cranial nerves Names of cranial nerves n n

cranial nerves

Names of cranial nerves n n n Ⅰ Olfactory nerve Ⅱ Optic nerve Ⅲ Oculomotor nerve Ⅳ Trochlear nerve Ⅴ Trigeminal nerve Ⅵ Abducent nerve Ⅶ Facial nerve Ⅷ Vestibulocochlear nerve Ⅸ Glossopharyngeal nerve Ⅹ Vagus nerve Ⅺ Accessory nerve Ⅻ Hypoglossal nerve

Functional components n n n n General somatic afferent fibers (GSA): transmit exteroceptive and proprioceptive impulses from head and face to somatic sensory nuclei Special somatic afferent fibers (SSA): transmit sensory impulses from special sense organs of vision, equilibrium and hearing to the brain General visceral afferent fibers (GVA): transmit interoceptive impulses from the viscera to the visceral sensory nuclei Special visceral afferent fibers (SVA): transmit sensory impulses from special sense organs of smell and taste to the brain General somatic efferent fibers (GSE): innervate skeletal muscles of eye and tongue Special visceral efferent fibers (SVE): transmit motor impulses from the brain to skeletal muscles derived from brachial (gill) arches of embryo. These include the muscles of mastication, facial expression and swallowing General visceral efferent fibers (GVE): transmit motor impulses from the general visceral motor nuclei and relayed in parasympathetic ganglions. The postganglionic fibers supply cardiac muscles，smooth muscles and glands

Classification of cranial nerves n Sensory cranial nerves: contain only afferent (sensory) fibers q q q n Motor cranial nerves: contain only efferent (motor) fibers q q q n ⅠOlfactory nerve ⅡOptic nerve Ⅷ Vestibulocochlear nerve Ⅲ Oculomotor nerve Ⅳ Trochlear nerve ⅥAbducent nerve Ⅺ Accessory nerv Ⅻ Hypoglossal nerve Mixed nerves: contain both sensory and motor fibers--q q ⅤTrigeminal nerve, Ⅶ Facial nerve, ⅨGlossopharyngeal nerve ⅩVagus nerve

Sensory cranial nerves N. Location of cell body and axon categories Cranial exit Terminal nuclei Main action Ⅰ Olfactory cells (SVA) Cribrifom Olfactory foramina bulb Smell Ⅱ Ganglion cells (SSA) Optic canal Lateral geniculate body Vision Ⅷ Vestibular ganglion(SSA) Internal acoustic meatus Vestibular nuclei Equilibri um Cochlear nuclei Hearing Cochlear ganglion (SSA)

Motor cranial nerves N. Nucleus of origin and axon categories Cranial exit Main action Ⅲ Nucleus of oculomotor (GSE) Superior orbital fissure Motor to superior, inferior and medial recti; inferior oblique; levator palpebrae superioris Accessory nucleus of oculomotor (GVE) Parasympathetic to sphincter pupillea and ciliary muscles Ⅳ Nucleus of trochlear nerve (GSE) Superior orbital fissure Motor to superior oblique Ⅵ Nucleus of abducent nerve (GSE) Superior orbital fissure Motor to lateral rectus Ⅺ Nucleus of accessory nerve (SVE) Jugular foramen Motor to sternocleidomastoid and trapezius Ⅻ Nucleus of hypoglossal Hypoglossal canal nerve( GSE) Motor to muscles of tongue except palatoglossus

General somatic efferent nuclei n Nucleus of oculomotor n. n Nucleus of trochlear n. n Nucleus of abducent n. n Nucleus of hypoglossal n.

Special visceral motor nuclei n Motor nucleus of trigeminal n. n Nucleus of facial n. n Nucleus ambiguous n Accessory nucleus

Special visceral efferent nuclei Nucleus Site Cranial n. Function Motor nucleus of trigeminal n. Pons Ⅴ Masticatory muscles, tensor palati & t. tympani Nucleus of facial n. Pons Ⅶ Facial m. , platysma, posterior belly of digastric, stylohyoid, stapedius Nucleus ambiguus Medulla Ⅸ, Ⅹ. Ⅺ Skeletal m. of pharynx, larynx and upper part of esophagus Accessory nucleus MedullaⅪ cervical cord Sternocleidomastoid, trapezius

General visceral motor nuclei n n Accessory oculomotor nucleus Superior salivatory nucleus Inferior salivertory nucleus Dorsal nucleus of vagus n.

General visceral efferent nuclei Nucleus Site Cranial nerve Function Accessory oculomotor nucleus Midbrain Ⅲ Sphincter pupillae and ciliary m. Superior salivatory nucleus Pons Ⅶ Submandibular, sublingual and lacrimal glands Inferior salivertory nucleus Medulla Ⅸ Parotid gland Dorsal nucleus of vagus n. medulla Ⅹ Many cervical, thoracic and abdominal viscera

Visceral sensory nuclei n Nucleus of solitary tract ( general and special )

Visceral sensory nuclei ( general and special ) Nucleus Site Cranial n. Function Nucleus of solitary tract Medulla Ⅶ, Ⅸ, Ⅹ Taste and visceral sensation

General somatic afferent nuclei n Mesencephalic nucleus of trigeminal n. n Main sensory nucleus of trigeminal n. n Spinal nucleus of trigeminal n.

General somatic sensory nuclei Nucleus Site Cranial n. Function Mesencephalic nucleus of trigeminal n. Main sensory nucleus of trigeminal n. Spinal nucleus of trigeminal n. Midbrain Ⅴ Proprioception of head Pons Ⅴ Tactile sensation of face Medulla upto 2 nd cx. seg. Ⅴ Pain and temperature sense of face

Special somatic afferent nuclei n n Cochlear nuclei 2 - Dorsal - Ventral Vestibular nuclei 4 - Superior - Inferior - Medial - Lateral

Special somatic afferent nuclei Nucleus Site Cranial n. Function Cochlear nuclei Pons and medulla Ⅷ Sense of hearing Vestibular nuclei Pons and medulla Ⅷ Sense of equilibrium

Non-cranial nerve nuclei Nucleus Site Gracile nucleus Medulla (underneath gracile tubercle) Cuneate nucleus Medulla (underneath cuneate tubercle) Superior olivery nucleus Pontine nucleus pons Nucleus of inferior colliculus Midbrain Gray matter layers of superior colliculus Midbrain Red nucleus Midbrain Substantia nigra Midbrain Pretectal area Midbrain