MBBS · Human Anatomy

Cranial nerves

The twelve pairs of cranial nerves connect the brain and brainstem with sensory and motor functions in the head, neck and selected viscera.

Open interactive lesson & self-check ↗

Twelve cranial nerves: function map

Original conceptual SVG · scalable
BRAIN& brainstemI smellII visionIII eye movementIV eye movementV face sensationVI eye abductionVII facial expressionVIII hearing / balanceIX pharynx / tasteX visceral / voiceXI neck musclesXII tongue movementI–XII numbered in order · sensory and motor pathways are simplified

Concept overview only; many cranial nerves have mixed functions and complex nuclei. Use anatomy atlases for detailed course and lesions.

Concept 01

Organize by functional role

I olfaction; II vision; III IV VI eye movement; V facial sensation and mastication; VII facial expression and taste; VIII hearing and balance; IX X swallowing and visceral function; XI neck muscles; XII tongue movement.

Concept 02

Connect nerve to bedside examination

Pupillary light reflex includes II as the afferent limb and III as the efferent limb. Corneal reflex uses V1 sensory input and VII blink output.

Concept 03

Localize a problem

Compare multiple nerve findings with brainstem, skull-base and peripheral distributions; clinical localization requires a complete examination.

Education / safety note: Functional categories overlap: several cranial nerves have both motor and sensory components.

Reference and next reading

Explore the original curriculum and publisher-hosted resources for full-depth reading; this note is an original schematic introduction, not an exhaustive chapter.

Official / publisher source: NMC official CBME Curriculum 2024 and current regulations index ↗Official / publisher source: OpenStax Anatomy and Physiology 2e (read on publisher site) ↗Official / publisher source: PubMed ↗