Name
Function
Origin
Olfactory
Nerve (I)
S: smell
Cerebrum
Optic
nerve (II)
S: vision
Cerebrum
Oculomotor
nerves (III)
Trochlear
Nerves (IV)
Trigeminal
Opthalmic
branch (V1)
Maxillary
branch (V2)
Mandibular
Branch (V3)
Abducens
Nerves (VI)
Facial
Nerves
(VII)
Vestibulocochlear
Nerves (VIII)
Glossopharyngeal
Nerves (IV)
Vagus
Nerves
(X)
M: 4 eye muscles
S: PA from 4 muscles
P: constrictor papillary
muscles (pupil) & ciliary
muscles (lens thicken)
M: Superior Oblique Muscle
S: PA from SOM
S: upper eyelid, eye surface,
lacrimal glands, nose, scalp &
forehead
S: Upper teeth, gum, lip,
palate, skin of cheek,
& lower eyelid
M: mastication
S: lower teeth, gum, lip, skin
of jaw, & part of scalp
M: Lateral Rectus Muscles
S: PA from LRM
M: facial expression
S: Taste from anterior 2/3
P: parasympathetic of
salivary glands
(submandibular & sublingual)
Ventral
midbrain
(near its
junction
with pons)
Dorsal
midbrain
S:
Cochlear: sound
Vestibular: equilibrium
Ponsmedulla
border
M: pharynx for swallowing
S: taste from posterior 1/3
Tonsils, Eustachian tubes
Carotid arteries (B.P., chem.)
P: parotid salivary glands
M: pharynx & larynx
S: posterior tongue, pharynx,
thoracic, & abdominal viscera
P: heart, lungs, smooth
muscles of pharynx, larynx,
thoracic, & abdominal viscera
Medial
Pons
Tract
Olfactory nerves->olfactory bulb->
olfactory tract-> mammillary body->
Primary olfactory Cortex
Retina-> Optic nerves-> optic canal of the
sphenoid bone -> optic chiasma (just
above the pituitary gland) [Decussation] > optic tracts-> lateral geniculate bodies
of thalamus-> visual cortex of the
occipital lobe
Fissure
Cribriform plate
of the ethmoid
bone
Optic canal of
sphenoid bone
[instead of lateral geniculate bodies, it
may go to superior Colliculi]
Midbrain ->
Superior orbital fissure ->
4 eye muscles
(inferior oblique, superior rectus,
inferior rectus, medial rectus)
Midbrain->superior orbital fissure->
Eye muscles
Superior orbital
fissure
Pon->trigeminal ganglion->superior
orbital fissure->(supraorbital foramen)
Superior orbital
fissure
Pon->trigeminal ganglion->Foramen
rotundum->(infraorbital foramen)
Foramen
rotundum
Superior orbital
fissure
Pon->trigeminal ganglion->Foramen
ovale->(mandibular foramen
& mental foramen)
Pon -> superior Orbital fissure -> eye
muscle
Pon -> internal acoustic meatus ->
geniculate ganglion ->
stylomastoid foramen ->
face muscles (Temporal, Zygomatic,
Buccal, Mandibular, Cervical)
Cochlea or semicircular canals ->
Vestibular ganglia -> separated ->
Internal acoustic meatus -> VIII ->
Primary auditory cortex of Temporal lobe
[VIII -> Inferior Colliculi]
Internal acoustic
meatus
(stylomastoid
foramen)
Lateral
Medulla
Medulla -> jugular foramen -> throat
Jugular foramen
Lateral
medulla
Medulla -> Jugular foramen -> neck &
heart, lung, abdominal viscera
Jugular foramen
Inferior
Pons
Pons
(lateral to
abducens)
Foramen ovale
Superior orbital
fissure
Internal acoustic
meatus
Spinal
Accessory
Nerves(XI)
Hypoglossal
nerves (XII)
M: shoulder, neck
Lateral
Spinal root -> foramen magnum ->
(sternocleidomastoid,
medulla
emerges with cranial root -> jugular
trapezius) pharynx, larynx
(C1-C5,
foramen -> joins with Vagus nerve->
S: PA from same muscles
too)
accessory nerve
M: in & extrinsic tongue
Medial
muscles (move the tongue)
Medulla -> hypoglossal canal -> tongue
Medulla
S: PA from the same muscles
M=Motor, S=Sensory, P=Parasympathetic, PA=proprioceptive Afferent
LR6SO4O3
Lateral Rectus muscle = Abducens (VI) nerve
Superior Oblique muscle = Trochlear (IV) nerve
Other 4 muscles = Oculomotor (III) nerve
Origin
2 cerebrums + 2 midbrains + 3pons + 5 medullas
2 cerebrums + 2 midbrains + 3pons + 1 pons-medulla + 4 medullas
Fissure [(1, 1), (4, 2, 2), (3, 1)]
= 1 CP of EB, 1 OC of SB, 4 SOFs (2Foramens=V2, V3), 2 IAMs, 3 JF, 1 HC
Sensory [1, 2, 1, 2, 8]
= 1, 2, 5(V1, V2), 8
Parasympathetic
3+7=10, 9
Motor
Rest of all: 4, 5(V3), 6, 11, 12
Jugular foramen
(foramen
magnum)
Hypoglossal canal
Name
Precentral gyrus
(primary motor
cortex)
Premotor area
Broca’s area
Prefrontal lobe
Post central gyrus
(primary
