and proprioceptive
impulses from body to spinal cord
4. Visceral afferent nerve fibers (VA): fibers that transmit interoceptive impulses from the
viscera to spinal cord
Ⅲ) branches of spinal nerves
1. Anterior branch: largest , innervates anterolateral body wall and limbs，the great nerve
plexus, e.g. the cervical, brachial, lumbar, and sacral, are formed by anterior rami
2. Posterior branch: innervates the back of the trunk
3. Communicating branch: connect the spinal nerve to the sympathetic trunk
4. Meningeal branch: re-enters vertebral canal through intervertebral foramen to dura mater
Ⅱ. Cervical plexus
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Ⅰ) Formation: formed by anterior rami of C1-C4 spinal nerves
Ⅱ) Position: lies in front of the origin of levator scapulae and
scalenus medius and deep to the superior part of the
sternocleidomastoid
Ⅲ) Branches
1. Cutaneous branches: emerge around middle of posterior
border of sternocleidomastoid, to supply skin of neck and
scalp between auricle and external occipital protuberance
Nerve
Course and ditribution
Lesser occipital
Ascends along posterior border of the sternocleidomastoid, to supply skin
behind auricle
Greet auricular
Ascends across sternocleiodomastoid in company with eternal jugular vein
to supply skin cover angle of mandible, parotid gland and mastoid
process and on both surface of auricle
Transverse nerve
of neck
Passes forward across sternocleidomastoid
to supply skin in anterior
surface of neck
Supraclavicular
Pass downwards over clavicle and supply skin down as far as second
intercostals space
2. Muscular branches: supply the deep muscles of neck
3. Phrenic nerve (anterior rami of C3-C5) to
diaphragm (motor and sensory):
(1) Descends over scalenus anterior to enter thorax
(2) Accompanied by pericardiophrenic vessels and
passes
anterior
to
lung
roots
between
mediastinal pleura and pericardium to supply
motor and sensory innervation to diaphragm
(3) Sensory fibers supply to pleurae, pericardium
and peritoneum of diaphragm; usually right phrenic nerve may be distributed on live,
gallbladder and biliary system.
4. Ansa cervicalis: hypoglossal nerve gives off superior root of ansa (descendens
71
hypoglossi), composed of fibers picked up from nerve C1; it joins inferior root of ansa
(descendens cervicalis, C2and C3) to form a loop, the ansa cervicalis, which supplies
infrahyoid muscles
III. Brachial plexus
I)
Formation: formed by anterior rami of C5-C8 and
T1 spinal nerves
II) Position: passes through the scalene fissure to
posterosuperior of subclavian artery,
then enters
the axilla to form three cords
III) Main branche
musculocutaneous n. → lateral antebrachial cutaneous n.
Lateral cord
lateral root
anterior interosseous n.
median n.
medial root
Medial cord
recurrent n.
common palmar digital n.
ulnar n.
medial brachial and medial antebrachial cutaneous n.
radial n. → superficial and deep branches
Posterior cord
axillary n.
thoracodorsal n. → latissimus dorsi
Long thoracic n. → serratus anterior
Nerve
Distribution
Injury
Musculocutaneous
Biceps brachii, brachalis and coracobrachialis ‘BBC
nerve’; skin on anterior aspect of forearm
Median
Flexor of forearm except brachioradialis, flexor carpi
Apehand
ulnaris and ulnar half of flexor digitorum profundus,
thenar except adductor pollicis, first two lumbricals;
skin of thenar, central part of palm, palmar aspect of
radial three and one-half fingers, including middle
and distal fingers on dorsum
Ulnar
Flexor carpi ulnaris, ulnar half of flexor digitorum
72
clawhand
profundus, hypothenar muscles, interossei, 3rd and
4th lumbricals and adductor pollicis; skin of
hypothenar, palmar surface of ulnar one and one-half
fingers, ulnar half of dorsum of hand, posterior
aspect of ulnar two and one-half fingers
Radial
Extensor muscles of arm and forearm, brachioradialis;
Wristdrop
skin on back of arm, forearm, and radial side of
dorsum of hand and radial two and one-half fingers
Axillary
Deltoid and teres minor muscle; skin over deltoid and
upper posterior aspect of arm
IV. Anterior branches of thoracic nerves
I) Intercostal nerves (anterior rami of T1- T11): runs forward
inferiorly to intercostals vessels in costal groove of
corresponding
rib,
between
intercostals
externi
and
intercostals interni; first six nerves are distributed within
their intercostals space, lower five intercostals nerves leave
anterior ends of their intercostals spaces to enter abdominal
wall
II) Subcostal nerve (anterior ramus of T12): follows inferior border of T12 rib and passes into
abdominal wall
III) Distribution: distributed to intercostales and anterolateral abdominal muscles, skin of
thoracic and abdominal wall, parietal pleura and peritoneum
★ The segmental innervation of anterior surface of trunk
Segment
Supply the level
T2
Sternal angle
T4
Nipple
T6
Xiphoid process
T8
Costal arch
T10
Umbilicus
T12
Midpoint between umbilicus and symphysis pubis
73
V. Lumbar plexus
I) Formation: formed by anterior rami of L1-L3, a part of anterior
rami of T12and L4
II) Position: lies within substance of psoas major
III) Branches
Nerve
Course and distribution
