* Compare and Contrast cranial nerves to spinal nerves * Know which cranial nerves are central and which are peripheral * Know the 4 functions of all cranial nerves together * Draw, interpret, and analyze the corticobrainstem tracts * Explain the process of olfaction (receptors, CN I, cortical areas) * Explain taste (receptors, CN VII & IX, solitary n.) * Explain vision (visual field, anatomy & receptors, CN II, visual pathway) * Explain coordination of eye movements (III, IV, VI efferents) * Explain hearing (anatomy & receptors, CN VIII, auditory pathway) * Explain sensory and motor control of face (CN V & VII) * Explain swallowing & speaking (CN V, VII, IX, X efferents) * Explain head control (CN XII efferents) * Explain parasympathetic control of viscera (CN X) * Describe or draw the auditory, visual, and pupillary pathways Special Senses Motor (and somatosensory) Autonomic

Somatosensory Somatomotor Ganglia for afferents outside of CNS Reflexes Sympathetic components Special senses Vary in components (S, M, B) From specialized nuclei in BS Parasympathetic component All have both (B) From gray laminae in SC Cranial NervesSpinal Nerves

* What are cranial nerves? * 4 functions * Motor innervation to muscles of face, eyes, lips, tongue, jaw, and throat * Somatosensory information from face and jaw (touch, vibration, proprioception, pain, etc) * Special senses – vision, hearing, taste, smell, vestibular * Parasympathetic regulation

* Draw the corticobrainstem tracts!! * Refer to this drawing during the rest of the cranial nerves lectures! * Corticobrainstem = corticonuclear = corticobulbar

* Key Structures: * Chemoreceptors * Cranial Nerve I (Olfactory bulb and tract) * Olfactory Cortex * Key Points: * * Dysfunctions called –osmia (ex: anosmia)

* Key Structures: * Chemoreceptors * CN VII & IX (facial & glossopharyngeal) * Solitary Nucleus * VPM, Gustatory Cortex * Key Points: *

* Peripheral vision is only one eye * Blind spot is location of optic nerve in retina * Image is flipped – peripheral vision is located in medial retina * Test your peripheral vision! * Find the edge of vision on your R, first with your R eye, then only with your left. * Find your blind spot! * Close your L eye. Find your R blind spot with a finger.

* Photoreceptors * Located in the retina * Rods – black and white * Cones – 3 pigmented types to detect colors * Cornea  Lens  Retina  Optic n. * Fovea: * * Refraction of light

* Visual * Carries information from retina * Goes to LGB * Then to hypothalamus, midbrain, primary visual cortex * Pupillary * Using visual information in midbrain… * Goes to EW, through oculomotor nerve to constrictor muscles

* CN III, IV, VI * Nuclei in midbrain & pons * Medial Longitudinal Fasciculus * * 4 Rectus muscles, 2 Oblique muscles, 1 eyelid muscle * Movements are normally coordinated

* Sound wave  tympanic membrane  3 ear bones (malleus, incus, stapes)  cochlea  hair cells (mechanoreceptors)  spiral ganglia  cochlear nerve *

* CN VII (facial) * 2 halves of facial nucleus * Upper * Lower * CN V * muscles of mastication

* CN V (trigeminal) * Ophthalmic (V1) S * Maxillary (V2) S * Mandibular (V3) B * Trigeminal nuclei * Mesencephalic * Sensory, Motor * Spinal

* Salivation  CN IX, parotid gland * Somatosensation of posterior tongue & throat * CN IX  Solitary n. * Swallowing * Nucleus Ambiguus, Solitary, Dorsal Motor of X  combination of CNs IX, X, XII

* Motor control of larynx & soft palate * Corticonuclear tract  Nucleus Ambiguus  CN X * Motor control of tongue * Corticonuclear tract  Hypoglossal nucleus  CN XII * Motor control of jaws * Corticonuclear tract  Trigeminal motor nucleus  CN V * Motor control of lips * Corticonuclear tract  Facial nucleus  CN VII

1. Smell: use smelling salts or other substances to test sense of smell (A-1) 2. Pupillary reflex: direct & consensual responses (A-2, E-3) 3. Eye coordination: test for eye position & nystagmus (E-3,4,6) 5. Sensation of face: Touch, pain, temp (A-5) 7. Blink reflex: Test blinking (A-5, E-7) Face muscles: Check facial expressions (E-7) 8. Test balance & hearing 9. Gag reflex: (A-9, E-10) 11. MMT trapezius & SCM (E-11) 12. Tongue: check for atrophy (E-12) Pages LE