Somatosensory
cortex)
Somatosensory
association area
Primary Auditory
Cortex
Auditory
association area
Wernicke’s area
Primary Olfactory
cortex
Visual cortex
Visual association
area
Limbic
Insula
Function
Location
Skeletal muscle movements
Contralateral innervation
Frontal
Controls learned, repetitious motor skills
Movement of muscles involved in speech
(lips, tongue, throat)
Emotion & Logical Brain
Receives input from sensory receptors in
skin muscles
Identify where body region input is from
(proprioceptors)
Integrates and analyzes sensory input
Evaluates size, texture, relationship
Receives info from organ of Corti in
cochlear in inner ear for sound
Uses memories of sounds for
sound recognition
Understanding written and spoken
language
Sounding out unfamiliar words
Frontal
Smell from Olfactory bulb
Receives input from retina
Surrounds visual cortex
Interprets visual inputs
Uses past experiences
Visual recognition
Emotional brain
(related with smell)
Memory processing
Extensive link to lower and higher brain
areas
Visceral responses (consciously aware)
May be involved with
autonomic & somatic activities
Frontal
Frontal
Parietal
Parietal
Superior temporal
gyrus
Temporal
Posterior
Temporal
Deep to inferior to
temporal
Occipital
(calcarine sulcus)
Occipital
Limbic
Deep to lateral
sulcus
Hypothalamus
Cingulate
gyrus(emotion)
Hippocampus
Amygdala
(memory)
Name
Thalamus
Hypothalamus
Infundibulum
Pituitary gland
Mammilary body
Supraoptic nucleus
Paraventricular
nucleus
Epithalamus
(pineal body)
Basal nuclei
Cerebral Peduncle
Midbrain
Superior Colliculi
Inferior Colliculi
Pons
Medulla Oblongata
Description & Function
Contains many nuclei
Projects fibers to & from the cortex
Sorts and edits info for the cortex
Directs info to proper cortical region
Initiates physical expression of emotions (linked to
the limbic system)
Autonomic center (B.P, D.R, R.R)
Connection of Hypothalamus & pituitary
Neuroendocrine gland
regulation of gonads, thyroid, adrenal cortex,
lactation, and water balance
Relay station for olfactory pathways
Contains neurons that produce ADH
(antidiuretic hormone)
Contains neurons that produce oxytocin
(stimulate uterine during labor
& milk ejection for nursing)
Secretes melatonin
Regulate sleep/wake cycles
influenced by light (intensity & length)
Project messages through thalamus(memory) to
premotor & prefrontal areas
Monitors & regulate movements from motor cortex
(intensity of movements)
(inhibit unnecessary movements)
Stalks (cerebellum to the brainstem)
Containing Corticospinal tract
Cerebral peduncles, cerebral aqueduct, corpora
quadrigemina, substantia nigra
Visual reflex centers
Coordinate head and eye movements
Act in reflexive responses to sound
Mostly contains the tracts
Autonomic relay center
B.P., R.R., Hiccup, vomit, sallow, cough
Nucleus Cuneatus & Gracilis
Olivary Nuclei (stretch of muscles & joint)
Location
Related
Diencephalon
(makes up 80% of
Diencephalon)
Intermediatemass
Diencephalon
Thirst, food, temp,
feeling, sexual
behavior
Diencephalon
Diencephalon
Diencephalon
Diencephalon
(hypothalamus)
Diencephalon
(hypothalamus)
Diencephalon
Part of parietal
and temporal
Caudate -nucleus
Putamen
Globus pallidus
Midbrain
Bet. diencephalon
& Pon
III & IV
Midbrain
Midbrain
Under Midbrain
Under Pon
V, VI, VII
Cardio center
Respi Center
VIII, IX, X, XI, XII
Corticospinal
tracts
Pyramids
Anterior bulges containing white matter
Decussation of pyramids
Medulla
oblongata
Reticular
Formation
Filter for flood of sensory inputs
Disregard 99% of all sensory stimuli
RAS (govern arousal of the brain)
Central core of
the medulla
oblongata, pons,
and midbrain
Reticulospinaltract
Hypo Thalamus
Cerebellum
Spinal cord
Cerebellum
2 hemi. Separated by the falx cerebelli
Vermis: worm-like structure between
the 2 hemispheres Processes info
Sends output regarding timing
& coordination of skeletal muscle contraction
Makes movements smooth & coordinated
Behind pons and
medulla
Arbor vitae
Folia & Fissures
Superior Cerebellar
Peduncle
Middle Cerebellar
Peduncle
Inferior Cerebellar
peduncle
…………………………….
