1broca's aphasia
expression impaired, comprehension intact, repetition impaired
2wernicke's aphasia
expression fluent but lacking content, comprehension impaired, repetition impaired
3conduction aphasia
expression intact, comprehension intact, repetition impaired
4global aphasia
expression impaired, comprehension impaired, repetition impaired
5transcortical motor aphasia
expression impaired, comprehension intact, repetition intact
6transcortical sensory aphasia
expression fluent, comprehension impaired, repetition impaired
7stroke definition
a cerebrovascular accident where brain tissue in a region of the brain dies as a result of disrupted blood flow
8stroke types
hemorrhagic (blood vessel rupture due to hbp or aneurysm), ischemic (blood vessel blockage due to embolism or plaque)
9anterior cerebral artery stroke causes:
left: transcortical motor aphasia, right: no aphasia, bilateral mutism
10left middle cerebral artery stroke causes:
anterior: broca's aphasia, transcortical motor aphasia, right arm hemiplegia
posterior: wernicke's aphasia, transcortical sensory aphasia, right arm weakness
entire branch: global aphasia, right hemiplegia
11right middle cerebral artery stroke causes:
middle: no aphasia, left hemiplegia
12posterior cerebral artery stroke causes:
left: alexia, right: no alexia, bilateral: cortical blindness
13transduction of sound
stapes movement on the oval window displaces perilymph in scala vestibuli + endolymph in scala media, which deflects basilar membrane and moves hair cells on organ of Corti, which bends stereocilia, which opens mechano-gated K+ channels causing depolarization which triggers exocytosis and releases glutamate that binds to the neurites of the auditory nerve
14auditory pathway:
hair cells, spiral ganglion, ipsilateral cochlear nuclei, ipsilateral and contralateral superior olive, inferior colliculus, thalamus, auditory cortex
15types of aphasia
broca's, wernicke's, conduction, global, transcortical motor, transcortical sensory,
16region affected in broca's aphasia:
broca's area and frontal fields and underlying matter around it, basal ganglia
17region affected in wernicke's aphasia
wernicke's area and underlying white matter, posterior areas of auditory association cortex
18region affected in conduction aphasia
arcuate fasciculus
19region affected in global aphasia
massive peri-sylvian lesion
20region affected in transcortical motor aphasia
frontal cortex anterior or superior to broca's area
21region affected in transcortical sensory aphasia
temporal cortex posterior or inferior to wernicke's area