Cardiac

Smooth

Skeletal

related to organ muscles:  kidneys, bladder, gastrointestinal and reproductive

involuntary - cardiac and smooth muscles and glands (Autonomic Nervous System - ANS)

voluntary (Somatic Nervous System)

sensory nerve – contain sensory neurons

vision, smell, touch (tactile representation, temperature)

motor nerve  - contain motor neurons

 Motor information to muscles and glands

# of pairs of spinal nerves

31

extend from the spinal cord

12

extend from the brain

PNS consists of spinal and cranial nerves and the peripheral – ganglia - areas of the ANS that they innervate (provide function to)

8

Head, neck, diaphragm, arms, hands

12

chest and abdominal muscles

5

leg muscles

5

Digestion, bladder, reproductive muscles

1

tailbone

 network

- complex areas where branches of adjacent spinal nerves meet to innervate serveral muscles at one time.  

•last 4 cervical and first thoracic nerves, arm, forearm and hand

•first 4 lumbar nerves, lower limbs

•4th and 5th lumbar nerves and the first four sacral nerves

(depending on sensory input)

extends from the brain (through the foramen magnum) and through the spinal column

cell bodies outside of central nervous system (dorsal root ganglion – a swelling on the dorsal root)

provide protection between spinal cord and vertebrae

Dorsal

Posterior

Back

Ventral

Anterior

Front

cluster of cell bodies in the PNS

cluster of cell bodies in the CNS (gray matter)

bundle of axons (nerve fibers) in the CNS; smaller than a tract (arcuate fasciculus)

Pillar of nerve fibers in spinal cord

a bundle of nerve fibers forming one of the main tracts of white matter in the spinal cord.

sensory

Dorsal root ganglion – origination of sensory neurons

motor

Ventral horns – origination of motor neurons

union of sensory and motor fibers

branches from each root – extend after formation of spinal nerve and are mixed with motor and sensory fibers

 continuation of the ventricular system; filled with cerebrospinal fluid

Gray Matter (clusters of cell bodies)

•Dorsal/Posterior horns

 •Ventral/Anterior horns

 •Lateral horns 

White Matter – organized in columns of white matter tracts (myelinated axons/fibers)

•Dorsal/Posterior funiculus

•Ventral/Anterior funiculus

•Lateral funiculus

Efferent processes conduct impulses from the brain and spinal cord to skeletal muscles for voluntary motor movement

Efferent processes conduct impulses from the brain and spinal cord to visceral areas (cardiac muscles, smooth muscles and glands) for involuntary motor movement

Fight/Flight = Activates

•Thoracic and lumbar regions

 •Ganglia close to the spinal cord in a chain 

 •Long postganglionic fibers

•Involves cranial nerves and spinal nerves from sacral regions

•Ganglia close to target organs

•Short postganglionic fibers

A band or region of skin supplied by a single sensory nerve root.

sense of body position in time and space

temperature/heat

visual – light

1) CNI: Olfactory Nerve

2) CNII: Optic Nerve

3) CNIII: Oculomotor Nerve

4) CNIV: Trochlear Nerve

5) CNV: Trigeminal Nerve

6) CNVI: Abducens Nerve

7) CNVII: Facial Nerve

8) CNVIII: Vestibulocochlear Nerve

9) CNIX: Glossopharyngeal Nerve

10) CNX: Vagus Nerve

11) CNXI: Accessory Nerve

12) CNXII: Hypoglossal Nerve

General (G) or Special (S)

General – distributed throughout the body

Special – restricted area of the body

Visceral (V) or Somatic (S)

- Visceral – ANS

- Somatic

Afferent (A) or Efferent (E)

Afferent – Sensory

Efferent – Motor

GSA: General Somatic Afferent

GSE: General Somatic Efferent

GVA: General Visceral Afferent

GVE: General Visceral Efferent

SSA: Special Somatic Afferent

SVA: Special Visceral Afferent

SVE: Special Visceral Efferent

Sensations of touch, pain, temperature (from skeletal muscles)