Lateral ventricles
(1st and 2nd)
3rd ventricle
4th ventricle
Filum Terminale
Conus Medullaris
Cauda Equina
Carries axons between
midbrain & cerebellum
Carries axons between
the pons and cerebellum
Carries axons between
the medulla and cerebellum
…………………………………………………………….
Midbrain
Pons
Medulla
………………………….
………………………
Anterior, inferior and posterior horns
Within
diencephalon
Dorsal to pons
and medulla
Opens into central canal of spinal cord and
subarachnoid space around brain
Extension of pia mater attaching the cord to the
coccyx
Caudal end of spinal cord
Nerves from the lower cord running inferior before
exiting the vertebrae
B.P.=Blood Pressure, D.R.=Digestive Rate, R.R.=Respiration Rate
Cerebral aqueduct
Name
Description
Epidural space
Space between bone and the dura
Double-layered
One layer is Fused to skull (periosteum)
The other deeper one is the true external
covering brain and extends to Dural sheath of
the spinal cord
collect venous blood from the brain and direct
it into the internal jugular veins of the neck
Space below dura and above arachnoid layer
Web-like extensions down to pia mater
Filled with CSF
Numerous blood vessels
Dura mater
Dural space
Subdural space
Arachnoid mater
Subarachnoid
space
Arachnoid villi
(granulation)
Pia mater
Hydrocephalus
Meningitis
Encephalitis
TIA (Transient
ischemic Attacks)
Alzheimer’s
Disease
Parkinson’s
Disease
Huntington’s
Disease
Related structures
Dural Septa
Falx Cerebri
Tentorium cerebelli
Falx Cerebelli
4th ventricle
Drain CSF into Dural sinuses
Adheres to brain and spinal cord
Follows folds of brain
Very vascular
Buildup of CSF due to blockage or obstruction
Exerts pressure on the brain
Can cause permanent brain damage
Inflammation of the meninges caused by a viral
or bacterial infection
May spread to nervous tissue of CNS
Brain tissue inflammation
Fatal 50% of the time
Temporary blood deprivation(5~50min)=>
numbness, paralysis, impaired speech
Usually warning of an impending,
more serious stroke
Progressive degeneration of brain function
Deficit of Ach
Memory loss, shortened attention span,
disorientation, possible language loss
Degeneration of dopamine releasing neurons
Basal ganglia become deprived of dopamine
Persistent tremors, forward bent posture when
walking and shuffling gait
Hereditary
Massive degeneration of the basal ganglia &
eventually the cerebral cortex
Causes spastic, abrupt, jerky movements
Mental deterioration & death
Filum terminale: Small extension of pia
It fastens the spinal cord down to the
coccyx bone
Arachnoid villi
Dural sinuses
Tumor
Name
Pathway
Function
Contralateral
/Decussation
Muscle spindle (proprioceptor) ->
[Axon of 1st order neuron]
Posterior: X
Dorsal horn of gray matter->
Spinocerebellar
Posterior spinocerebellar tract
[axons of 2nd order neurons]–>
Medulla oblongata->
Impulses from trunk &
lower limb
subconscious
proprioceptors
(Merkel’s discs)
Pons->
Anterior: X
Contains crossed
fibers that cross
back to the
opposite side in
the pons
Cerebellum
Touch receptor ->
Fasciculus Gracilis or Cuneatus
[axon of 1st sensory neuron] ->
Fasciculus
Gracilis
&
Cuneatus
Nucleus Gracilis or Cuneatus
(medulla oblongata)->
Medial lemniscal tract
[axons of 2nd order neurons]->
Pons->
General sensory
receptors of
skin & proprioceptors
(discriminative touch,
pressure, position)
Cuneatus: upper limb,
upper trunk, and neck
C1~T6
Midbrain->
Thalamus
[axons of 3rd order neurons]->
Somatosensory cortex (Cerebrum)
Gracilis: lower limb,
inferior body trunk
Cross to opposite
side at medulla
oblongata
Name
Pathway
Function
Contralateral
/Decussation
Temperature or pain receptors
[axon of 1st sensory neuron] ->
Dorsal horn of gray matter->
Medulla oblongata->
Spinothalamic
pathway
Lateral spinothalamic tract
[axons of 2nd order neurons]->
