Anatomy and Physiology: Nervous System - Cranial Nerves

Overview

• This lecture is the last in a series on the nervous system for lecture test five.
• Previous video covered brain structure and function.
• Focus on the 12 pairs of cranial nerves, their functions, and characteristics.

Cranial Nerves

• 12 pairs of cranial nerves in total, with specific functions.
• Differences between spinal nerves (mixed sensory and motor) and cranial nerves (which can be sensory, motor, or mixed).

Detailed Overview of the 12 Cranial Nerves:

1. Olfactory Nerve (Cranial Nerve I)

   • Roman numeral: I
   • Type: Sensory
   • Function: Sense of smell (olfaction); connects nose to brain.
   • Pathway: Nose to temporal lobe.

2. Optic Nerve (Cranial Nerve II)

   • Roman numeral: II
   • Type: Sensory
   • Function: Vision
   • Pathway: From retina through optic nerve to visual cortex.

3. Oculomotor Nerve (Cranial Nerve III)

   • Roman numeral: III
   • Type: Motor
   • Functions: Eye movement, eyelid movement, pupil constriction/dilation.

4. Trochlear Nerve (Cranial Nerve IV)

   • Roman numeral: IV
   • Type: Motor
   • Function: Controls eye movement through the superior oblique muscle (loops through trochlea).

5. Trigeminal Nerve (Cranial Nerve V)

   • Roman numeral: V
   • Type: Mixed
   • Function: Sensory from face (ophthalmic, maxillary, mandibular branches); Motor for mastication.

6. Abducens Nerve (Cranial Nerve VI)

   • Roman numeral: VI
   • Type: Motor
   • Function: Eye movement (lateral rectus muscle).

7. Facial Nerve (Cranial Nerve VII)

   • Roman numeral: VII
   • Type: Mixed
   • Function: Facial expressions; taste from anterior two-thirds of the tongue.

8. Vestibulocochlear Nerve (Cranial Nerve VIII)

   • Roman numeral: VIII
   • Type: Sensory
   • Function: Hearing and equilibrium.
   • Other Names: Auditory nerve, Acoustic nerve.

9. Glossopharyngeal Nerve (Cranial Nerve IX)

   • Roman numeral: IX
   • Type: Mixed
   • Function: Sensory and taste from posterior one-third of the tongue; controls some swallowing muscles and salivary glands.

10. Vagus Nerve (Cranial Nerve X)

    • Roman numeral: X
    • Type: Mixed
    • Function: Controls autonomic functions of the heart, lungs, and digestive tract; sensory for trunk position.

11. Spinal Accessory Nerve (Cranial Nerve XI)

    • Roman numeral: XI
    • Type: Motor
    • Function: Moves throat muscles for swallowing; some neck muscle movements.

12. Hypoglossal Nerve (Cranial Nerve XII)

    • Roman numeral: XII
    • Type: Motor
    • Function: Tongue movement for speech.

Important Points

• There will be quiz questions on the cranial nerves and previous video content on brain structure and function.
• Nervous system lecture series emphasizes cranial nerve functionality and brain anatomy.
• Note on semester extension due to circumstances; students encouraged to reach out if difficulties arise.

Conclusion

• The lecture emphasized the complexity and importance of cranial nerves.
• Encouragement to continue studying and reach out for assistance if needed.
• Reminder of the upcoming quiz covering this material.