Iliohypogastric
Supplies lower part of anterior abdominal wall
Ilioinguinal
Passes through inguinal canal to supply skin of the groin and scrotum
Lateral
femoral
cutaneous
Femoral
Passes deep to inguinal ligament, 2-3cm medial to anterior superior iliac
spine; supplies skin on anterior and lateral aspects of thigh
Runs downward and laterally between psoas and iliacus, passes deep to
inguinal ligament; supplies anterior thigh muscles (quadriceps, sartorius
and pectineus), hip and knee joint, and skin on anteromedial side of
thigh, saphenous nerve is distributed to skin of medial side of leg and
foot
Obturator
Enters thigh through obturator foramen; supplies medial group of muscles
of thigh, obturator externus, and skin of medial side of thigh
Genitofemoral
Descends on anterior surface of psoas major and divides into genital and
femoral branches; femoral branch supplies skin over femoral triangle;
genital branch supplies scrotum or greater lip pudendum
VI. Sacral plexus
I) Formation: formed by anterior rami of L4 and L5 spinal
nerves (the lumbrosacral trunk) and anterior rami of sacral
and coccygeal nerves
II) position: lies in pelvic cavity, anterior to sacrum and
piriformis
III) Branches
74
Nerve
Course and distribution
Superior
Leaves pelvis through suprapiriform foramen and passes between gluteus
gluteal
Inferior
medius and minimus to supplies these muscles and tensor fasciae latae
Leaves pelvis through infrapiriform foramen; and supplies gluteus maximus
gluteal
Pudendal
Leaves pelvis through infrapiniform foramen, crosses ischial spine with internal
pudendal artery and immediately reenter perineum through lesser sciatic
foramen, then passes forward in pudendal canal by means of it branches
supplies external anal sphincter and the muscles and skin of the perineum;
main branches are anal nerve, perineal nerve, dorsal nerve of penis (clitoris)
Posterior
Leaves pelvis through infrapiniform foramen, runs deep to gluteus maximus
femoral
and emerges from its inferior border to supply skin of buttock and then
cutaneou
surface skin over posterior of thigh and calf
Sciatic
Leaves pelvis through infrapiriform foramen to enter gluteal region, runs
inferiorly laterally deep to gluteus maximus, passing midway between the
greater trochanter of femur and ischial tuberosity to back of thigh, lying deep
to long head of biceps femoris, normally divided into tibial and common
peroneal nerves just above popliteal fossa; innervates semitendinosus,
semimembranosus and biceps femoris and has articular branches to hip and
knee joints
Common
peroneal
Arises at apex of popliteal fossa and follows medial border of biceps femoris
and its tendon; passes over posterior aspect of head of fibula and then winds
around neck of fibula, deep to peroneus longus, where it divides intodeep and
superficial peroneal nerves; supplies skin on posterolateral part of leg via its
branch—lateral sural cutaneous nerve
Deep
peroneal
Arises between peroneus longus and neck of fibula; descends on interosseous
membrane and enters dorsum of foot; supplies anterior muscles of leg, and
skin of first interdigital cleft
Superficial
peroneal
Arises between peroneus longus and neck of fibula and descends in lateral
compartment of leg; supplies peroneus longus and brevis and skin on anterior
surface of leg and dorsum of foot
Tibial
Decends through popliteal fossa and lies on popliteus; then runs inferiorly with
posterior tibial vessels and terminates beneath flexor retinaculum by dividing
75
into medial and lateral plantar nerves; supplies posterior muscles of leg and
knee joint
Sdudy questions
Ⅰ. Single choice questions (there five choices on each question, only one is correct, please
circle the correct answer):
1．Which is false about sacral plexus
A. It is formed by anterior branches from the part of 4th lumbar nerve to coccygeal nerve
B. It lies anterior to the sacrum and piriformis in the pelvic cavity
C. It gives out posterior femoral cutaneous nerve to posterior surface skin of thigh
D. It gives out sciatic nerve to innervate the all muscles of thigh
E. It gives out inferior gluteal nerve to innervatethe gluteus maximus
2．If the plantar flexion at ankle joint is not permitted, which nerve may be damaged?
A. deep peroneal nerve
B. superficial peroneal nerve
C. tibial nerve
D. obturator nerve
E. femoral nerve
Ⅱ. Multiple choice questions (two to five choices are correct, please circle the correct answers):
1．Which nerves distribute to the skin of hand
A. radial nerve
B. axillary nerve
C. musculocutaneus nerve
D. ulnar nerve
E. median nerve
2．Which nerves arise from the lumbar plexus
A. femoral nerve
B. sciatic nerve
C. obturator nerve
D. ilioinguinal nerve
E. lateral femoral cutaneous nerve
Ⅲ. Answer the following questions
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1．Describe the origin, course, branches and distribution ( muscle groups ) of the sciatic nerve.
2．Describe the origin, course and distribution of the phrenic nerve.
3．Describe the origin and distribution of the median, ulnar and radial nerves.
The Cranial Nerves
Learning Objectives
You should:

