The 12 pairs of cranial nerves originate from the brain and pass through openings in the skull. They are divided into sensory, motor, and mixed nerves. The document then proceeds to describe the names, components, origins, openings through the skull, and functions of each of the 12 cranial nerves. It concludes by outlining some common dysfunctions that can occur with damage to specific cranial nerves, such as anosmia from damage to the olfactory nerve or Bell's palsy from damage to the facial nerve.

1. CRANIAL
NERVES

2.  The 12 pairs of cranial nerves arise from the
brain inside the cranial cavity and pass through
various foramina in the bones of the cranium.
 Cranial nerves divides into three functions:
 Sensory nerves
 Motor nerves
 Mixed nerves

4. SENSORY NERVES: Olfactory
nerve,Optic nerve,vestibulo cochlear
nerve
MOTOR NERVES: Oculomotor
nerve,Trochlear nerve,Abducens
nerve,accessory nerve,Hypoglossal
nerve
MIXED NERVES: Trigeminal nerve,Facial
nerve,Glossopharyngeal nerve,Vagus
nerve

5. OLFACTORY
NERVE(I)

6. OLFACTORY(I):
oComponent: sensory
oFunction: smell
oOrigin: olfactory receptor nerve cell
oOpening to the skull: Openings in
cribriform plate of ethmoid bone on
each side of the nose.

8. OPTIC NERVE(II)

9. OPTIC NERVE(II):
oComponent:sensory
oFunction:vision
oorigin:from the back of the eyeball.
oOpening to the skull: to the optic canal

11. OCULOMOTOR
NERVE(III)

12. OCULOMOTOR NERVE(III):
Oculo=eye ; motor= a mover
ocomponent: motor
oOrigin : from the anterior part of the midbrain.
oOpening to the skull: pass through the supra
orbital fissure into the orbit.
oFunctions :
•Raises upper eyelid
•Movement of eyeball
•Pupil constriction
•Eye accommodation

14. TROCLEAR NERVE

15. TROCLEAR NERVE(IV):
trochle= a pulley
Trochlear is the smallest of all the 12
cranial nerves.
ocomponent:motor
oOrigin : posterior surface of mid brain.
oOpening to skull:superior orbital
fissure
oFunction:involves in movement of
eyeball downward and laterally.

17. Ophthalmic nerve
Maxillary nerve
Mandibular nerve
TRIGEMINAL NERVE(V)

19. OPHTHALMIC NERVE:
oComponent: sensory
oOrigin: anterior aspect of pons
oOpening to the skull: superior orbital
fissure
oFunctions:
•Cornea
•Skin of fore head
•Eyelids and nose
•Mucous membranes of paranasal sinuses
and nasal cavity
•Scalp

20. Opthalmic nerve again has three branches:
Frontal nerve:supplies to
upperlid,frontalis,scalp,conjunctiva,forehead
Lacrimal nerve: supplies to lacrimal gland,
conjunctiva,and upperlid
Nasociliary nerve: supplies to cornea
,iris,ciliary body, upperlids,nose
bridge,conjunctiva.

22. MAXILLARY NERVE :
oComponent: sensory
oOrigin: anterior aspect of pons
oOpening to skull: foramen ovale
oFunction:
Skin of the face over maxilla
Teeth of upperjaw
Mucous membrane of the nose , the maxillary
sinus and palate

23. MANDIBULAR NERVE:
oComponent: motor & sensory
oorigin: anterior aspect of pons
oOpening to the skull: foramen rotundum
o Function:
Muscles of mastication
Mylohoid
Anterior belly of digastric
Tensor veli palatine
Tensor tympani
Skin of cheek
Teeth of lower jaw

24. ABDUCENT NERVE

25. ABDUCENT NERVE(VI):
Ab= away; ducens= to lead
oComponent: motor
oOrigin: medulla oblongata
oOpening to the skull: superior orbital fissure
oFunction: lateral rectus muscle turns eyeball
laterally

