Flashcards in Aphasias Deck (18):
What is aphasia?
A disturbance in language (not speech) as a result of brain damage
List 3 categories of causes of aphasias, giving specific examples
Acute onset (stroke, penetrating head injury, surgical resection)
Insidious onset/progressive (dementia, neoplastic change)
Paroxysmal/episodic (focal seizures, migraine)
Describe the lateralisation of language
The left hemisphere is dominant for language in ~95% of right handers and 70% of left handers
What is the role of the right hemisphere in language?
Paralinguistic aspects of speech
Describe the lateralisation of visuospatial function
The right hemisphere is dominant for visuospatial function
What cortical regions does the superior division of the middle cerebral artery supply?
Ventrolateral prefrontal cortex
What cortical regions does the inferior division of the middle cerebral artery supply?
Describe the location and predominant impairments of a Broca's aphasia
Anterior lesion affecting Broca's area
Loss of grammatical (sequential) structure
Fluent jargonistic language output (neologisms and paraphasic errors e.g. boap for boat)
Describe the location and predominant impairments of a Wernicke's aphasia
Posterior lesion affecting Wernicke's area
Impaired selection of content
Non-fluent, highly effortful language output
Right face and arm weakness
Describe the two aspects of the language system
Production (producing appropriate output sequences, putting words together in a meaningful way making appropriate use of grammar and context)
Selection (choosing appropriate content, picking the right word for the object)
Which language structures are supplied by the superior division of the middle cerebral artery?
Broca's area (composed of pars triangularis and pars opercularis)
Which language structures are contained within the temporoparietal association neocortex?
What results from a severing of the arcuate fasciculus?
What are the defining features of a conduction aphasia?
Fluent aphasia, but more meaningful than Wernicke's
Relatively intact auditory comprehension
Poor repetition of words
What are the defining features of a transcortical motor aphasia?
Muteness at most severe
What are the 2 main mechanisms of language recovery?
Contralateral transfer (better recovery)
Under what circumstances does contralateral transfer of language function tend to occur?
Following early hemispherectomy, in neonatal infarction or with major developmental abnormalities