掌握脑神经的名称、性质、连脑部位、进出颅的部位。

了解嗅神经的功能性质和分布。

掌握视神经的功能性质、行程及被膜。

掌握动眼神经的纤维成份、行程及分布。了解睫状神经节的位置与性质。

掌握滑车神经的分布。

掌握三叉神经的纤维成份、主要分支和分布概况；三叉神经节的位置与性质。

掌握展神经的分布。
77

掌握面神经的纤维成份、主要分支的分布概况。了解翼腭神经节和下颌下神经节的位
置与性质。

掌握前庭蜗神经的功能性质。

掌握舌咽神经的纤维成份、主要分支的分布概况。了解耳神经节的位置与性质。

掌握迷走神经的纤维成份、主干行程、主要分支及分布概况。

掌握副神经和舌下神经的分布概况。
Ⅰ. Names of cranial nerves
There are twelve pairs of cranial nerves which leave the brain and
pass through foramina in the skull. The cranial nerves named from 1 to
12 according to the anterior to posterior order in which they emerge
from the brain. Cranial nerves have been given both names and
numbers, and Roman numbers should be used. The cranial nerves are
as follows:
ⅠOlfactory nerve
ⅦFacial nerve
ⅡOptic nerve
ⅧVestibulocochlear nerve
ⅢOculomotor nerve
ⅨGlossopharyngeal nerve
ⅣTrochlear nerve
ⅩVagus nerve
ⅤTrigeminal nerve
ⅪAccessory nerve
ⅥAbducent nerve
ⅫHypoglossal nerve
Ⅱ. Functional components
1. General somatic afferent fibers (GSA): transmit exteroceptive and proprioceptive
impulses from head and face to somatic sensory nuclei
2. Special somatic afferent fibers (SSA): transmit sensory impulses from special sense
organs of vision, equilibrium and hearing to the brain
3. General visceral afferent fibers (GVA): transmit interoceptive impulses from the viscera
to the visceral sensory nuclei
4. Special visceral afferent fibers (SVA): transmit sensory impulses from special sense
organs of smell and taste to the brain
5. General somatic efferent fibers (GSE): innervate skeletal muscles of eye and tongue
6. General visceral efferent fibers (GVE): transmit motor impulses from the general
visceral motor nuclei and relayed in parasympathetic ganglions. The postganglionic
78
fibers supply cardiac muscles，smooth muscles and glands
7. Special visceral efferent fibers (SVE): transmit motor impulses from the brain to
skeletal muscles derived from brachial (gill) arches of embryo. These include the
muscles of mastication, facial expression and swallowing.
According to the components and functions the 12 pairs of cranial nerves are divided into
three types: ①some cranial nerves contain only afferent (sensory) fibers and thus are called
sensory cranial nerves. ②some cranial nerves contain only efferent (motor) fibers and thus are
called motor cranial nerves. ③the remainder contain both sensory and motor fibers and are
referred to as mixed nerves.
Ⅲ. Sensory cranial nerves
Nerve
Ⅰ
Location of cell body
Cranial
and axon categories
exit
Olfactory cells (SVA)
Cribriform
Terminal nuclei
Main action
Olfactory bulb
Smell
Lateral geniculate
Vision
foramina
Ⅱ
Ganglion cells (SSA)
Optic canal
body
Ⅷ
Vestibular ganglion(SSA)
Internal
Cochlear ganglion (SSA)
acoustic
Vestibular nuclei
Equilibrium
Cochlear nuclei
Hearing
meatus
Ⅳ. Motor cranial nerves
Nerve
Nucleus of origin and
Cranial exit
Main action
Superior orbital
Motor to superior, inferior and medial
fissure
recti; inferior obliquus; levator
axon categories
Ⅲ
Nucleus of oculomotor
(GSE)
palpebrae superioris; raises upper
eyelid;tuns eyeball
superiorly,inferiorly, and medially
Accessory nucleus of
Parasympathetic innervation
oculomotor (GVE)
sphincter pupillea and ciliary muscle;
constricts pupil and accommodates
lens of eye
79
Ⅳ
Ⅵ
Ⅺ
Nucleus of trochlear
Superior orbital
nerve (GSE)
fissure
Nucleus of abducent
Superior orbital
nerve (GSE)
fissure
Nucleus of accessory
Jugular foramen
Motor to superior obliquus
Motor to lateral rectus
Motor to sternocleidomastoid and
nerve (SVE)
Ⅻ
Nucleus of hypoglossal
trapezius
Hypoglossal canal
Moror to muscles of tongue
nerve( GSE)
Ciliary ganglion: lies between optic nerve and lateral rectus
Ⅲ. Mixed cranial nerves
A. Trigeminal nerve (Ⅴ)
1. Components of fibers
a)
SVE fibers: originate from motor nucleus of trigeminal nerve, and supply
masticatory muscles
b) GSA fibers: transmit facial sensation to sensory nuclei of trigeminal nerve, the
GSA fibers have their cell bodies in trigeminal ganglion, which lies on the apex of
petrous part of temporal bone
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2. Branches: There are three divisions, each of which has several branches.
a) Ophthalmic nerve (Ⅴ1, sensory)
⑴Leave the skull through the superior orbital fissure, to enter orbital cavity
⑵Branches
① Frontal nerve: divides into supratrochlear nerve and supraorbital nerve
② Lacrimal nerve
③ Nasociliary nerve
⑶Distribution: sensation from cerebral dura mater, visual organ, mucosa of nose, skin