Cranial Nerves: V, VII, IX, X

Motor to skeletal muscles

Cranial Nerves: III, IV, VI, XII

Sensory information from organs

Cranial Nerves: VII, IX, X

Refers to parasympathetic supply

Motor to cardiac and smooth muscle, glands

Cranial Nerves: III, VII, IX, X

Special senses in vision and hearing

Cranial Nerves: II, VIII

Special senses from organs – taste and smell

Cranial Nerves: I, VII, IX, X

Specialized motor to areas of pharynx, larynx and middle ear, mouth, jaw area

Cranial Nerves: V, VII, IX, X

CNIII: Oculomotor Nerve

CNVII: Facial Nerve

CNIX: Glossopharangyeal Nerve

CNX: Vagus Nerve

Sense of Smell

CNI: Olfactory Nerve

• Shortest cranial nerve
• Sensory Only
• SVA – Special Visceral Afferent Special sense of smell
• One of two (CNII) that do not originate in part of the brain stem
• Originates in the olfactory mucosa in the upper part of the nasal cavity - ethmoid bone)
• Fibers enter the olfactory bulb via the olfactory tract – carry sensory information from receptors to other areas
• Primary olfactory cortex sends information to many other parts of the brain (including amygdala, hipppocampus – memory)
• Only sense that is not processed through the thalamus

CNII: Optic Nerve

CNIII: Oculomotor Nerve

CNIV: Trochlear Nerve

CNVI: Abducens Nerve

• Sensory only
• SSA: Sensory Somatic Afferent
• Special input from retina
• Originates in the eyeball One of two (CNI) that do not originate in part of the brain stem

• Areas of the retina
• Medial/nasal – inner, cross
• Lateral – Outer, dont cross
• Optic Chiasm (“crossing”)
• optic nerves from each eye meet
• Point of decussation for medial fibers only
• Left and right optic tracts
• Carry ipsilateral and contralateral innervations in visual system
• Travel through the thalamus to the visual cortex (occipital lobes)

• Motor only
• GSE (General Somatic Efferent)
• Motor to extraocular muscles
• GVE (General Visceral Efferent)
• Parasympathetic motor functions
• Has parasympathetic supply
• Originates in anterior of midbrain

• Two branches:
• Superior Branch
• Raises eyeball and upper eyelid
• Inferior Branch (Parasympathetic Supply)
• Innervates pupils – constricts to reduce amount of light Innervates ciliary muscles – contract to adapt to short range vision
• Raises and lowers eyeball
• Lateral Adduction (toward nose) and Abduction(away from nose) of eyeball
• Rotates eyeball

• Motor only
• GSE: General somatic efferent
• General motor to extraocular muscles
• Originates in the posterior aspect of the midbrain
• Innervates a single muscle – superior oblique muscle
• Muscle above the eye
• Allows one to look down and inward

• Motor only
• GSE: General Somatic Efferent
• General motor to extraocular muscles
• Originates at the junction of the pons and medulla
• Innervates a single muscle – lateral rectus
• Allows abduction of eyeball (ability to look away from the nose/midline)

CNV: Trigeminal Nerve

CNVII: Facial Nerve

CNVIII: Vestibulocochlear (Acoustic-Vestibular)

CNIX: Glossopharyngeal Nerve

CNX: Vagus Nerve

CNXI: (Spinal) Accessory Nerve

CNXII: Hypoglossal Nerve

• Sensory and Motor (Mixed)
• GSA – General somatic afferent
• general sensation from face and mouth
• SVE – Special Visceral Efferent
• Specialized motor to mandible and surrounding areas
• Origination: brainstem
• Sensory nuclei
• Mesenephalic (midbrain)
• Principal sensory
• Spinal nuclei
• Motor nucleus
• Extends from midbrain to medulla

• Divisions of Fibers
• Ophthalmic Nerve (V1)
• Sensory only (GSA)
• Maxillary Nerve (V2)
• Sensory only (GSA)
• Mandibular Nerve (V3)
• Sensory (GSA)
• Motor (SVE)

• Three terminal branches
• Frontal
• Nasociliary
• Lacrimal
• Innervations:
• Forehead and scalp
• Superior and medial areas of sinuses
• Upper eyelid
• Cornea
• Middle area of the nose

• 14 terminal branches
• Zygomatic – travels along zygomatic branches of facial nerve (CNVII)
• Innervations:
• Lower eyelid
• Cheeks and medial sinus areas
• Nasal cavity and lateral nose
• Upper lip and teeth
• Superior palate

