Kranialnerv

Kranialnerv, or cranial nerves, are twelve pairs of nerves that originate directly from the brain and brainstem. They are part of the peripheral nervous system and pass through specific skull openings to reach the head and neck. Each nerve carries sensory, motor, or parasympathetic fibers, and they contribute to sensation, movement, and autonomic control in the head and neck region.

The twelve nerves are named and numbered I through XII as follows: I – olfactory (sensory, smell; cribriform plate); II – optic (sensory, vision; optic canal); III – oculomotor (motor to most extraocular muscles; parasympathetic to pupil and lens; superior orbital fissure); IV – trochlear (motor to the superior oblique; superior orbital fissure); V – trigeminal (mixed; three divisions V1–V3; V1 via superior orbital fissure, V2 via foramen rotundum, V3 via foramen ovale); VI – abducens (motor to lateral rectus; superior orbital fissure); VII – facial (mixed; motor to facial muscles; sensory from anterior tongue; parasympathetic to lacrimal and salivary glands; exits via internal acoustic meatus and stylomastoid foramen); VIII – vestibulocochlear (sensory; hearing and balance; internal acoustic meatus); IX – glossopharyngeal (mixed; sensory from posterior tongue and pharynx; taste; parasympathetic to parotid; jugular foramen); X – vagus (mixed; parasympathetic to thorax and abdomen; sensory and motor to pharynx and larynx; jugular foramen); XI – accessory (motor to sternocleidomastoid and trapezius; cranial and spinal roots; jugular foramen); XII – hypoglossal (motor to tongue; hypoglossal canal).