Cranial nerves and their functions

Cranial Nerves and Their Functions

Here is a consolidated list of the cranial nerves along with their main functions:

  1. Olfactory Nerve : Responsible for the sense of smell.
  2. Optic Nerve : Involved in the pupillary light reflex.
  3. Oculomotor Nerve : Controls eye muscles; associated with LR6 (Lateral Rectus controlled by Abducens), SO4 (Superior Oblique controlled by Trochlear), and other eye movements.
  4. Trochlear Nerve : Specifically controls the Superior Oblique muscle (SO4).
  5. Trigeminal Nerve : Afferent limb of the corneal reflex; causes jaw deviation towards the same side as the lesion.
  6. Abducens Nerve : Controls the Lateral Rectus muscle (LR6).
  7. Facial Nerve :
    • LMN (Lower Motor Neuron) lesions cause facial paralysis in both upper and lower halves.
    • UMN (Upper Motor Neuron) lesions result in lower facial paralysis only.
    • Provides taste sensation from the anterior two-thirds of the tongue.
  8. Vestibulocochlear Nerve : Responsible for hearing and balance.
  9. Glossopharyngeal Nerve : Facilitates taste from the posterior one-third of the tongue and is involved in the gag reflex.
  10. Vagus Nerve :
    • Motor innervation to the soft palate, pharynx, and larynx.
    • Sensory information from viscera; a weak cough can lead to uvula deviation towards the opposite side of the lesion.
  11. Accessory Nerve : Innervates the trapezius and sternocleidomastoid muscles; can result in a dropped scapula.
  12. Hypoglossal Nerve : Controls tongue movement, causing deviation towards the same side of the lesion.

This summary outlines the key functions associated with each cranial nerve.