Mandibular Nerve (V3)

Sensory

• Sensory
• Buccal nerve
• Inferior alveolar nerve
• Auricotemporal nerve
• Lingual nerve
• Sensory Innervations:
• Anterior two-thirds of tongue
• Mandible (jaw)
• Lower teeth and lip
• Part of cheek and external ear

• Motor Branches of Mandibular Nerve:
• Masseter nerve
• Deep temporal nerves
• Motor Innervations:
• Muscles of mastication
• Muscles of the palate
• Mylohyoid and Digastric muscles
• Tensor Tympana

Masseter

Temporalis

Lateral Pterygoid

Medial Pterygoid

Swallowing

Breathing:

Gag reflex:

• Mixed: Sensory and Motor
• Several Modality Classifications
• GSA, GVA, SVA, SVE, GVE (parasympathetic)
• Originates in the pons
• Intracranial and Extracranial Branches
• Specific set of branchial motor branches that supply muscles of facial expression

• GSA: General Somatic Afferent Sensory
• – skin of the posterior ear
• GVA – General Visceral Afferent
• - Sensory from soft palate and parts of the nasal cavity
• SVA – Special Visceral Afferent
• - Special sense of taste for the anterior 2/3 of tongue 
• SVE – Special Visceral Efferent
• - Motor to muscles of facial expression
• - Ear and neck muscles
• GVE – General Visceral Efferent (Parasympathetic)
• - Motor to sublingual and submandibular(salivary), and lacrimal glands tears)

• Inside the cranial cavity
• Greater petrosal nerve (GVE)
• Parasympathetic fibers to many glands including lacrimal and all salivary glands except the parotid glands (IX)
• Nerve to stapedius muscle (SVE)
• Special motor fibers to middle ear
• Chorda tympani (SVA & GVE)
• (SVA) Special sensation of taste in anterior 2/3 tongue
• (GVE) Parasympathetic supply to salivary glands (sublingual and submandibular glands)

• Outside the skull
• Posterior auricular nerve (SVE)
• Motor to some muscles around the ear.
• Motor branches to neck muscles (SVE)
• digastric and stylohyoid muscles
• Within the parotid gland, the nerve splits into five more branches responsible for innervating muscles of facial expression: (SVE)
• Temporal branch –  Innervates the frontalis, orbicularis oculi and corrugator supercilii
• Zygomatic branch –  Innervates the zygomatic muscles (smiling), orbicularis oculi
• Buccal branch – Innervates the orbicularis oris, buccinator and zygomaticus muscles
• Marginal Mandibular branch– Innervates the mentalis muscle
• Cervical branch – Innervates the platysma

Innervates the orbicularis oris, buccinator and zygomaticus muscles

Innervates the mentalis muscle

Innervates the platysma

• Cochlear nerve
• Innervates cochlea (sense organ in the ear)
• Transmits sound for hearing
• Vestibular nerve
• Innervates the semi-circular canals of the inner ear
• Balance, body position and proprioception

5 main components:

• GVA - General Visceral Afferent
• carries sensory information from the carotid sinus and body
• GSA - General Somatic Afferent
• Carries general sensory information from the tympanic membrane, skin of the external ear, upper pharynx, and the posterior one-third of the tongue (*general sensation).
• SVA - Special Visceral Afferent
• – provides *special sense of taste from the posterior one-third of the tongue
• SVE – Special Visceral Efferent
• - Branchial motor component Innervates the stylopharyngeus muscle (under jaw area)
• GVE - General Visceral Efferent
• – Parasympathetic innervation of parotid gland– salivary glands

• GSA - General somatic afferent
• sensory from pharynx, larynx sensory from auditory areas
• GVA - General visceral afferent
• sensory from organs in the thoracic and abdominal regions, aortic body and arch (heart)
• SVA - Special visceral afferent
• special sensory from root/base of tongue and epiglottis region
• SVE - Special visceral efferent
• motor to muscles of the pharynx and larynx.
• GVE - General visceral efferent
• parasympathetic innervation to glands of mucous membranes of the pharynx, larynx, organs in the neck, thorax (chest – heart), and abdomen.

CNXII:  Hypoglossal Nerve