L8 Intro to Cranial Nerves - McGrew PDF

Moore’s Clinically Oriented Anatomy Pgs. 1061-1086 Slide - Lecture 3: Spinal Cord and Meninges (2024) - Adam Kolatorowicz, PhD Afferent = Sensory (from periphery to CNS) Sensory (visceral or somatic) = pseudounipolar neurons with cell bodies outside the CNS (in ganglia); less ov...

Moore’s Clinically Oriented Anatomy Pgs. 1061-1086 Slide - Lecture 3: Spinal Cord and Meninges (2024) - Adam Kolatorowicz, PhD Afferent = Sensory (from periphery to CNS) Sensory (visceral or somatic) = pseudounipolar neurons with cell bodies outside the CNS (in ganglia); less overlap between skin innervated by cranial nerves than by spinal nerves (very distinct) Efferent = Motor (from CNS to effector organs) Motor = multipolar neurons in the gray matter of spinal cord or in autonomic ganglia Somatic - soma ‘body” - the regions of the body you can consciously influence Visceral - relating to organs Proprioception comes partially from vestibular apparatus (part of CN VIII) Parasympathetic - “Rest & Digest” (SLUDG - Salivation, Lacrimation, Urination, Defecation, GI Motility) - In H&N Pupillary Function, Salivation, Lacrimation; all parasympathetic fibers originate from the cranial nerves Sympathetic - “Fight or Flight” - All the sympatheticfibers originate from the superior cervical ganglia MUST HAVE MOTOR COMPONENT TO BE INVOLVED IN PARASYMPATHETIC FUNCTION (EFFERENT FIBERS) Introduction to the Autonomic Nervous System - PsychDB Numbering from rostral to caudal locations of nuclei within brainstem:Anatomical Terminology – Foundations of Neuroscience Above the pons (4) Cortex (2) - I, II Midbrain (2) - III,IV Pons (4) - V, VI, VII, VIII Medulla (4) - IX, X, XII, XI True olfactory nerves (filia olfactoria) emerge from the olfactory bulbs. After dissolving in mucous, olfactory information is transmitted along the bipolar olfactory nerves where they synapse with mitral cells in the olfactory bulbs. The secondary neurons form the olfactory tract (extensions of the forebrain) which divide into medial / lateral olfactory stria (fiber bands). Lateral - piriform cortex of anterior temporal lobe, medial - anterior commissure to contralateral olfactory structures Facial trauma or meningioma in anterior fossa - extreme trauma can cause rupture of meninges, patient would present with anosmia (no smell), terrible headaches, and possibly clear fluid dripping from their nose; tumor would result in progressive loss of smell Diencephlaon - thalamus, hypothalamus, posterior pituitary, and pineal gland Cell bodies are in the retina (ganglion cells) Most terminate in the lateral geniculate body of the thalamus Unilateral Monocular Blindness - damage to ipsilateral optic nerve Bitemporal Hemianopsia - damage to medial optic chiasm Unilateral Homonymous Hemianopsia - damage to optic tract Edinger-Westphal nucleus (Presynaptic) Ciliary Ganglion (Postsynaptic) Moves gaze inferolaterally and medially rotates (or inferiorly when adducted) - named for troclea (pulley) Only cranial nerve to begin on the dorsal surface of midbrain and passes anteriorly “Standing Room Only” No parasympathetic functions but postsynaptic fibers from CN III, VII, IX use as a “highway” to reach target organ Ciliary Ganglia PT Ganglia Motor - V + 3 = 8 muscles (4 mm of mastication, 2 tensors, a shoulder and a belly) Otic & Submandibular Ganglia SO4, LR6, All the rest 3 Cranial Nerve Palsy – CN III, IV, VI & VII Palsy MM of facial expression (Frontalis, Orbicularis Oculi, Orbicularis Oris, Zygomaticus Minor and Major, Buccinator, Platysma, et cetera) Presynaptic - superior salivatory nucleus; Postsynaptic pterygopalatine and submandibular ganglia Exact causes unknown, often attributed to viral infection such as herpes zoster Bell's Palsy: Causes, Symptoms, Diagnosis, Treatment, Outlook “7 & 8 going on a date – acoustic music – bad date” Vestibular ganglion (Synapse: Vestibular nuclei) Spiral Ganglion (Cochlear nuclei) Begins as a tumor of the neurilemma (Schwann) cells of the the vestibular nerve. Symptoms include progressive hearing loss, dysequilibrium, tinnitus Acoustic neuroma - Symptoms and causes - Mayo Clinic 3, 9, 7, 7 - COPS ○ Medulla (Presynaptic - inferior salivatory nucleus; postsynaptic - otic ganglion) literally “wandering” Medulla [Presynaptic; postsynaptic - intrinsic ganglia of viscera (on or near)] Hypoglossalululul - styloglossus, hyoglossus, genioglossus Hypoglossalululul IMPORTANT Trends: 5, 4, 3 3, 7, 9, 10 (3, 9, 7, 7 - COPS) Exit Buddies Four nerves of the pharyngeal arches https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1445- 5994.2004.00732.x#:~:text=In%20summary%2C%20if%20one%20can,nerves%20ab ove%20the%20pons%20with