Cranial nerves introduction

The 12 cranial nerves...

Listed from most anterior to most posterior  Olfactory nerve                                              Optic nerve Oculomotor nerve  Trochlear nerve Trigeminal nerve Abducent nerve Facial nerve  Vestibulocochlear nerve Glossopharyngeal nerve Vagus nerve  Accessory nerve Hypoglossal nerve 

Sensory or motor?

i) Sensory (afferent) modalities General somatic sensory (GSS) - general sensation from skin General visceral sensory (GVS) - general sensation from viscera Special somatic sensory (SSS) - senses derived from ectoderm (sight, sound & balance) Special visceral sensory (SVS)- senses derived from endoderm (taste) 

ii) Motor (efferent) modalities General somatic motor (GSM) - Skeletal muscles General visceral motor (GVM) - Smooth muscles of gut & autonomic motor  Special visceral motor (SVM) - Muscles derived from pharyngeal arches 

Origin stories & exit points

i) Origins  Cerebrum = Olfactory & Optic nerves Brainstem: Midbrain = Trochlear nerve - posterior side  Midbrain - pontine junction = Oculomotor nerve  Pons = Trigeminal nerve Pontine - medulla junction = Abducens, Facial & Vestibulocochlear nerves Medulla Oblongata : Glossopharyngeal, Vagus & Accessory nerves = Posterior to the olive Hypoglossal = Anterior to the olive

ii) Exits  Listed anterior to posterior  Cribiform plate = Olfactory nerve Optic canal = Optic nerve Superior orbital fissure = Oculomotor, Trochlear, Opthalmic division of Trigeminal Foramen rotundum = Maxillary division of Trigeminal  Foramen ovale = Mandibular division of Trigeminal  Internal acoustic meatus = Facial & Vestibulocochlear nerves  Jugular foramen = Glossopharyngeal, Vagus & Acessory nerves  Hypoglossal canal = Hypoglossal nerve  ** Cranial nerves with the number 2 in them (Optic & Hypoglossal) exit through a canal of the same name + only cranial nerves that pass through canals! **

Brainstem nuclei