Divisions of Nervous System by Location
CNS and PNS
CNS
brain and spinal cord (motor & sensory components)
PNS
31 pairs of spinal nerves (motor and sensory components) and 12 cranial nerves (motor or sensory or both)
Divisions of Nervous System by Function
somatic (voluntary & reflex), visceral (autonomic, involuntary), and enteric(nervous tissue within intestinal tract)
Visceral components
parasympathetic(rest and digest) and sympathetic (fight or flight)
enteric nervous tissue
nervous tissue within intestinal tract, can act independently of CNS or ANS
Divisions of nervous system by development
somatic, visceral, and branchial
Somatic Division
skeletal muscle efferent and general sensory afferent
Visceral Division
smooth muscle efferent and general visceral afferent
Branchial Division
skeletal muscles of head and neck derived from branchial arches
Motor Nurons Efferent are
multipolar
Afferent Sensory neurons are
unipolar
Somatic Structures derive from
Embryonic paraxial somites (ex skeletal muscles)
Visceral Structure include
gut, heart, lungs, glands, genitourinary systems & glands
Branchial Structures develop from
branchial arches of the embryo
Things that develop from somatic cells
eye, ear, nerve cord, notochord, trunk wall, tail, and skeletal muscle
Things that develop from visceral portion
jaws, pharynx, gut, and associated parts including branchial mm
What nerve innervates the 1st branchial arch
trigeminal N (CNV)
what nerve innervates the 2nd arch
facial N (CNVII)
what nerve innervates 3rd arch
glossopharyngeal N (CNIX)
what nerve innervates the 4th and 6th arch
Vagus N (CNX)
What nerve innervates the 5th arch?
No nerve, no arch
What develops from arch 1?
malleus and incus
What develops from arch 2?
stapes and stylohyoid ligament
What develops from arch 3?
hyoid body
What develops from arch 4?
thyroid cartilage and cricoid cartilage
General Visceral Efferent Motor Nerves (GVE)
autonomic fibers to smooth and cardiac muscle, parasympathetic for cranial and sacral nerves, sympathetic for spinal nerves in thoracic and lumbar regions
General Somatic Efferent motor nerves (GSE)
innervate skeletal muscles derived from somites
T/F all spinal nerves have GVE and GSE Fibers
True
Special Visceral or Branchial Efferent motor nerves (SVE or BE)
innervate striated muscles derived from branchial arches
Where are SVE or BE branches found?
In cranial nerves V, VII, IX, X, XI
General Somatic Afferent sensory nerves (GSA)
touch, pain, heat loss/gain, & proprioception from the body
General visceral afferent sensory nerves (GVA)
touch, pain, and proprioception from viscera
T/F all spinal nerves have GSA and GVA fibers
True
Special Visceral Afferent nerves (SVA)
olfaction and taste
where are special visceral afferent nerves found?
cranial nerves I, VII, IX, and X
Special Somatic Afferent Nerves
vision and hearing/equilibrium
where are special somatic afferent nerves found?
cranial nerves II and VIII
autonomic nervous system
control of involuntary/subconscious regulation of visceral effector organs: smooth muscle, cardiac muscle, glands
How many neurons are required for a motor response
2, pre and post ganglionic fibers
Sympathetic Division of Autonomic Nervous System (SANS)
fight or flight response
What nervous outflow to paravertebral ganglia
thoracolumbar (T1-L2)
Parasympathetic Division of Autonomic Nervous System (PANS)
rest and digest function
Craniosacral outflow of PANS
CNIII, VII, IX, X to cranial autonomic ganglia and S2-4 outflow to prevertebral ganglia
Organization of ANS
brain, spinal cord, cranial nerves, spinal nerves, hypothalamus, medulla
hypothalamus
coordinates and maintains homeostasis, regulates and integrates visceral activity like heart rate, blood flow, glucose levels, gland secretion, GI motility
medulla
reflex center: cough, vomit, sneeze, respiration, hiccup, swallow
Sympathetic ganglia of head and neck
superior cervical ganglion
Parasympathetic 4 cranial ganglion
ciliary, pterygopalatine, submandibular, and otic
CNIII ganglion
Ciliary ganglion
CN VII ganglions
pterygopalatine ganglion and submandibular ganglion
CN IX ganglion
Otic ganglion
CN I skull foramina
cribiform plate
CN I nuclei
mitral cells of olfactory bulb
CN I function and distribution
special sensory smell, there are thousands of olfactory nn passing through the cribiform plate to the bulb
CN II skull foramina
optic canal
CN II nuclei
retinal ganglion cells
CN II function and distribution
special sensory vision, deep in retina about 1.5 million ganglia cells transmit sensory info through the optic N
CN III skull formina
superior orbital fissure
CN III nuclei
oculomotor and endinger-westphal
CN III action, occulomotor nuclei
somatic motor to most extrinsic eyeball muscles
CNIII action, edinger-westphal nucleus
visceral motor (parasympathetic and sympathetic) to iris and ciliary muscles of eye
CNIV skull foramina
supraorbital fissure
CN IV Nuclei
Trochlear
CN IV function
somatic motor to superior oblique
CN V1 skull foramina
supraorbital fissure
CN V2 skull foramina
foramen rotundum
CN V3 skull foramina
foramen ovale
CN V nuclei
trigeminal nucleus and masticator nucleus
Action of trigeminal nucleus
general sensory from face, scalp, mucosa of oral and nasal cavities and pharynx
Action of masticator nucleus
branchial motor to muscles of mastication, anterior digastric, mylohyoid, tensor tympani, tensor veli palatini
CN VI foramina
supraorbital fissure
CN VI nuclei
abducens
CN VI action
somatic motor to lateral rectus
CN VII foramina
in auditory meatus, facial canal, stylomastoid foramen
CN VII nuclei
gustatory, trigeminal, facial nucleus, and superior salivatory
Gustatory nuclei action
special sensory taste of ant 2/3 of tongue
Trigeminal Nuclei action of VII
general sensory to external auditory meatus and ear
Facial Nucleus action
branchial motor to facial expressions muscle, stylohyoid, digastric posterior belly, stapedius
Superior Salivatory nucleus action
parasympathetic fibers to head gland EXCEPT parotid
CN VIII skull foramina
internal auditory meatus
CN VIII nuclei
cochlear and vestibular
Cochlear nuclei action
special sense hearing
Vestibular nuclei action
special sensory equilibrium
CNIX skull foramina
jugular foramen
CN IX nuclei
gustatory, trigeminal, solitary, ambiguous, inferior salivatory
gustatory nuclei of CN IX
special sensory taste to post 1/3 of tongue
Trigeminal nuclei of CNIX
general sensory to post 1/3 of tongue, pharynx and middle ear
Solitary Nucleus action
visceral sensory of carotid body and sinus
ambiguous nuclei action
branchial motor to stylopharyngeus
Inferior salivatory nuclei action
visceral motor to parotid gland
CN X skull foramina
jugular foramen
CNX nuclei
ambiguous, gustatory, solitary, and dorsal vagal
Ambiguous nuclei of CN X
branchial motor to larynx, pharynx, and soft palate
Gustatory nucleus action of CN X
special sensory taste from laryngeal inlet
Solitary nucleus action of CNX
visceral sensory from gut, lungs, heart
Dorsal vagal nuclei
visceral motor to thorax/gut (parasympathetic)
CN XI skull foramina
jugular foramen
CN XI nuclei
accessory
CN XI action
branchial motor to trapezius and SCM