Language Flashcards
Differentiate speech from language
Speech: phonation and articulation of words
Language: multimodal or symbolic communication
Define aphasia
Disorder of previously acquired language ability from a language center lesion in the dominant hemisphere
Aphasic patients may speak, but have trouble communicating
Where are the cortical language centers located?
Located in the lateral sulcus in the dominant hemisphere
Left hemisphere in 99% of right handed people
Right hemisphere in 50% of left handed people
Language is disrupted by infarction of what blood supply?
MCA
Differentiate the roles of Wernicke’s vs broca’s area
Wernicke’s: language comprehension, via listening, reading, other modes
Broca’s: language expression or execution, by speaking, writing, other modes
What can cause aphasia?
ischemic infarction (occlusion of dominant MCA or its branches) Hemorrhage, trauma, tumor or dementia
Define “fluency” of language
ease, facility and quantity of speech, regardless of content or meaning
Define paraphasia
Word or syllable substitutions
What is a clinical feature common to all perisylvian aphasias (Broca’s, Wernicke’s, Conduction and global aphasia)?
Imperfect repetition
What lesions cause broca’s aphasia?
posterior, inferior frontal lobe
Describe the speech of someone with broca’s aphasia
Laborious, effortful and NON-fluent
How is comprehension affected by Broca’s aphasia?
It is preserved
Describe the effects of Wernicke’s aphasia
Comprehension is impaired. Speech is preserved –> fluent, but nonsense
What is conductive aphasia?
A lesion in the arcuate fasciculus (tract between Broca’s and Wernicke’s) –> fairly fluent with some paraphasic errors
Comprehension is “intermediate”- imperfect comprehension
What causes global aphasia?
Lesions in Broca’s, Wernicke’s and the arcuate fasciculus
–> severe, nonfluent (mute) speech and poor comprehension