Lateral:
Pain (skin, not by dead
cell)& temperature
Anterior:
crude touch (Pacinian
& Ruffini’s) & pressure
Pons->
Midbrain->
Cross to opposite
side before
ascending (goes
from dorsal horn to
ventral horn and
ascend)
Thalamus
[axons of 3rd order neurons] ->
Somatosensory cortex (Cerebrum)
Primary motor area
(cerebral cortex)
[Upper motor neurons] ->
Internal capsule ->
Cerebral peduncle (Midbrain) ->
Lateral: decussate
in pyramids of
medulla
Pons->
Corticospinal
Medulla oblongata->
skeletal muscles
Pyramids->
Decussation of pyramid (Lateral)->
Lateral Corticospinal tract->
Skeletal muscle
[lower motor neurons]
Pg. 476
Anterior:
Cross over at spinal
cord
Name
Pathway
Quadriceps tendon stretched->
Monosynaptic
reflexes
(patellar reflex
Stretch reflex)
Muscle spindles send impulse
(muscle stretching)->
Spinal cord ->
Motor neuron ->
Quadriceps muscle contracts
Pain receptors ->
Spinal cord ->
Polysynaptic
reflexes
Association neuron ->
(Withdrawal reflex
Crossed extensor
reflex)
Motor neurons
(to muscles for contraction)->
Integration ->
Flexors contract ->
Extensors extend for balance
Name
Exteroceptors
[Free 4 friends
MMPR)
Description & Function
Near the body surface
Pick up messages
from the external environment
Pick up Tough, Pressure, Pain,
Temperature, Special senses
Interoceptors
(Visceroreceptors)
[Free pacinain]
Detect stimuli originating from within
the body
Pain, discomfort, stretching tissue,
temperature
Proprioceptors
[Free Pat & Ruff
have gorgeous
muscle]
Respond to internal stimuli
In muscles, tendons, ligaments, joints
Monitor degree of stretch
Mechanoreceptors
[Mark, Mason &
Pat have gorgeous
muscle]
Send impulses when tissues deformed
by mechanical forces
Touch, pressure, vibrations, itching
Chemoreceptors
Detect dissolved chemicals
Photoreceptors
thermoreceptors
Detect changes in light
Detect changes in temperature
Detect pain or potentially damaging
stimuli
It is stimulated by noxious stimuli
Damaged body tissues release
chemicals bind to pain receptors
(ATP released from injured cells may
stimulate some pain receptors)
Visceral pain and somatic pain follow
the same neural pathway, visceral pain
may be perceived as somatic pain
Nociceptors
Pain receptors
(free nerve
endings)
Referred pain
Examples
Free nerve endings: Pain, temp., and
pressure
Merkel’s Discs: In deep dermis, Light touch
Meissner’s Corpuscles:
In dermal papillae of hairless skin
(lips, nipples, fingertips)
Light pressure & discriminative touch
Pacinian corpuscles: In hypodermis of skin,
periosteal, ligaments, joint capsules, fingers,
soles of feet, external genitalia & nipples
deep pressure & stretch
Ruffini’s corpuscles: deep dermis,
hypodermis & joint capsules, like Pacinian
Free nerve endings
Pacinian corpuscles
Free nerve endings
Pacinain’s corpuscles
Ruffini’s corpuscles
Golgi tendon organs
Muscle spindles
Merke’s discs
Meissner’s corpuscles
Pacinian corpuscles
Golgi tendon organs
Muscle spindles
Olfactory receptors
Taste receptors
Retina of the eye
Free nerve endings
Free nerve endings
All receptor types may function in this
Somatic Pain: from skin, muscle, joints
Visceral Pain: From receptors in organs in the
body cavities, results from stretching tissue,
muscle spasms, or chemicals
Cheek: Heart
R Neck: liver L Neck: lungs & diaphragm
Center: liver, stomach
Draw these tables as many as you can.
To find the root of branches, trace back from cords to Roots.
Root of Muculocutaneous (C5~C7). Median (C5~T1), Ulnar (C8, T1), Radial (C5~T1), Axillary (C5, C6 exception)
Illiohypogastric
Illioinguinal
L1
Genitofemoral
L2
Lateral femoral cutaneous
L3
Femoral,Obturator
(L2~L4)
Lumbosacral
L4
L5
Common fibular
S1
Tibial
Sciatic
S2
S3
S4
Superior gluteal
Inferior gluteal
Posterior femoral cutaneous
Pudendal