above the eye and back of nose
b) Maxillary nerve (Ⅴ2, sensory)
⑴ Leave skull through foramen rotundum, crosses pterygopalatine fossa, passes
through inferior orbital fissure to enter orbital cavity, the nerve is now called
infraorbital nerve, and it runs forward on floor of orbit, fist in infraorbital groove
and then in infraorbital canal, and emerges through infraorbital foramen
⑵Branches
①Infraorbital nerve
②Zygomatic nerve
③Superior alveolar nerve
④Pterygopalatine nerve
⑶ Distribution: sensation from cerebral dura mater, maxillary teeth , mucosa of nose
and mouth, skin between eye and mouth
c) Mandibular nerve (Ⅴ3, mixed)
⑴Leave the skull through the foramen ovale to enter the infratemporal fossa
⑵Branches
①Auriculotemporal nerve
②Buccal nerve
③Lingual nerve
④ Inferior alveolar nerve: pass though the mandibular foramen to enter
mandibular canal, and emerges through mental foramen, the nerve is now
called mental nerve
⑤Nerve of masticatory muscles
⑶ Distribution: sensation from cerebral dura mater,
teeth and gum of lower jaw, mucosa of floor of
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mouth and anterior 2/3 of tongue, skin of auricular and temporal regions and
below the mouth; motor to masticatory muscles, mylohyoid, and anterior belly of
digastric
B. Facial nerve (Ⅶ)
1. Components of fibers
a) SVE fibers originate from nucleus of facial nerve, and supply facial muscles
b)
GVE fibers derived from superior salivatory nucleus and relayed in
pterygopalatine ganglion and submandibular ganglion. The postganglionic fibers
supply lacrimal, submandibular and sublingual glands
c) SVA fiber from taste buds of anterior two-thirds of tongue which cell bodies are in
the geniculate ganglion of the facial nerve and end by synapsing with cells of
nucleus of solitary tract
d) GSA fibers from skin of external ear
2. Course: leaves skull through internal acoustic meatus, facial canal and stylomastoid
foramen, it then enters parotid gland where it divides into five branches which supply
facial muscles
3. Branches within the facial canal
a) Chorda tympani: joins lingual branch of mandibular nerve
⑴to taste buds on anterior two-thirds of tongue
⑵ relayed in submandibular ganglion, the postganglionic fibers supply
submandibular and sublingual glands
b) Greater petrosal nerve: GVE fibers pass to pterygopalatine ganglion and there
relayed through the zygomatic and lacrimal nerves to lacrimal gland
c) stapedial nerve: to stapedius
4. Branches outside of facial canal: facial nerve
enters parotid gland and divides into its five
terminal
branches
for
muscles
of
expression
a) Temporal
b) Zygomatic
c) Buccal
d) Marginal mandibular
e) Cervical
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facial
5. Pterygopalatine ganglion: lies in pterygopalatine fossa under maxillary nerve
6. submandibular ganglion: lies between lingual nerve and submandibular gland
C. Glossopharyngeal nerve (Ⅸ)
1. Components of fibers
a) SVE fibers: originate from nucleus ambiguus, and supply stylopharygeus
b) GVE fibers: arise from inferior salivatory nucleus and ralyed in otic ganglion, the
postganglionic fibers supply parotid gland
c) SVA fibers: arise from the cells of inferior ganglion, the central processes of these
cells terminate in nucleus of solitary tract, the peripheral processes supply the taste
buds on posterior third of tongue
d) GVA fibers: visceral sensation from mucosa of posterior third of tongue, pharynx,
auditory tube and tympanic cavity, carotid sinus and glomus, and end by synapsing
with cells of nucleus of solitary tract
e) GSA fibers: sensation from skin of posterior surface of auricle
2. Course: leaves the skull via jugular foramen
3. Branches
a)
Lingual branches: to taste buds and mucosa of
posterior third of tongue
b)
Pharyngeal branches: take part in forming the
pharyngeal plexus
c)
Tympanic nerve: GVE fibers via tympanic and lesser petrosal nerves to otic
ganglion, with postganglionic fibers via auriculotemporal (Ⅴ3) to parotid gland
d) Carotid sinus branch: innervations to both carotid sinus and glomus
e) Others: tonsillar and stylophayngeal branches
f) Otic ganglion: situated just below foramen ovale
D. Vagus nerve (Ⅹ)
1. components of fibers
a)
GVE fibers: originate from dorsal nucleus of vagus nerve, synapse in
parasympathetic ganglion, short postganglionic fibers innervate cardiac muscles,
smooth muscles and glands of viscera
b) SVE fibers: originate from ambiguus, to muscles of pharynx and larynx
