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This Concept Map, created with IHMC CmapTools, has information related to: Week 2, Case 1: Frontal Cortex & Language Function Microbiology NONE, Case 3: Taste and Facial nerve Bell's Palsy Microbiology HSV-1: After residing within the cranial nerve ganglia, can reactivate and result in facial nerve inflammation which causes compression of CN VII. Also causes loss of taste and salivation on the affected side of the face., Case 3: Taste and Facial nerve Bell's Palsy Related Disorders Other causes: trauma, severe otitis media, Lyme disease, tumor, sarcoidosis, and HIV. Facial nerve tumors Lyme disease Ramsay Hunt syndrome (herpes zoster oticus), Case 2: Posterior Circulation Sign/symptoms Change in behavior Confusion Paranoia Falling (syncope?) Diplopia Coma Homonymous left visual field deficit Hypertension (BP 189/100) Ptosis-Right side R pupil deviation down and out MRI: Infarct of midbrain, thalmi, and L visual cortex, Case 1: Frontal Cortex & Language Function Related Disorders * Broca’s aphasia-a condition in which a patient is unable to produce speech although comprehension is intact * Wernike’s aphasia-Often described as word salad, comprehension is impaired, but speech is intact, the patient would be able to repeat a list of words but unlikely to correctly answer a question * Conduction aphasia – lesion to arcuate fasciculus; presents with impaired repetition. * Global aphasia – Damage to the Broca’s area, Wernicke’s area, and the arcuate fasciculus. Presents with impaired speech, naming, comprehension, repetition, reading, and writing. * Transcortical motor aphasia – associated with watershed lesions. Presents with nonfluent speech; repetition intact. * Transcortical sensory aphasia – Associated with watershed lesions. Presents with fluent speech and impaired comprehension; repetition intact., Case 2: Posterior Circulation Biochemistry *Ischemic stroke initiates a cascade of events: including ATP depletion, ionic dysregulation, increased release of glutamate and the excess production of free radicals, as well as edema and inflammation →all these events eventually contribute to cell death. * Gliosis: marker of CNS injury, +GFAP, Case 1: Frontal Cortex & Language Function Physiology Aphasia types: Broca's aphasia: impairment of the frontal lobe; inferior frontal gyrus leading to Nonfluent speech; stuttering, decreased grammar. Inability to speak language despite understanding. impaired repetition. Wernicke's aphasia: impairment of temporal lobe; left superior temporal area leading to “word salad”; fluent speech w/ paraphrastic errors. Being unaware of the condition. Impaired comprehension.Impaired repetition. Conduction aphasia: impairment of arcuate fasciculus only (left parietal lobe). Leading to impaired repetition. Transcortical motor aphasia: impairment in watershed regions leading to nonfluent speech with good comprehension and intact repetition. Transcortical sensory aphasia: impairment in watershed regions leading to impaired comprehension with intact repetition and fluent speech. Transcortical mixed aphasia: impairment in watershed regions leading to impaired comprehension, non fluent speech but intact repetition. Global aphasia: impairment of brocas (brodmann area 44, 45) , wernicke's (brodmann area 22) and arcuate fasciculus leading to impaired repetition, non fluent speech, and impaired comprehension. Left frontal ischemic infarction (stroke): possibly due to thrombotic occlusion of the right middle cerebral artery (weak right arm), Case 2: Posterior Circulation Pharmacology tPA-used to break down clots, e.g., Alteplase Nicotine-Nicotinic receptor agonist, Case 1: Frontal Cortex & Language Function Anatomy *Posterior limb of internal capsule-the site for pure motor strokes *Perisylvian Language Areas: around sylvian sulcus in the dominant hemisphere (Pt is right handed,so the lesion is on left hemisphere), *responsible for the ability to repeat language, impaired in this pt (Perisylvian aphasias), Case 2: Posterior Circulation Related Disorders * “Locked in syndrome” - basilar artery ischemia; damage to bilateral ventral pons causing UMN signs, quadriplegia, bulbar palsy, horizontal gaze palsy, loss of voluntary respiration, while preserving consciousness, language comprehension, vertical eye movement, blinking, and skin sensations. * Ruptured berry aneurys: a common cause of subarachnoid hemorrhage can cause compression of surrounding structures due to lack of room to expand, a medical emergency, Case 2: Posterior Circulation Microbiology None, Case 3: Taste and Facial nerve Bell's Palsy Sign/symptoms History of flu several weeks ago Paralysis of left side face and eyelid PE: left facial droop with a decreased left nasolabial fold, and slightly increased size of the palpebral fissure on the left versus the right When asked to close her eyes, her left eye looks upward, but the lids are not able to completely close Lost taste sensation on left side of tongue, Case 3: Taste and Facial nerve Bell's Palsy Biochemistry Oxidative stress by the production of reactive oxygen species (ROS) has the ability to cause nerve damage ROS → Cell damage → Inflammation → Compression of CN VII Disruption of acetylcholine → muscle weakness and paralysis., Case 2: Posterior Circulation Anatomy & Physiology Oculomotor nerve- impingement of the oculomotor nerve causes a “down and out” gaze characteristic of oculomotor nerve palsy Basilar artery-the basilar artery is part of the circle of Willis provides collateral circulation to watershed areas of the brain Thalamus- The thalamus is responsible for processing sensory and motor information in order to coordinate movement and function, Case 3: Taste and Facial nerve Bell's Palsy Anatomy CN VII (facial nerve) innervates all motor function of the ipsilateral side of face, with exception of the levator palpebrae superioris (controlled by CN III), which cause pt able to open left eye but not able to close). CN VII also contains ipsilateral fibers for taste, sensation of the ear, and some of the autonomic fibers controlling salivation., Case 1: Frontal Cortex & Language Function Sign/symptoms * 66 yrs male, history of smoking. Right hand clumsiness started 2 hours ago and progressively worsened to barely move his RUE. * Communication: -Comprehensive language intact. -Difficulty with expressive language: halting, stuttering speech pattern, unable to express self adequately. Word finding difficulties. -Unable to repeat words/phrases. *Unable to sustain his RUE against gravity and weak grip on the right side. *Coordination intact; Sensation and reflexes are normal., Case 3: Taste and Facial nerve Bell's Palsy Pharmacology Muscarinic antagonist: symptomatic control of drooling Prednisolone: decreases inflammation, increases changes of recovery Valacyclovir-an oral antiviral agent to suppress HSV-1 and VZV symptoms, preferentially given over acyclovir due to better oral bioavailability, Case 1: Frontal Cortex & Language Function Pharmacology * tPA-used to break down clots, e.g., Alteplase * Nicotine-Nicotinic receptor agonist * Varenicline-Should be recommended for smoking cessation in order to reduce risk, partial nicotinic receptor agonist, Case 3: Taste and Facial nerve Bell's Palsy Physiology Acute hemifacial palsy LMN dysfunction → affects CN VII → affects motor function of the entire ipsilateral side of the face; Taste on the ipsilateral side of the tongue (compromise of chorda tympani fibers)., Case 1: Frontal Cortex & Language Function Biochemistry * Ischemic stroke initiates a cascade of events: including ATP depletion, ionic dysregulation, increased release of glutamate and the excess production of free radicals, as well as edema and inflammation →all these events eventually contribute to cell death. * Gliosis: marker of CNS injury, +GFAP