Cranial nerves (I–XII)

Looks like

Twelve pairs of nerves leaving the brain directly through holes in the skull base.

What it does

Carry smell, sight, eye movement, face sensation and expression, hearing, balance, taste, swallowing and voice.

Keeping it well

Nothing special day to day. Sudden double vision, a drooping face or lost hearing on one side needs same-day assessment.

Its parts

• I — Olfactory nerve
• II — Optic nerve
• III — Oculomotor nerve
• IV — Trochlear nerve
• V — Trigeminal nerve
• VI — Abducens nerve
• VII — Facial nerve
• VIII — Vestibulocochlear nerve
• IX — Glossopharyngeal nerve
• X — Vagus nerve
• XI — Accessory nerve
• XII — Hypoglossal nerve

Related conditions

• Amyloidosis (AL and ATTR)
• Bell's palsy
• Botulism
• Chickenpox (varicella)
• Chronic neuropathic pain
• Chronic pain syndrome
• Cluster headache
• Cold sores (herpes simplex)
• Drooping eyelid (ptosis)
• Fibromyalgia
• Glaucoma
• Guillain-Barré syndrome
• Hearing loss & presbycusis
• Idiopathic intracranial hypertension
• Loss of smell (anosmia)
• Lyme disease
• Migraine
• Multiple sclerosis
• Myasthenia gravis
• Neurofibromatosis type 1
• Neuromyelitis optica spectrum disorder
• Peripheral neuropathy
• Pituitary adenoma
• Rabies
• Restless legs syndrome
• Shingles (herpes zoster)
• Tetanus
• Trigeminal neuralgia
• Vestibular schwannoma (acoustic neuroma)
• Vitamin B1, C and other deficiencies