c) GVA fibers: carry impulse from viscera in neck, thoracic and abdominal cavity to
nucleus of solitary tract
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d) GSA fiber: sensation from auricle, external acoustic meatus and cerebral dura mater
2. Course:
a) Exits the skull from jugular foramen
b) Descends in the neck in carotid sheath between internal (or common) carotid artery
and internal jugular vein
c) Right vagus nerve
⑴ Enter thoracic inlet on right side of trachea
⑵ Travels downward posterior to right brachiocephalic vein and superior vena
cava
⑶ Passes posterior to right lung root
⑷ Forms posterior esophageal plexus
⑸ Forms posterior vagal trunk at esophageal hiatus where it leaves thorax and
passes into abdominal cavity, then divides into posterior gastric and celiac
branches
d) Left vagus nerve
⑴ Enter thoracic inlet between left common carotid and left subclavian arteries,
posterior to left brachiocephalic vein
⑵Crosses aortic arch where left recurrent laryngeal nerve branches off
⑶ Passes posterior to left lung root
⑷ Forms anterior esophageal plexus
⑸ Forms anterior vagal trunk at esophageal hiatus where it leaves thorax and
passes into abdominal cavity , then divides into anterior gastric and hepatic
branches
3. Branches in neck
a) Superior laryngeal nerve: passes down side of pharynx
and given rise to
⑴ Internal branch, which pierces thyrohyoid membrane
to innervates mucous membrane of larynx above
fissure of glottis
⑵ External branch, which innervates cricothyroid
b) Cervical cardiac branches : descending to terminate in
cardiac plexus
c) Others: auricular, pharyngeal and meningeal branches
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4. Branches in thorax
a) Recurrent laryngeal nerves
⑴ Right one hooks around right subclavian artery, left
one hooks aortic arch
⑵Both ascend in tracheo-esophageal groove
⑶ Nerves enter larynx posterior to cricothyroid joint, the
nerve is now called inferior laryngeal nerve
⑷ Innervations: laryngeal mucosa below fissure of
glottis , all laryngeal laryngeal muscles except
cricothyroid
b) Bronchial and esophageal branches
5. Branches in abdomen
a) Anterior and posterior gastric branches
⑴ Run close to lesser curvature and innervate anterior
and posterior surfaces of stomach
⑵ As far as pyloric antrum to fan out into branches in
a way like the digits of a crow’s foot to supply
pyloric part
b) Hepatic branches: join hepatic plexus and then supply liver and gallbladder
c) Celiac branches: send branches to celiac plexus to be distributed with sympathetic
fibers to liver, pancreas, spleen, kidneys, intestine as far as left colic flexure
Sdudy questions
Ⅰ. Single choice questions (there five choices on each question, only one is correct, please
circle the correct answer):
1. The nerves passing through the jugular foramen
A. glossopharyngeal nerve, facial nerve and vagus nerve
B. glossopharyngeal nerve, acessory nerve and vagus nerve
C. glossopharyngeal nerve, hypoglossal nerve and vagus nerve
D. glossopharyngeal nerve, hypoglossal nerve and acessory nerve
E. glossopharyngeal nerve, hypoglossal nerve and vestibulocochlear nerve
2. The facial nerve
A. general visceral efferent fibers originate from inferior salivatory nucleus
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B. emerges from the bulbopontine sulcus
C. leave the skull through the foramen rutundum
D. supplies the skin of the face
E. supplies parotid gland
Ⅱ. Multiple choice questions (two to five choices are correct, please circle the correct answers):
1. General visceral efferent fibers of the facial nerve supply
A. parotid fland
B. lacrimal gland
C. sublingual gland
D. thyroid gland
E. submandibular gland
2.The vagus nerves
A. are visceral motor nevers
B. contain the preganglionic fibers of parasympathic nerve
C. attached to the medulla oblongata
D.form anterior and posterior vagual trunk at esophageal hiatus where they leave the thorax
and pass into the abdominal cavity
E. supply all of visceral organs in the thoracic, abdominal and pelvic cavities
Ⅲ. Answer the following questions
1. Write out the nerves which distribute the tongue and their functions.
2. Write out the nerves which distribute the muscles which move the eyeball and coordinate
the pupil.
3. Write the fiber components, respective origins and distribution of the oculomotor nerve
The Visceral Nervous System
Learning Objectives
You should:

掌握内脏神经的区分和分布。

内脏运动神经:：掌握内脏运动神经与躯体运动神经的主要区别。掌握节前神经元、节
前纤维、节后神经元节及后纤维的概念。

交感神经

掌握交感神经的低级中枢部位。掌握交感干的位置与组成、主要椎前节的位
置。

了解灰、白交通支的概念、节前纤维和节后纤维的走行规律。

了解交感神经的分布概况。
86


颈部：了解颈上、中、下神经节的位置及节后纤维的分布概况。

胸部：掌握内脏大神经、内脏小神经的起源、纤维联系及分布概况。

腰部：掌握腰内脏神经的起源、纤维联系。了解节后纤维的分布概况。

盆部：了解节后纤维的分布概况。
副交感神经

掌握副交感神经的低级中枢部位。

掌握动眼神经内副交感节前纤维的起始、交换神经元的部位和节后纤维的分
布概况。

掌握面神经、舌咽神经内副交感节前纤维的起始、交换神经元的部位和节后
纤维的分布概况。


掌握迷走神经内副交感节前纤维的起始与节后纤维的分布概况。

掌握盆内脏神经的分布概况。

掌握交感神经与副交感神经的主要区别。了解内脏神经对器官双重支配的概念。

了解主要内脏神经丛的位置及分布。
内脏感觉神经：了解内脏感觉神经传入途径及特点。了解牵涉痛的概念。
sympathetic part
Visceral motor nerves
Composition
(autonomic nervous system)
parasympathetic part
Visceral sensory nerves
Ⅰ. Visceral motor nerves
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Main differences between somatic motor and visceral motor nerves
Somatic
Visceral
Effectors
Skeletal muscles
Cardiac, smooth muscles and glands
Kind of fibers
One
Two: sympathetic and parasympathetic
From lower center
Single neuron
Two neurons: preganglionic neuron (fiber)
to effect require
Fibers
and postganglionic neuron (fiber)
Thick myelinated
Preganglionic: thin myelinated
postganglionic: unmyelinated
Distributive form
Nerve trunk
Nerve plexuses
Control
Voluntary
Involuntary (unconsciousness )
(consciousness)
A. Sympathetic part
1. Lower center: located in lateral gray horn of spinal cord segments T1~L3
2. Sympathetic ganglia
a) Paravertebral ganglia: arranged on either side of vertebral column, consist of
19~22 of oval-shaped ganglia :
⑴Three cervical:
①Superior cervical ganglion: largest, situated in front
of transverse processes of C1~C3 vertebra
② Middle cervical ganglion: smallest, is at level of
transverse processes of C6 vertebra
③Inferior cervical ganglion: situated at level of C7
vertebra, and may be fused with first thoracic ganglion to form
cervicothoracic ganglion
⑵10~12 thoracic
⑶4 lumbar
⑷2~3 sacral
⑸Ganglion impar: unpaired on the anterior face of coccyx
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☆ Sympathetic trunk: formed by paravertebral ganglia and interganglionic branches, lie
on either side of vertebral column from base of skull to coccyx. The trunks of two side
unite in front of the coccyx at a small swelling, the ganglion impar
b) Prevertebral ganglia: lie anterior to vertebral column and near
the arteries for which they are named
⑴Celiac ganglion
⑵Aorticorenal ganglion
⑶Superior mesenteric ganglion
⑷Inferior mesenteric ganglion
3. Three fates of preganglionic fibers
Preganglionic fibers emerge from spinal cord with motor roots of corresponding spinal
nerves. They leave the spinal nerves by way of the white communicating branch and
enter the sympathetic trunks. Only the ganglia of T1 to L3 receive white communicating
branches, the white communicating branches have 15 pairs, lightly mylinated axons.
15 pairs white communicating branch
preganglionic fibers
sympathetic trunk
(only spinal levels T1~L3 have white communicating branch)
a) Relay in corresponding ganglion
b) Ascend or descend in sympathetic trunk and relay in higher or lower ganglia
c) Pass without synapse to a prevertebral ganglion for relay
⑴Greater and lesser splanchnic nerves
The greater splanchnic nerve formed by preganglionic fibers from
T5~T9 ganglia, and relay in celiac ganglion. The lesser splanchnic
nerve formed by preganglionic fibers from T10~T12 ganglia, and relay
in aorticorenal ganglion. The postganglionic fibers supply the liver,
spleen, kidney and alimentary tract as far as the left colic flexure.
greater splanchnic n.
〈○
preganglionic fibers from T5~T9 ganglia
celiac ganglion
lesser splanchnic n.
〈○
preganglionic fibers from T5~T9 ganglia
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aorticorenal ganglio
liver, spleen, kidney and alimentary tract as far as the left colic flexure
⑵Lumbar splanchnic nerve
lumbar splanchnic nerve
〈○
preganglionic fibers from L1~L4 ganglia
prevertebral ganglia
descending and sigmoid colon, rectum, pelvic viscera and lower limbs
4. Three fates of postganglionic fibers
a) Back to a spinal nerve along gray communicating branches ( 31 pairs ) to terminate
in blood vessels, arrectores pilorum and sweat glands of head, neck, trunk and limbs
b) The fibers from their networks around blood vessels passing to visceral end organs
c) Terminate directly in certain organs
Distribution of sympathetic nerve
Preganglionic fibers
Postganglionic fibers
T1~T5
Head, neck, upper limb and thoracic viscera
T5~T12
Abdominal viscera
L1~L3
Pelvic viscera and lower limb
A. Parasympathetic part
1. Lower center: located in four pairs parasympathetic nuclei in brain stem and in sacral
parasympathetic nucleus of spinal cord segments S2~S4