27. FACIAL NERVE

28. FACIAL NERVE(VII):
oComponent: mixed
oOrigin: medulla oblongata
oOpening to the skull: internal acoustic
meatus ,facial canal,stylomastoid foramen
oFunction:
Motor
•Muscles of the face and scalp
•Stapedius muscle
•Posterior belly of digastric
•Stylohyoid muscles

29. oFunction:
Sensory
•Taste from anterior 2/3 of tounge, from the
floor of the mouth and palate
oFunction:
Secretomotor
•Submandibular and sublingual salivary glands
•Lacrimal gland
•Glands of nose and palate

31. VESTIBULOCOCHLEAR
NERVE

32. VESTIBULOCOCHLEAR NERVE(VIII):
vestibulo= small cavity; cochlear=spiral, snail-like
oComponent: sensory
oOrigin: medulla oblongata
oOpening to the skull: internal acoustic meatus
oFunction:
It has two branches
1. Vestibular branch- carries impulses for
equilibrium
2. Cochlear branch- carries impulse for hearing

34. GLOSSOPHARYNGEAL
NERVE

35. GLOSSOPHARYNGEAL NERVE(IX):
oComponent: mixed
oOrigin: medulla oblongata
oOpening to the skull: jugular foramen
oFunction:
motor
•Stylopharyngeus muscle- assists swallowing
sensory
•General sensation and taste from post. ½ of the
tounge and pharynx
•Carotis sinus and carotid body
• secretomotor
•Parotid gland

37. VAGUS NERVE

38. VAGUS NERVE(x):
oComponent: motor
oOrigin: medulla oblongata
oOpening to the skull: jugular foramen
oFunction:
•Heart and great thoracic blood vessels
•Larynx, trachea, bronchi and lungs
•Alimentary tract from pharynx to spenic
flexure of colon
•Liver , kidney , pancreas

40. ACCESSORY
NERVE

41. ACCESSORY NERVE(XI):
oComponent: motor
oOrigin: medulla oblongata
oOpening to the skull: jugular foramen
oFunction:
It is divided into two branches
•Cranial accessory nerve:
-Muscles of soft palate
- muscles of pharynx
-Muscles of larynx
• spinal accessory nerve:
- Sternocleidomastoid and trapezious muscle

43. HYPOGLOSSAL
NERVE

44. HYPOGLOSSAL NERVE(XII):
hypo= below; glossal = tongue
oComponent: motor
oOrigin: medulla oblongata
oOpening to the skull: hypoglossal canal
oFunction:
•Muscles of tongue

46. DYSFUNCTIONS
OF NERVES

47. Dysfunction of olfactory nerve:
ANOSMIA-
loss of sense of smell
Causes: due to head injuries, lesions along the
olfactory pathway or in brain ,smoking or
cocain use.

48. DYSFUNCTION OF OPTIC NERVE:
ANOPIA-
Blindness due to a defect in or loss of one or both eyes is
called anopia.

49. DYSFUNCTION OF OCULOMOTOR
NERVE:
STRABISMUS
PTOSIS

50. DYSFUNCTION OF TROCHLEAR NERVE
AND ABDUCENS NERVE:
DIPLOPIA

51. DYSFUNCTION OF FACIAL NERVE:
BELLS ‘ PALSY

52. DYSFUNCTION OF
VESTIBULOCOCHLEAR NERVE:
VERTIGO- a feeling that one ‘s own body or the
environment rotating
Ataxia- muscular incordination
Nystagmus- involuntary rapid movement of
eyeball
Tinnitus- ringing in the ears or deafness

53. Dysfunction of glossopharyngeal nerve:

54. Dysfunction of vagus nerve: gastroparesis

55. DYSFUNCTION OF ACCESSORY NERVE:
Impaired movements of neck, shoulder

56. DYSFUNCTION OF HYPOGLOSSAL
NERVE:
Dysarthria-difficult of speaking
Dysphagia- difficult of swallowing

57. REFERENCE:
[1]Tortora GJ, Derrickson B. Anatomy & Physiology.
Wiley India Pvt Limited; 2014.