2. Parasympathetic ganglia: terminal ganglia are near or within the wall of a visceral
organ ( para-organ ganglia or intramural ganglia )
3. Cranial outflow (portion)
a)
Accessory nucleus of oculomotor nerve: preganglionic fibers from accessory
nucleus of oculomotor nerve travel by way of the oculomotor nerve to the ciliary
ganglion, postganglionic fibers from ciliary ganglion terminate in sphincter
pupillae and ciliary muscles of eye
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Ⅲ
accessory oculomotor nucleus○
sphincter pupillae and ciliary muscles
〈○
ciliary ganglion
b) Superior salivatory nucleus
pterygopalatine ganglion
Ⅶ
lacrimal gland
〈○
superior salivatory nucleus○
submandibular gland
〈○
submandibular ganglion
sublingual gland
c) Inferior salivatory nucleus
Ⅸ
inferior salivator nucleus○
parotid gland
〈○
otic ganglion
d) Dorsal nucleus of vagus nerve
Ⅹ
dorsal nucleus of vagus n. ○
heart, lungs, liver, spleen,
kidneys,alimentary tract
〈○
terminal ganglia
as far as left colic flexure
4. Sacral outflow (portion)
Preganglionic fibers from sacral parasympathetic nucleus leave spinal cord with anterior roots
of the spinal nerves S2~S4, then leave sacral nerves and form pelvic splanchnic nerve and travel
by way of sacral plexus to terminal ganglia in pelvic cavity,
postganglionic fibers terminate in
descending and sigmoid colon, rectum and pelvic viscera
anterior roots of S2~S4 sacral nerves
sacral parasympathetic nucleus ○
pelvic plexus
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pelvic splanchnic nerve
descending and sigmoid colon, rectum and pelvic viscera
〈○
terminal ganglia
B. Main differences between sympathetic and parasympathetic
Lower center
Sympathetic
Parasympathetic
Lateral gray horn of spinal
Four pairs parasympathetic
cord segments T1~L3
nuclei and sacral
parasympathetic nucleus
Ganglia
Paravertebral, prevertebral
Terminal
Preganglionic f.
Shorter
Longer
Postganglionic f.
Longer
Shorter
Pre: Postganglionic
1: many more
1: a few
Distributions
Throughout the body
Limited primarily to head and
viscera of thorax, abdomen,
and pelvis
Different action
Prepares for emergency
Conserve and restore body
situation (fight or flight)
energy (rest and relaxation)
C. Visceral plexuses
1. Cardiac
plexuses:
formed
by
sympathetic
and
parasympathetic components
a) Superficial , below aortic arch
b) Deep, anterior to bifurcation on trachea
2. Pulmonary plexus: anterior and posterior to lung roots
3. Celiac plexus: around roots of celiac trunk and superior
mesenteric arteries
4. Abdominal aortic plexus: is caudalward continuation of celiac plexus
5. Hypogastric plexus:
a) Superior hypogastric plexus: lies in front of L5 between common iliac ateries
b) Inferior hypogastric plexus (pelvic plexus): lie on each side of rectum
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Ⅱ.Visceral sensory nerves
Ⅱ.Visceral sensory nerves
Ⅸ, Ⅹ
nucleus of solitary tract
thalamus
〈○
cranial ganglia
〈○
enteroceptors
of viscera
cerebral cortex
hypothalamus
sympathetic nerve
〈○
pelvic splanchnic nerve
somatic motor neurons
〈○
spinal ganglia
posterior horn
effector
(reflex)
visceral motor neuclei
III. Referred pain
Sdudy questions
Ⅰ. Single choice questions (there five choices on each question, only one is correct, please
circle the correct answer):
1．The lower center of the sympathetic nerve is located in
A. gray matter in sacral segments S2~S4 of spinal cord
B. the Diencephalon
C. the cerebral cortex
D. lateral horn of gray matter in segments T1~L3 of spinal cord
E. the brain stem
2．Which structure is formed by preganglionic fibers of parasympathetic nerve
A. lumbar splanchnic nerve
B. pelvic splanchnic nerve
C. gray communicating branches
D. white communicating branches
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E. lesser splanchnic nerve
Ⅱ. Multiple choice questions (two to five choices are correct, please circle the correct answers):
1．which ganglia belong to the sympathetic ganglia
A. superior cervical ganglion
B. inferior cervical ganglion
C. paravertebral ganglia
D. prevertebral ganglia
E. geniculate ganglion
2．The lower center of the parasympathetic nerve contains
A. accessory oculomotor nucleus
B. superior salivatory nucleus
C. inferior salivertory nucleus
D. dorsal nucleus of vagus nerve
E. sacral parasympathetic nucleus in segments S2~S4 of spinal cord
Ⅲ. Answer the following questions
1．Give one example of each spinal, cranial, sympathetic and parasympathetic ganglia, and
write out their name, nature and fibrous connections.
2．Write out the origins, position of postganglia neuron and distributions of parasympathetic
fibers in vagus nerve
Part IV
The Endocrine System
Learning Objectives
You should:

了解内分泌腺的组成、结构特点及功能。(P466-467)

掌握垂体、甲状腺、甲状旁腺、肾上腺、松果体的形态和位置
endocrine glands: have no ducts, their secretions (hormone) release
Composition
directly into bloodstream to its target organ
endocrine tissue
Ⅰ.Thyroid gland — H-shape
A. Shape and position
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1. Left and right lobes: lie on either side of inferior part of larynx and superior part of
trachea, extend from middle of thyroid cartilage to level of sixth trachea cartilage
2. Isthmus: overlies 2nd to 4th tracheal cartilage
3. Pyramidal lobe: some times arises from isthmus
B. Fibrous capsule: a sheath of pretracheal fascia which is attached to arch of cricoid and
thyroid cartilages, hence, the thyroid gland moves with larynx during swallowing and
oscillates during speaking
C. Function: to produce thyroxin, regulating the rate of metabolism and growth of bony and
nervous system
Ⅱ. Parathyroid gland — yellowish-brown, ovoid bodies
A. Position
1. Two superior parathyroid glands: lie at junction of
superior and middle third of posterior border of thyroid
gland
2. Two inferior parathyroid glands: lie near the inferior
thyroid artery, close to the inferior poles of thyroid gland
B. Function: regulate calcium and phosphate balance and is therefore essential for life
Ⅲ. Suprarenal gland
A. Shape and position
1. Right is pyramidal in shape, left one semilunar in shape,
consisting of out cortex and inner medulla
2. Located retroperitoneally, superomedial to superior poles
of each kidney, enclose with the kidney by the renal fascia
B. Function: secretes adrenaline, noradrenaline and several steroid hormones
Ⅳ. Hypophysis
A. Shape and position
1. Pea-sized organ, attached by infundibulum to hypothalamus, lies in hypophysial
fossa
2. Consists of two parts: adenohypophysis and neurohypophysis
B. Relationship
1. Above－diaphragm sellae
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2. Anterosuperior－optic chiasma and optic nerve
3. Laterally－cavernous sinus
4. Below－sphenoid sinus
Ⅴ. Pineal body: locates in posterosuperior to thalamus, attached by stalk to posterior part of roof
of third ventricle
Ⅵ. Thymus:
A.
Position: located in superior mediastinum, posterior to sternum and between the lungs
B.
Function:
1. Secrets thymosin: to aid in maturation of T-cell
2. Secrets thymopoietin
Ⅶ. Pancreatic islet
testis
endocrine tissue
Ⅷ. Gonad
ovary
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